taxonID	type	description	language	source
623087C7FF9AFFC9FC217E98FAF9FE98.taxon	description	Characters discussed below pertaining to the question of the monophyly of Chalceus were derived from a cladistic analysis carried out by Zanata (2000) that focused primarily on the systematics of the characid genus Brycon. The analysis was based on 144 morphological characters and 58 characiform taxa and included one Chalceus species (C. macrolepidotus). In that analysis Chalceus is hypothesized as more closely related to African characids and representatives of the Neotropical families Hemiodontidae and Crenuchidae, followed by a clade formed by several representatives of the Neotropical Characidae. The most basal taxa included in that analysis was Xenocharax, proposed as the sister-group of all other characiforms (Fink & Fink, 1981: 306). Characters that supported the monophyletic condition of Chalceus in that analysis were, in the present study, checked in all recognized Chalceus species. Some of the characters proposed by Zanata (2000) as derived for Chalceus species are also present in groups previously hypothesized as being closely related to Chalceus (e. g. Brycon and the African characids (= alestids )) and their eventual utility as synapomorphies for Chalceus depends on a more detailed phylogenetic analysis focused on the relationships of these taxa. We chose to include those characters in the discussion below since they constitute additional distinguishing characters for Chalceus. Supramaxilla (Fig. 1)	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9AFFC9FC217E98FAF9FE98.taxon	description	Series of premaxillary teeth (Fig. 2)	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9AFFC9FC217E98FAF9FE98.taxon	description	The premaxillary dentition in Brycon and Chilobrycon is characterized by an outer series with many cuspidate teeth and an inner series of two large teeth. One or two additional series of teeth are situated between the outer and inner series anteriorly and become aligned posteriorly with the inner series (e. g. see illustrations in Howes, 1982). In Triportheus there is variation in the arrangement of teeth on the premaxilla with two or three series present, in a pattern more similar to that of Brycon. The arrangement of premaxillary teeth in Chalceus is thus a unique pattern among characiforms and is hypothesized to be synapomorphic. Internal series of dentary teeth All Chalceus species possess an internal series of dentary teeth formed by a large symphyseal conical tooth (sometimes tricuspid in large specimens) followed by a gap and a series of smaller conical teeth situated along the dorsal margin of the replacement tooth trenches. The size of the gap varies among Chalceus species and is almost absent in C. macrolepidotus in which the series of small conical teeth is almost continuous with the symphyseal tooth. Internal series of dentary teeth similar to those of Chalceus occur in Brycon and Chilobrycon deuterodon (Zanata, 2000). According to this study, the phylogenetic relationships of Chalceus apparently do not lie with either of those genera and the arrangement of the internal dentary teeth of Chalceus is thus hypothesized to be a synapomorphy for the species of the genus, with the condition in Brycon and Chilobrycon representing convergence. Anterolateral process of the mesethmoid (Fig. 3)	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9AFFC9FC217E98FAF9FE98.taxon	description	In all Chalceus spp. the scales situated dorsal to the lateral line are about twice the size of those situated ventral to it. In the majority of characiforms, including genera proposed as closely related to Chalceus (Zanata, 2000), the scales either decrease gradually in size dorsally to ventrally or those below the lateral line are only slightly smaller than those above it. A condition of the scales similar to that of Chalceus occurs only in the African characid Arnoldichthys spilopterus (Paugy, 1990: 232) among Characiforms. As discussed above, determining whether this feature is either synapomorphic for Chalceus with an independent acquisition in Arnoldichthys or homologous between the two genera necessitates resolution of the relationships of the African characids, which has yet to be determined. Size of lateral-line scales The scales along the lateral-line series of all Chalceus species are alternatively large or small in the region from the posterior margin of the opercle to the anterior portion of the caudal peduncle, and then are approximately equal in size. In the majority of characiforms, including genera proposed as closely related to Chalceus (Zanata, 2000), the scales along the lateral-line series are all of similar size or gradually decrease in size posteriorly. Only Arnoldichthys spilopterus has an arrangement of lateral line scales similar to that of Chalceus. Determining whether this feature is either synapomorphic for the species of Chalceus with an independent acquisition in Arnoldichthys, or indicates phylogenetic affinity between the two genera, depends, as already mentioned, on the resolution of the phylogenetic relationships of the African characids and is beyond the scope of this study.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	diagnosis	Diagnosis: Chalceus is phylogenetically diagnosed on the basis of the following synapomorphies (but see comments in previous section): (1) Presence of supramaxilla; (2) Three series of teeth on premaxilla; (3) Internal series of dentary teeth formed by a large symphyseal conical tooth followed by a gap and a series of smaller conical teeth; (4) Reduced anterolateral process of mesethmoid; (5) Scales situated dorsal to lateral line much larger than those ventral to it; (6) Relative size of scales along lateral line other than on caudal peduncle alternatively large and small. In addition, the combination of the following characters is useful to distinguish the species of Chalceus among characiforms: bright silvery body, red fins and short anal fin.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	description	(1 ¢) Presence of dark pigmentation forming humeral spots or stripes ................................................................................ 2 (2) Humeral spot absent or poorly defined, round to vertically elongate and located deep under scales; presence of narrow longitudinal dark stripe from posterodorsal margin of opercle to caudal peduncle; snout relatively acute; median fontanel between frontals and parietals absent ................................................................................................ 4 (2 ¢) Presence of conspicuous humeral spot, round in shape and located superficially beneath scales; lateral surface of body usually with reticulate pattern; snout rounded; median fontanel present between frontals and parietals .................................................................... 3 (3) Humeral spot with notch on its posterodorsal margin; reticulate pattern of body coloration more evident along series of scales posterior to humeral blotch; pelvic and anal fins dark; caudal-fin lobes robust and rounded (Fig. 10) ................................................. C. erythrurus (3 ¢) Humeral spot without notch on its posterodorsal margin; reticulate pattern of body coloration uniformly distributed over lateral and dorsal portions of body; pelvic and anal fins hyaline; caudal-fin lobes elongate and slender (Figs 15, 16) ................................. C. spilogyros (4) Number of branched pelvic-fin rays 7 (Figs 22, 23) .............................................................................. C. guaporensis (4 ¢) Number of branched pelvic-fin rays 8 (Figs 18, 19) ...................................................................................... C. epakros	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	diagnosis	Diagnosis Chalceus macrolepidotus can be readily distinguished from all other Chalceus species by the absence of any distinct spots of pigmentation or stripes (Figs 4 – 6) (except for some sexually mature specimens, see next section: ‘ Comments on the colour pattern of Chalceus species’, henceforth abbreviated to ‘ Comments ... ’). It differs from C. erythrurus and C. spilogyros by the lack of a humeral spot and from C. epakros and C. guaporensis by the lack of a longitudinal band along the body sides located deep under the skin. In life C. macrolepidotus can be distinguished from C. epakros by the lack of red pigmentation on the central portions of scales on the longitudinal series above the lateral line and from C. erythrurus by having the pelvic and anal fins tinged with red or hyaline (vs. yellow; compare photographs in Géry, 1977: 329 and 332). Chalceus macrolepidotus may be further distinguished from C. erythrurus, C. spilogyros and C. guaporensis in having the first small inner dentary row tooth originating very close to the symphyseal tooth and forming a nearly continuous series (vs. having first small tooth of inner dentary row located well behind the fourth or fifth tooth of the outer row with a distinct gap between the symphyseal tooth and first small conical tooth). Chalceus macrolepidotus can be further distinguished from C. epakros and C. guaporensis by the presence of a fontanel between the contralateral frontal and parietal bones in all but the larger specimens (vs. fontanel absent in all specimens of C. epakros and C. guaporensis). Description Morphometric data presented in Table 1. Maximum size 228.0 mm SL. Body robust, relatively elongate, greatest body depth slightly anterior to dorsal-fin origin. Dorsal profile of head distinctly convex anteriorly along snout region, nearly straight to posterodorsally inclined from anterior end of snout to tip of supraoccipital spine. Dorsal profile of head in large specimens (over 200 mm SL) slightly convex and continuous with dorsal body profile. Anterior margin of snout somewhat acute in dorsal view. Interorbital distance wide, proportionally wider relative to SL in large specimens. Dorsal body profile convex from tip of supraoccipital spine to dorsal-fin origin, posteroventrally inclined along dorsal-fin base, straight to relatively convex to adipose fin and concave along dorsal profile of caudal peduncle to origin of procurrent caudal-fin rays. Overall dorsal profile of head and body of juveniles up to 50 mm SL nearly straight to slightly convex. Ventral profile of head distinctly convex in region of lower jaw, resembling a chin. Ventral body profile gently convex from the posterior limit of isthmus to anal-fin origin. Body profile along anal-fin base posterodorsally inclined, slightly concave along ventral margin of caudal peduncle. Head robust in large specimens (over 180 mm SL). Smaller specimens with relatively longer heads and more acute snout. Dorsal surface of head with distinct medial fontanel restricted to small region anterior to epiphyseal bar between contralateral frontals and completely separating parietals. Fontanel wide in small specimens and progressively narrower in larger individuals. Fontanel completely closed in 200 mm SL specimen. Mouth terminal, large, upper jaw slightly longer than lower jaw, tip of premaxillary teeth extending below margin of upper lip giving saw-like appearance to margin of premaxilla even in closed mouth. Maxilla extending approximately to vertical through anterior margin of orbit. Supramaxilla present. Dorsal-fin rays ii, 10 (ii, 10, n = 92). Dorsal-fin origin posterior to vertical through insertion of innermost pelvic-fin rays. First basal dorsal-fin pterygiophore inserting behind neural spine of 14 th vertebra (n = 1). Distal margin of dorsal fin nearly straight to convex. Adipose fin present. Anal-fin rays iii, 9 (iii, 9; iii, 8 in one specimen, n = 87). First basal anal-fin pterygiophore inserting behind haemal spine of 26 th vertebra (n = 1). Distal margin of anal fin straight to emarginate with anterior branched rays approximately 3 times length of ultimate ray. Pectoral-fin rays i, 15 (range 14 – 18, mean 16, n = 88), pointed distally, with unbranched- and first branched rays longest. Tip of pectoral fin not reaching pelvic-fin insertion. Pelvic-fin rays i, 8 (i, 8; i, 7 in 3 specimens, n = 92); fin pointed distally. Caudal fin forked, with lobes slender, especially in specimens up to 120 mm SL, lower fin lobe slightly more developed than upper lobe. Premaxillary teeth in three rows. Outer row 9 (range 7 – 10; 11 in one specimen, mean 8.5, n = 92) tricuspid or pentacuspid in large specimens; smaller specimens with tricuspid or conical teeth, with medial cusp larger. Tooth close to premaxillary symphysis slightly larger than others in series. Remaining teeth of similar size except for slightly smaller one or two lateralmost teeth. Cusps slightly curved with concave portion facing mouth cavity. Inner row 6 (range 6 – 8; 5 in one specimen, 9 in two, mean 6.4, n = 92) with largest, symphyseal tooth usually asymmetric with one cusp on the medial side and two on the lateral side of tooth. Remaining teeth penta- or heptacuspid in large specimens, all teeth tricuspid in small specimens, with second tooth from symphysis larger and teeth gradually diminishing in size laterally. Cusps slightly curved, with concave portion opposite of mouth cavity. Intermediate row 2 (2; 1 in three specimens, n = 91) pentacuspid (rarely tricuspid) teeth more spaced than teeth of other rows and of intermediate size. Cusps straight. Maxillary teeth 12 (range 8 – 13, with single specimens each having 7, 14, 16 and 17 teeth, mean 10.9, n = 90); smaller specimens usually with higher tooth counts. First teeth pentacuspid followed by tricuspid and conical teeth distally. Maxillary dentition not extending along entire margin of ossification in large specimens. Small specimens with maxillary teeth conical and extending along entire margin of ossification. Dentary teeth in two rows. Outer row 8 (range 8 – 13, 14 in one specimen, 16 in 2, mean 10.9, n = 90). Teeth large and pentacuspid anteriorly, sometimes heptacuspid in large specimens or tricuspid in small specimens, gradually diminishing in size and number of cusps posteriorly. Posteriormost teeth conical. Cusps slightly curved with concave portion facing mouth cavity. Inner row consists of large conical symphyseal tooth (tricuspid in few larger specimens) followed by series of approximately 30 minute conical teeth. First tooth origi- nates very close to symphyseal tooth, forming an almost continuous series. Scales cycloid, large overall, approximately twice as large above lateral line as below it. Circuli on exposed portion of scales not concentric with those of anterior portion; circuli on exposed portion of scales straight and extending to posterior margin of scale in small specimens; restricted to upper and lower portion of scale in specimens around 140 mm SL; disorganized and with labyrinthic pattern in specimens around 170 mm SL. Radii originating on centre of scale and radiating anteriorly and posteriorly on scale surface. Lateral line low on body sides, complete, with alternating large and small perforated scales from posterior margin of opercle to vertical through base of last anal-fin ray; scales smaller and of similar size from that point to end of caudal peduncle. Canals in large specimens with 3 – 9 elevated branches, forming ridges on scale surface; ridges more evident on region of caudal peduncle. Number of branches decreases toward caudal peduncle with posterior scales unbranched. Small specimens (less than 140 mm) with branching pattern less developed. Lateral-line scales 38 (range 36 – 40, mean 38, n = 90). Scale rows between dorsalfin origin and lateral line 3; between lateral line and pelvic-fin insertion 2. Scales around caudal peduncle 12. Vertebrae 39 (n = 1). Colour in life. (Description based on photographs in Géry, 1977: 329 and Planquette et al., 1996: 231). Overall coloration of head and body bright silver. No conspicuous humeral spot. Dorsal portion of eye yellow. One specimen (Géry, 1977: 329) with dorsal profiles of head and body darker. Somewhat indistinct longitudinal stripe extending from rear of orbit through opercle to vertical through adipose fin and patch of dark pigmentation present on middle portion of opercle. Caudal fin bright red, adipose yellowish, all other fins hyaline. Other specimen (Planquette et al., 1996: 231) with dorsal portions of head and body darker. Margins of scales on dorsal portions of body with light concentration of chromatophores, forming fine reticulate pattern. All fins (except pectoral) bright red, more so on their proximal portions. Colour in alcohol. All available specimens lacking guanine on body except for few that retain silvery pigmentation on infraorbital and opercular regions. Ground coloration of head and body in specimens ≥ 60 mm SL yellowish to tan (Figs 4, 5), becoming darker dorsal of horizontal line through dorsal margin of orbit. No longitudinal body stripe or humeral blotch. Dark chromatophores scattered over infraorbitals and opercular region. Scales on body with chromatophores slightly more concentrated along posterior margin, forming fine reticulate pattern more evident in recently collected specimens (although less evident in large specimens). All fins hyaline. Some specimens with dark tips on dorsal- and caudal-fin rays. Ground coloration of specimens £ 60 mm SL (Fig. 6) pale yellowish, somewhat darker dorsally, but difference between dorsal and ventral regions of body less pronounced than in larger specimens. Reticulate pattern of scales more conspicuous than in larger specimens. Pectoral and pelvic fins hyaline. Dorsal and adipose fins dusky. Lower and ventralmost rays of the upper caudal – fin lobes and anal fin dark. Some specimens (MZUSP 58962 (1 of 2); MZUSP 43291; and ANSP 161220) with a dark and wide longitudinal band along the body sides (see ‘ Comments ... ’). Distribution Rio Negro and its tributaries in Amazon basin, middle and upper Río Orinoco basin, Essequibo River drainage in Guyana, Corantijn River drainage in Suriname and perhaps Río Baures, a tributary of Rio Guaporé, along Brazilian-Bolivian border (12 ∞ 32 ¢ S; 64 ∞ 19 ¢ W) (for latter locality see ‘ Remarks’) (Fig. 9). Ecology Puyo (1943: 130) and Planquette et al. (1996: 230) report Chalceus macrolepidotus from well oxygenated waters in regions of rapids; the latter authors mention that the species is uncommon in the lower portions of river drainages. Remarks All samples of C. macrolepidotus examined in the present study, with one exception, originated in the Rio Negro, Río Orinoco and in the Atlantic drainages of Guyana and Suriname. A single sample (UMMZ 204688) is from a southern locality, in the Río Baures, a tributary of the Rio Guaporé, along the Bolivian- Brazilian border (indicated by 2 in Fig. 9). The series of 15 specimens from this locality have a cranial fontanel, lack any conspicuous body pigmentation such as a longitudinal stripe and / or a humeral blotch and cannot be distinguished from the population samples of C. macrolepidotus from the Rio Negro, Río Orinoco and the Guianas. Therefore, they were tentatively identified as C. macrolepidotus; this population sample occurs sympatrically with C. guaporensis, the only other Chalceus species that occurs in the Rio Guaporé drainage. This record represents a major range extension to the south for that species. A similar disjunct distribution pattern was reported by Vari & Harold (2001) for Creagrutus maxillaris (Myers). The description of Chalceus ararapeera Cuvier & Valenciennes, 1850 was based on two specimens collected by Robert Schomburgk in the Essequibo River in Guyana. These two syntypes (MNHN A 9830) (Fig. 8) were examined in the present study and although in poor condition have a cranial fontanel and can be identified as C. macrolepidotus (Fig. 7). The only other species that occurs in Guyana is C. epakros, which lacks a cranial fontanel. Chalceus ararapeera is herein considered a junior synonym of C. macrolepidotus as first proposed by Günther (1864: 333). The type locality of C. macrolepidotus is indicated as originating in Brazil. The specimen on which Cuvier (1817) based the original description of the species was originally deposited in the ‘ Cabinet de Lisbonne’ (Lisbon, Portugal). At the beginning of the 19 th century, this and additional specimens from that collection were transferred to MNHN, Paris. They were originally collected by the Brazilian naturalist Alexandre Rodrigues Ferreira in the Brazilian Amazon (Vanzolini, 1996: 196 – 197). The generic placement of Creagrutus pellegrini Puyo (1943: 143) was discussed by Vari & Harold (2001: 43) who suggested that it should be assigned to Chalceus and considered it to be a doubtful species, C. pellegrini, following Myers (1960: 211). We follow these authors in assigning the species to Chalceus. The question of the taxonomic status of Chalceus pellegrini (Puyo) is somewhat difficult to address in view of the apparent loss of type material of various species described by Puyo (Géry, 1959: 345) and the lack of information in Puyo’s (1943: 143) description which would permit an unambiguous identification of the species. In addition, and as was also pointed out by Myers (1960: 211), Puyo (1949: 128 – 130) provided a description for C. macrolepidotus Cuvier following that of Creagrutus pellegrini, but surprisingly failed to recognize any relationship between the two nominal forms. Puyo (1943: 143) described C. pellegrini on the basis of two specimens, one from the Fleuve Maroni and one from Fleuve Itany in French Guiana. Based solely on Puyo’s description it is impossible to readily determine whether the specimens he examined represent C. macrolepidotus or C. epakros, the two Chalceus species known to occur in the Guianas. The currently known distribution of C. macrolepidotus and C. epakros in the Guianas helps to resolve this problem. Of the two species, only C. macrolepidotus has been reported in the Fleuve Maroni system (Planquette et al., 1996: 230). In addition, C. macrolepidotus also occurs in the Corantijn River in Suriname and in the Essequibo River in Guyana. Chalceus epakros has a more restricted distribution in the Guianas, being recorded only from the middle Essequibo River. Therefore, we consider Creagrutus pellegrini to be a junior synonym of Chalceus macrolepidotus (see Géry, 1977: 654). Material examined Type material. MNHN 2634, 1, 244.6 mm SL, Brazil, holotype of Chalceus macrolepidotus Cuvier, 1817; MNHN A 9830, 2, 66.9 – 80.2 mm SL; Guyana, Essequibo River, syntypes of Chalceus ararapeera Cuvier & Valenciennes, 1850. Non-type material. BRAZIL: AMAZONAS: MZUSP 44570, 2, 100.9 – 141.0 mm SL; Rio Negro, São João, near Tapurucuara. MZUSP 20201, 3, 104.0 – 123.0 mm SL; Rio Negro, Rio Jauaperi, from mouth to 100 km upstream. MZUSP 43291 (*), 7, 183.2 – 227.8 mm SL; Rio Negro, Cantagalo. – MZUSP 59046, 1, 197.4 mm SL; Rio Negro, lake in São João, near Tapurucuara. – MZUSP 58962 (*), 2, 206.9 – 210.5 mm SL; Rio Negro, Cantagalo, floodplain lake. – MZUSP 62223, 2, 71.9 – 72.1 mm SL; lagoon in island of Rio Negro, Paricatuba. – MZUSP 63649, 3, 84.5 – 129.0 mm SL; Rio Uaupés. – MZUSP 66482, 2, 91.6 – 96.2 mm SL; Rio Tiquié, c. 1 h downriver from the Indian community of Cunuri, below Cachoeira do Tucano. – CAS 156171, 1, 49.9 mm SL; Rio Negro or Río Orinoco. – CAS 156172, 1, 86.1 mm SL; Rio Negro, Caranguejo, above São Gabriel. – CAS 156170, 1, 95.7 mm SL; CAS 156830, 3, 149.0 – 168.0 mm SL; Rio Negro, Bucuri. – INPA 16950, 6, 175.0 – 221.0 mm SL; Rio Jaú, Lago Ibama.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	materials_examined	GUYANA: ANSP 176678, 1, 200.3 mm SL; Siparuni River, Tumbledown Rapids. FMNH 59467, 2, 166.7 – 198.0 mm SL; FMNH 7473, 1, 161.6 mm SL; AMNH 7082, 1, 178.0 mm SL; USNM 66156, 1, 161.0 mm SL; FMNH 53479, 5, 67.4 – 200.2 mm SL; FMNH 69807, 2, 75.3 – 188.3 mm SL; lower Potaro River, Tumatumari. – CAS 69079, 1, 65.1 mm SL; Essequibo River drainage, above the falls at Tumatumari Cataract. – CAS 121888, 1, 164.0 mm SL; Potaro River at Tumatumari Cataract. – AMNH 14331, 15, 82.4 – 105.4 mm SL; AMNH 214975, 6, 70.5 – 84.7 mm SL; AMNH 13399, 2, 35.5 – 57.5 mm SL; AMNH 14322, 1, 104.3 mm SL; Essequibo River, Rockstone. – AMNH 214938, 6, 35.8 – 43.4 mm SL; junction Mazaruni-Cuyuni and Essequibo Rivers, Bartica. – AMNH 43352, 9, 31.1 – 60.7 mm SL; BMNH 1936.4.4.5 – 6, 2, 41.4 – 44.9 mm SL; Essequibo, Bartica. – CAS 69081, 3, 160.0 – 190.0 mm SL; BMNH 64.1.21.46, 1, 134.2 mm SL; Essequibo River drainage. – CAS 69084, 2, 76.6 – 90.1 mm SL; Essequibo River drainage, Konawaruk pool, near the mouth of the Konawaruk River. – FMNH 53477, 3, 67.6 – 104.5 mm SL; Konawaruk. – FMNH 53478, 3, 74.2 – 83.4 mm SL; Gluck Island. – CAS 69086, 2, 83.3 – 84.7 mm SL; Essequibo River channels around Gluck Island, near Rockstone. – AMNH 216222, 1, 171.0 mm SL; headwaters between Mandi and Kuyuwini rivers, Essequibo River drainage. – AMNH 73020, 1, 54.2 mm SL; sandbar on north bank Cuyuni River, just upstream of Caowry Creek, Essequibo. – AMNH 220375, 2, 56.9 – 76.5 mm SL; USNM 94124, 1, 135.2 mm SL; Essequibo River drainage, Kartabo. – AMNH 221068, 2, 22.0 – 27.5 mm SL; Akima Island. – BMNH 1972 – 10.17: 1438, 1, 68.1 mm SL; Amatuk Creek, Potaro River. – BMNH 1972 – 10.17: 1440, 2, 66.5 – 68.5 mm SL; Kanaima Creek, Potaro River. – AMNH 16792, 3, 77.6 – 88.1 mm SL; AMNH 14313, 4, 88.5 – 101.2 mm SL; unspecified localities in Guyana. SURINAME: AMNH 16421, 1, 168.0 mm SL; BMNH 70.3.10.53, 1, 55.3 mm SL; unspecified locality in Suriname. – AMNH 54870, 5, 89.1 – 95.3 mm SL; Toeboeroe Creek. – AMNH 54810, 2, 67.2 – 90.5 mm SL; Dalbana Creek, 150 m upstream from junction with Kabelebo River. – USNM 226115, 46, 58.0 – 127.9 mm SL; Corantijn River at km 180, side channel of main river along Surinamese shore. – USNM 226114, 1, 198.0 mm SL; Corantijn River, Matapi Creek. – USNM 225373, 1, 76.4 mm SL; Corantijn River, about 2 km N of Matapi. VENEZUELA: AMAZONAS: ANSP 161220 (*), 1, 164.4 mm SL; Río Iguapo c. 1 h. above its mouth, Río Orinoco drainage. – ANSP 161221, 2, 131.7 – 138.0 mm SL; Rio Ventuari c. 12 km from its confluence with Río Orinoco. – ANSP 161223, 2, 89.1 – 125.5 mm SL; Río Pamoni, lagoon c. 0.5 km from confluence of Río Casiquiare. FMNH 103882, 1, 84.8 mm SL; backwater and beach of Río Atabapo c. 40 ft above mouth. – FMNH 103883, 2, 79.1 – 98.9 mm SL; Río Atabapo (pools) c. 1.2 h. above San Fernando de Atabapo. – FMNH 103885, 1, 76.9 mm SL; Río Autana at Playa Cucurito. – FMNH 103884, 1, 164.9 mm SL; Caño Guasuripana at Guasuripana, tributary of Río Atabapo, c. 7 min from San Fernando de Atabapo. – FMNH 103886, 3, 77.3 – 91.8 mm SL; pool of Río Ventuari above mouth in Río Orinoco Laguna Pavon. – FMNH 103881, 2, 80.9 – 89.9 mm SL; Caño Tuparero c. 2.5 h above San Fernando de Atabapo in Río Orinoco. – MZUSP 62454, 1, 125.8 mm SL; lagoon on Río Pamoni, c. 0.5 km from mouth in Río Casiquiare. – CAS 154592, 1, 92.2 mm SL; Río Casiquiare. – MZUSP 62455, 2, 78.8 – 92.5 mm SL; Laguna Pavon in pond behind beach of Río Ventuari, c. 30 min. from mouth. APURE: ANSP 165684, 4, 74.2 – 170.4 mm SL; Caño Potrerito, 24 km S of Rio Cinaruco on San Fernando de Apure, Puerto Paez Highway. – FMNH 69909, 1, 104.1 mm SL; FMNH 69910, 13; Río Cinaruco. – USNM 270135, Balneario Pozo Azul, c. 1 km E of Puerto Ayacucho to Solano road. BOLIVAR: MZUSP 62456, 2, 83.6 – 87.5 mm SL; Departamento Cedeño, mouth of caño tributary to Río Nichare. – FMNH 85686, 6, 122.6 – 125.8 mm SL (1 C & S); Río Orinoco drainage, 50 km toward Puerto Ayacucho from Puerto Nuevo. The following sample is tentatively identified as Chalceus macrolepidotus (see ‘ Remarks’, above): BOLIVIA: UMMZ 204688, 15, 70.7 – 91.0 mm SL; El Beni: Río Baures at mouth on right bank, 6 km SW of Costa Marques, Brazil.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	diagnosis	Diagnosis The presence of a conspicuous rounded humeral spot with a notch on its posterodorsal margin, the dark pelvic and anal fins and the presence of dark chromatophores on the posterior margin of the longitudinal series of scales posterior to the humeral spot distinguishes C. erythrurus (Fig. 10) from its congeners (in some sexually mature specimens, the humeral spot may be obliterated by a wide dark longitudinal band, see ‘ Comments ... ’, below) (Fig. 11). Although C. spilogyros also has a rounded humeral spot, that spot is not notched and is relatively smaller than the spot in C. erythrurus. A humeral spot is present in C. guaporensis and sometimes in C. epakros, however, in these species it is usually rounded to vertically elongate and located deeper in the skin being consequently less conspicuous than the humeral spots of C. erythrurus and C. spilogyros in which the spot is located superficially on the skin (see ‘ Comments ... ’, below). In addition, the caudal-fin lobes in C. erythrurus are robust and rounded compared to the more elongate and slender lobes in all other Chalceus species. Description Morphometric data presented in Table 2 (some meristic data for holotype not recorded due to poor condition of specimen). Maximum size 213.5 mm SL. Body robust, relatively elongate, greatest body depth located slightly anterior to dorsal-fin origin. Dorsal profile of head straight from snout tip to end of supraoccipital spine in all specimens. Anterior profile of head distinctly rounded from dorsal view. Interorbital distance wide, proportionally wider relative to body size in larger specimens. Dorsal surface of head in interorbital region flat. Dorsal body profile straight to slightly convex from tip of supraoccipital spine to dorsal-fin origin. Dorsal body profile posteroventrally inclined along dorsal-fin base, straight to relatively convex to adipose fin and concave along dorsal profile of caudal peduncle to origin of procurrent caudal-fin rays. Overall dorsal body profile of juveniles up to 40 mm SL convex. Ventral profile of head strongly convex to pectoral-fin, slightly convex to somewhat straight to pelvic-fin insertion, convex to anal-fin origin. Body profile along anal-fin base posterodorsally inclined and slightly concave along ventral margin of caudal peduncle. Head robust. Dorsal surface of head with distinct median fontanel restricted to small region anterior to the epiphyseal bar between frontals and completely separating parietals. Fontanel wide in small specimens and progressively narrower in larger individuals. Fontanel almost completely closed in a 213.5 - mm SL specimen but with small space remaining between contralateral parietals. Mouth large, terminal, slightly superior, upper and lower jaw of equal length. Maxilla not reaching vertical through anterior margin of orbit. Supramaxilla present. Dorsal-fin rays (ii, 10; ii, 11 in one specimen, n = 102). Dorsal-fin origin located posterior to vertical through insertion of innermost pelvic-fin rays. First basal dorsal-fin pterygiophore inserting behind neural spine of 12 th vertebra 9 (n = 1). Distal margin of dorsal fin nearly straight to convex. Adipose fin present. Anal-fin rays (iii, 9; iii, 8 in one specimen, n = 98). First basal anal-fin pterygiophore inserting behind haemal spine of 25 th vertebra (n = 1). Distal margin of anal fin straight to emarginate with anterior branched rays approximately 3 times length of ultimate ray. Pectoral-fin rays (range i, 15 – 18, mean 16.5, n = 104). Pectoral-fin pointed distally, with unbranched- and first branched rays longest and not reaching pelvic-fin insertion. Pelvic-fin rays i, 8 (i, 8; i, 7 in 3 specimens, i, 9 in one specimen, n = 102); fin pointed distally. Caudal fin forked, with lobes robust and rounded, lower fin lobe slightly more developed than upper lobe. Premaxillary teeth in three rows. Outer row 8 (range 6 – 9, 10 in one specimen, mean 7.6, n = 104) with teeth tricuspid or pentacuspid in large specimens and smaller specimens with conical or tricuspid teeth, with medial cusp larger. Tooth close to premaxillary symphysis slightly larger than other teeth in series. Remaining teeth of similar size, but with one or two lateralmost teeth slightly smaller. Cusps slightly curved with concave portion facing mouth cavity. Inner row 5 (range 5 – 6, mean 5.1, n = 104) with largest, symphyseal tooth usually asymmetric with one cusp on medial margin and two on lateral margin of tooth. Remaining teeth penta- or heptacuspid in large specimens, with second tooth from symphysis larger. Teeth tricuspid in small specimens, with teeth gradually diminishing in size laterally. Cusps slightly curved with concave portion opposite of mouth cavity. Intermediate row 2 (2, n = 105) pentacuspid (rarely tricuspid) teeth more widely separated than those of other rows and of intermediate size. Cusps straight. Maxillary teeth 9 (range 7 – 10, with one specimen each having 5, 11 and 12, mean 8.5, n = 93) with smaller specimens usually with higher numbers of teeth. First tooth pentacuspid followed by tricuspid and conical teeth distally. Teeth not extending along entire margin of ossification in large specimens. In small specimens teeth conical and extending along entire margin of ossification. Dentary teeth in two rows. Outer row 8 (range 7 – 11, 12, 13 and 16 in one specimen each, mean 9.4, n = 105). Teeth large and pentacuspid anteriorly, sometimes heptacuspid in large specimens, tricuspid in small specimens, gradually diminishing in size and number of cusps posteriorly. Posteriormost teeth conical. Cusps slightly curved with concave portion facing mouth cavity. Inner row consisting of large conical symphyseal tooth followed by series of minute conical teeth. First tooth originating behind fourth to fifth tooth of outer row with consequent gap between the symphyseal tooth and first minute conical tooth. Scales cycloid, large overall and approximately twice as large above lateral line as below it. Circuli on exposed portion of scales not concentric with those of anterior portion. Circuli on exposed portion of scales straight and extending to posterior margin of scale in small specimens; disorganized and with labyrinthic pattern in specimens around 200 mm SL. Radii originating on centre of scale and radiating anteriorly and posteriorly on scale surface. Lateral line low on body sides, complete, with alternating large and small perforated scales from posterior margin of opercle to vertical through base of last anal-fin ray; scales smaller and of similar size from that point to end of caudal peduncle. Canals in large specimens with 3 – 7 elevated branches (usually 3 or 4), forming ridges on scale surface; ridges more evident on region of the caudal peduncle. Number of branches decreases towards caudal peduncle, with canals of posterior scales unbranched. Small specimens (less than 140 mm) with branching pattern less developed. Lateral-line scales (range 36 – 39, 35 in two specimens, mean 37.2, n = 97). Scale rows between dorsal-fin origin and lateral line 3; between lateral line and pelvicfin insertion 2. Scales around caudal peduncle 12. Vertebrae 37 (n = 1). Colour in life. (Description based on photograph in Géry, 1977: 332, and personal observations of one specimen kept in aquarium). Overall coloration of head and body bright silver. Conspicuous humeral spot present on region of four first scales along longitudinal series just above lateral line. Overall shape of humeral spot rounded with notch on posterodorsal margin of spot. Dorsal portion of eye yellow. Dorsal profiles of head and body darker. Margins of scales on dorsal portions of body with strong concentration of dark chromatophores, forming well-defined reticulate pattern. Caudal fin bright red. Pelvic and anal fins distinctly yellow. Adipose and dorsal fins yellowish, both tinged with red. Pectoral fin hyaline. Colour in alcohol. Few specimens that retain guanine on body and head have silvery ground coloration. Most specimens only retain silvery pigmentation on infraorbital and opercular regions. Ground coloration of head and body in specimens ≥ 50 mm SL, lacking guanine on scales, yellowish to tan, darker dorsally. Conspicuous humeral spot on region of first four scales of longitudinal series just above lateral line. Overall shape of spot rounded with notch on its posterodorsal margin. Margins of scales on dorsal portions of body with strong concentration of dark chromatophores, forming well-defined reticulate pattern, that may be present over entire dorsal region of body, or restricted to dorsal portion of lateral-line scales and on longitudinal series just above it. Dark chromatophores scattered over infraorbitals and opercular region. Reticulate pattern less evident in large specimens and sometimes restricted to series of longitudinal diffuse dark patches. Pelvic and anal fins dark. Dorsal, adipose and caudal fins dusky. Some specimens with dark tips on caudal-fin rays. Some specimens (AMNH 58440, INPA 16190 (4 of 5), INPA 17226, INPA 18620; MZUSP 13533, MZUSP 20385 (4 of 9) and MZUSP 77595) have dark and wide longitudinal band along body (Fig. 11) (see ‘ Comments ... ’, below). Ground coloration of specimens £ 50 mm pale yellowish (Fig. 12). Reticulate pattern on scales more conspicuous than in larger specimens and extending to longitudinal series of scales below lateral line. Humeral spot small, rounded and somewhat elongated vertically. Dark narrow longitudinal line from dorsal margin of humeral spot to end of caudal peduncle. Pelvic, dorsal, anal, adipose and lower lobe of caudal fin dark. Pectoral fin hyaline. Distribution Rio Amazonas and Rio Solimões from Manaus to the Río Ucayali drainage in Peru (Fig. 14). Localities distributed mainly along main channel of Rio Amazonas and Rio Solimões and mouths of their tributaries. Remarks Fowler (1906: 444) described Pellegrinina heterolepis on the basis of one specimen that he believed originated from West Africa; as a consequence, he made comparisons of that nominal form with the African alestid genera Alestes, Brycinus and Brachyalestes in the diagnosis of the species. Subsequently the locality was shown to be incorrect and the fish was identified as a Chalceus species from South America (Géry, 1977: 18). The holotype of Pellegrinina heterolepis (ANSP 8150) was examined in the present study (Fig. 13) and on the basis of the presence of a humeral spot with a notch along its posterodorsal margin it is readily identified as Chalceus erythrurus. Additional characters present on the specimen that also characterize C. erythrurus are the presence of a cranial fontanel, the dark pelvic and anal fins and the first small inner dentary row tooth originating behind the fifth tooth of the anterior outer tooth row with a gap between the symphyseal tooth and minute first conical tooth. Based on these features, Pellegrinina heterolepis is herein considered to be a junior synonym of Chalceus erythrurus. Nakashima (1941: 76) described Chalceus macrolepidotus iquitensis from the surroundings of Iquitos, in the Peruvian Amazon, but did not provide any explanation as to why he recognized the material as a new subspecies. No information about type specimens was provided and no types are known to be extant. Based on his description, especially regarding the colour pattern and the shape of the humeral spot in the illustrated specimen, the species is most probably Chalceus erythrurus. Chalceus epakros also occurs in the Peruvian Amazon, but the humeral spot is usually absent in this species and when present it is less conspicuous than that of C. erythrurus and is, furthermore, more vertically elongate. In addition, C. epakros does not exhibit the reticulate pattern on the scales described by Nakashima (1941) which is, however, present in C. erythrurus. Chalceus macrolepidotus iquitensis Nakashima is therefore considered to be a synonym of C. erythrurus. Material examined Type material. ANSP 8032, 1, 44.5 mm SL; Peru, Río Ambyiacu (= Ampiyacu) at Pebas; holotype of Plethodectes erythrurus Cope, 1870 (specimen in very poor condition). – ANSP 8150, 1, 95.8 mm SL; Probably West Africa (?) [locality data incorrect, specimen from South America, see Géry, 1977: 18]; holotype of Pellegrinina heterolepis Fowler, 1906. Non-type material. BRAZIL: AMAZONAS: INPA 16928, 1, 195.0 mm SL; Rio Amazonas, Ilha do Careiro, Lago do Mingal. - INPA 16190 (*) 5, 119.7 – 158.7 mm SL; INPA 16929, 1, 189.0 mm SL; Rio Amazonas, Ilha do Careiro, Terra Nova. - INPA 18619, 1, 92.1 mm SL; Mamirauá Lake system, Paraná Maiana station A, 2.5 km from Comunidade Boca do Mamirauá; INPA 18620 (*), 3, 102.9 – 176.0 mm SL; Rio Solimões, Lago Capivara, Costa das Capivaras. - MZUSP 6881, 12, 95 – 166.7 mm SL; MZUSP 64203, 1, 106.8 mm SL; USNM 308376, 2, 38.3 – 39.1 mm SL; USNM 308820, 7, 28.7 – 37.9 mm SL; USNM 308371, 1, 1, 106.7 mm SL; USNM 308596, 1, 50.1 mm SL; Lago Janauari, right margin of Rio Negro, Manaus. – INPA 16949, 3, 75.6 – 88.6 mm SL; Janauari. – MZUSP 75610, 1, 89.4 mm SL; Lago Janauari, near Canta Galo. – MZUSP 75611, 2, 86.9 – 85.4 mm SL; Lago Janauari, near its mouth. – MZUSP 75612, 2, 79.6 – 88.1 mm SL; Lago Janaurai, first brick factory. – MZUSP 6707, 35, 94.7 – 136.3 mm SL; Rio Negro, vicinity of Manaus. – MZUSP 6462, 3, 160.7 – 213.5 mm SL; Lago Jacaré, right margin of Rio Solimões, above Manacapuru. – MZUSP 20053, 1, 161.7 mm SL; Lago do Rei, Ilha Canini, in front of Santo Antonio do Içá. – MZUSP 27297, 2, 95.5 – 104.2 mm SL; Paranã do Lago Amanã, lower Rio Japurá. – MZUSP 27296, 6, 84.4 – 112.5 mm SL (1 C & S); Costa Japão, Ressaca do Japão, lower Rio Japurá. – MZUSP 27298, 4, 140.0 – 145.9 mm SL; Lago Mamirauá, mouth of Rio Japurá. MZUSP 13533 (*), 1, 195.9 mm SL; Lago do Miguel, below Itacoatiara. – MZUSP 20385 (*) 1, 109.6 mm SL; Lago Janauacá. – CAS 139277, 5, 158.0 – 166.0 mm SL; Rio Solimões, Lago Coari. – CAS 69083, 2, 174.3 – 187.7 mm SL; Manaus. – INPA 17226 (*), 2, 157.0 – 190.0 mm SL; MZUSP 77595, 3, 158 – 178 mm SL; Rio Purus, Paraná do Lago Jacaré. – INPA 17235, 1, 186.0 mm SL; Rio Purus, Igarapé do Sacado. – INPA 17240, 1, 177.0 mm SL; Rio Purus, Beruri, at mouth of lake. – INPA 17257, 1, 84.0 mm SL; Rio Purus, Beruri, Paraná do Seixo. – INPA 17294, 1, 172.0 mm SL; Rio Purus, Beabá. – AMNH 12556, 1, 82.2 mm SL; vicinity of mouth of Rio Embira, tributary of Rio Tarauacá, Rio Juruá. – MZUSP 75614, 1, 118.8 mm SL; São José, Lago do Castanho, Janauacá. – USNM 229093, 1, 95.8 mm SL; Paraná do Lago Janauacá, entrance of Castanho. – USNM 308821, 3, 72.8 – 101.1 mm SL; Lago Murumuru, Lago Janauacá, near INPA stable. – USNM 308807, 2, 87.2 – 90.6 mm SL; MZUSP 75613, 6, 84.8 – 100.4 mm SL; Lago Murumuru, Lago Janauacá, at stable, near Manaus. – USNM 229083, 2, 86.4 – 98.2 mm SL; Lago Murumuru, at stable, near Manaus. – USNM 119947, 18, 92.6 – 126.0 mm SL; Rio Solimões, Codajás. – BMNH, 1929.11.18.3, 1, 189, 6 mm SL; Manaus, Rio Amazonas. – BMNH, 1925.10.28.85 – 84, 5, 87.8 – 195.3 mm SL; Rio Solimões, Manacapuru.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	materials_examined	PERU: LORETO: CAS 69082, 4, 147.7 – 172.0 mm SL; Río Amazonas drainage, Iquitos. – CAS 69074, 6, 92.2 – 128.1 mm SL; Río Amazonas drainage, Yarinacocha, lake connected to Río Pacaya. – CAS 136871, 6, 66.3 – 87.7 mm SL; Caño Tuye, Pebas. – CAS 17272, 2, 86.8 – 141.5 mm SL; Caño Chancho, near Pebas. – MZUSP 78064, 1, 139.0 mm SL; Río Yarapa, tributary of Río Ucayali, tributary of Río Amazonas, several sites along a 10 - km stretch of river. – AMNH 218032, 1, 79.9 mm SL; Río Itaya, near Iquitos. – USNM 167798, 4, 113.7 – 124.9 mm SL; Yarinacocha. – USNM 280437, 1, 99.5 mm SL; Río Itaya, main river channel and lower portion of caños, 5 – 20 km upstream of Belen, Iquitos. – USNM 280441, 3, 74.4 – 81.7 mm SL; green water caño on leftbank of Río Manite, about 8 km upriver of junction of Río Manite and Río Amazonas. – FMNH 70229, 3, 90.3 – 116.8 mm SL; Río Maniti, Santa Cecilia 20. – FMNH 100438, 1, 105.4 mm SL; Río Airico, 5 km above mouth in Río Chambira. AMNH 58440 (*), 1, 105.9 mm SL; South America, no locality data.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF9FFFD8FC487AF1FB48FD87.taxon	description	CHALCEUS SPILOGYROS SP. NOV. (FIGS 14 – 17; TABLE 3) Diagnosis The presence of a dark rounded humeral spot readily distinguishes C. spilogyros (Figs 15 – 17) from C. macrolepidotus and C. epakros. Chalceus spilogyros shares with C. erythrurus the presence of a humeral spot formed by dark chromatophores located superficially on the skin. However, the spot of C. spilogyros is rounded and relatively small compared with the larger spot of C. erythrurus; in the latter, there is also a notch along its posterodorsal margin. In addition, the caudal-fin lobes in C. spilogyros are relatively elongate and slender compared to the robust and rounded lobes of C. erythrurus. A humeral spot is present in C. guaporensis and sometimes in C. epakros; however, in these species it is usually rounded to vertically elongate, located deeper in the skin and thus somewhat less conspicuous than that of C. spilogyros. In addition, C. spilogyros lacks the longitudinal dark stripe characteristic of C. epakros and C. guaporensis, although in some specimens a wide dark longitudinal band is present. However, it differs from the band of C. epakros and C. guaporensis in the pattern of distribution of the chromatophores on the skin (see ‘ Comments ... ’, below). Description Morphometric data presented in Table 3. Maximum size 223.2 mm SL. Body robust, relatively elongate, greatest body depth located slightly anterior to dorsalfin origin. Dorsal profile of head distinctly convex anteriorly in snout region, posterodorsally inclined to convex from anterior end of snout to tip of supraoccipital spine and continuous with dorsal body profile. Anterior profile of head somewhat acute from dorsal view. Interorbital distance wide, proportionally wider relative to body size in larger specimens. Dorsal body profile somewhat convex to straight from tip of supraoccipital spine to dorsal-fin origin. Dorsal body profile posteroventrally inclined along dorsal-fin base, straight to relatively convex to adipose fin and concave along dorsal profile of caudal peduncle to origin of procurrent caudal-fin rays. Ventral profile of head distinctly convex along lower jaw. Ventral body profile gently convex from posterior limit of isthmus to analfin origin. Body profile posterodorsally inclined along anal-fin base, slightly concave along ventral margin of caudal peduncle. Head robust in specimens larger than 120 mm SL. Smaller specimens with relatively longer heads and more acute snout. Dorsal surface of head with distinct fontanel restricted to a small portion anterior to the epiphyseal bar between frontals and completely separating contralateral parietals. Fontanel wide in small specimens and progressively narrower in larger individuals. Small fontanel still present in largest examined specimen (223.2 mm SL). Mouth terminal, large, upper and lower jaw equally long. Maxilla extending approximately to vertical through anterior margin of orbit. Supramaxilla present. Dorsal-fin rays ii, 10 (ii, 10; ii, 9 in one specimen, ii, 11 in three specimens, n = 88). Dorsal-fin origin located posterior to vertical through insertion of innermost pelvic-fin rays. First basal dorsal-fin pterygiophore inserting behind neural spine of 13 th vertebra (n = 1). Distal margin of dorsal fin nearly straight to convex. Adipose fin present. Anal-fin rays iii, 9 (iii, 9; iii, 8 in one; iii, 10 in two specimens, n = 84). First basal anal-fin pterygiophore inserting behind haemal spine of 26 th vertebra (n = 1). Distal margin of anal fin straight to emarginate with anterior branched rays approximately 3 times length of ultimate ray. Pectoral-fin rays i, 15 (range 13 – 17, 18 in two specimens, mean 16.1, n = 88), pointed distally, with unbranched- and first branched rays longest, but not reaching pelvic-fin insertion. Pelvic-fin rays i, 8 (i, 8 n = 88), fin pointed distally. Caudal fin forked, with lobes slender particularly in specimens up to 120 mm SL, lower fin lobe slightly more developed than upper lobe. Premaxillary teeth in three rows. Outer row 8 (range 8 – 11, 7 in four specimens, mean 9.0, n = 88) either tricuspid or pentacuspid, with medial cusp larger. Tooth close to premaxillary symphysis slightly larger than other teeth of series. Remaining teeth of similar size with one or two lateralmost teeth slightly smaller. Cusps slightly curved with concave portion facing mouth cavity. Inner row 7 (range 6 – 7, 5 in four specimens, mean 6.2, n = 88), with largest, symphyseal tooth usually asymmetric with one cusp on medial margin and two on lateral margin of tooth. Remaining teeth, penta- or heptacuspid in large specimens, with second tooth from symphysis larger and remaining teeth gradually diminishing in size laterally. Cusps slightly curved with concave portion opposite of mouth cavity. Intermediate row, with 2 (2; 1 in one specimen, n = 88) pentacuspid teeth more widely spaced than teeth of other rows and of intermediate size. Cusps straight. Maxillary teeth 8 (range 7 – 11, 6 in two specimens, 12 in three specimens, mean 9.2, n = 88) with smaller specimens usually having more teeth. First teeth pentacuspid, followed by tricuspid and conical teeth distally. Teeth not extending along entire margin of ossification in large specimens. In small specimens conical and extending almost along entire margin of ossification. Dentary teeth in two rows. Outer row 12 (range 9 – 14, 8 and 17 in one specimen each, mean 11.0, n = 87), with teeth large and pentacuspid anteriorly, sometimes heptacuspid in large specimens and tricuspid in small specimens. Teeth gradually diminishing in size and number of cusps posteriorly. Posteriormost teeth conical. Cusps slightly curved with concave portion facing mouth cavity. Inner dentary row with large, conical, symphyseal tooth (tricuspid in a few larger specimens) followed by series of minute conical teeth. First small tooth usually situated behind fourth tooth of anterior row with gap between symphyseal tooth and first small conical tooth of rest of series. Scales cycloid, large overall and approximately twice as large above lateral line as below it. Circuli on exposed portion of scales not concentric with those of anterior portion. Circuli on exposed portion of scales straight and extending to posterior margin of scale in small specimens; disorganized and labyrinthic pattern in specimens around 200 mm SL. Radii originating on centre of scale and radiating anteriorly and posteriorly on scale surface. Lateral line low on body sides, complete, with alternating large and small perforated scales from posterior margin of opercle to vertical through base of last anal-fin ray. Lateral-line scales smaller and of similar size from that point to end of caudal peduncle. Canals in large specimens with 3 – 6 (usually 3 or 4) elevated branches, forming ridges on scale surface. Ridges more evident on region of caudal peduncle. Number of branches decreases toward caudal peduncle with posterior scales unbranched. Smaller specimens (£ 140 mm) with branching pattern less developed. Lateral-line scales 38 (range 36 – 39, 34 and 40 in one specimen each, mean 38.2, n = 79). Scale rows between dorsal-fin origin and lateral line 3; between lateral line and pelvic-fin insertion 2. Scales around caudal peduncle 12. Vertebrae 38 (n = 1). Colour in alcohol. All available specimens lack guanine on body except for few individuals that retain silvery pigmentation on infraorbital and opercular regions. Ground coloration of head and body yellowish to tan, darker dorsally. Conspicuous, small, rounded humeral spot on region of three first scales of longitudinal series just above lateral line. Humeral spot formed by dark chromatophores located superficially on skin (see ‘ Comments ... ’, below). Dark chromatophores scattered over infraorbitals and opercular region. Some specimens with dark blotch present on lower half of opercle. Scales of dorsal portion of body with chromatophores concentrated along posterior margin, more so in central portion and forming reticulate pattern, more conspicuous on two longitudinal series of scales above lateral line. Reticulate pattern more evident in specimens £ 150 mm SL (Fig. 16). All fins hyaline. Distal portion of longer caudal-fin rays darkened. Some specimens (MZUSP 7053 (5 of 7), MZUSP 20314 (1 of 55) and MZUSP 54568 (1 of 5 )) with dark, wide longitudinal band along body (Fig. 17) (see ‘ Comments ... ’, below). Distribution Occurs only in Rio Trombetas, lower Rio Tapajós and Rio Canumã in the Rio Madeira drainage (Fig. 14). Etymology Spilogyros, from the Greek spilos meaning spot and gyros, meaning circle, round, in reference to the rounded humeral spot of the species. Material examined Type material. HOLOTYPE: MZUSP 20314, 1, 208.0 mm SL; Brazil, Pará, Igarapé Jacaré, right margin of Rio Tapajós, near Boim. (3 ∞ 0 ¢ S; 55 ∞ 15 ¢ W). Collector Expedição Permanente à Amazônia, 27 / Oct / 1970. PARATYPES: MZUSP 76069 42, 1 C & S 86.2 – 214.0 mm SL; INPA 18589, 3, 100.3 – 201.0 mm SL; USNM 368278, 3, 107.1 – 196.0 mm SL; UMMZ 239930, 3, 106.8 – 183.0 mm SL; same data as holotype. Non-type material. BRAZIL. AMAZONAS: MZUSP 7054, 10, 92.3 – 134.8 mm SL; MZUSP 7053 (*), 7, 175.9 – 198.0 mm SL; Rio Canumã. PARÁ: MZUSP 15801 – 802, 2, 92.7 – 174.0 mm SL; MZUSP 15791 – 92, 2, 145.4 – 223.2 mm SL; Igapó do Lago Farias, Rio Trombetas, Reserva Biológica Trombetas. – MZUSP 54566, 2, 205.1 – 206.0 mm SL; MZUSP 54568 (*), 5, 149.4 – 195.7 mm SL; Lago Mussurá, left margin of Rio Trombetas, Porto Trombetas, Oriximiná. – MZUSP 54569, 2, 184.4 – 200.4 mm SL; MZUSP 54570, 1, 188.9 mm SL; Lago Batata, right margin of Rio Trombetas, Porto Trombetas, Oriximiná. – MZUSP 19698, 18, 77.7 – 148.6 mm SL; Lagoa Jacaré, Rio Trombetas. – INPA 16930, 2, 193.0 – 203.0 mm SL; Lago Cruz Alta, Rio Trombetas. – INPA 16943, 2, 165.0 – 210.0 mm SL; Lago Corusca, Igarapé do Braço, Rio Trombetas drainage. – INPA 16944, 4, 166.0 – 190.0 mm SL; Lago Jamari, Rio Trombetas drainage.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF8EFFD0FCB7791BFCFCF91A.taxon	diagnosis	Diagnosis	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF8EFFD0FCB7791BFCFCF91A.taxon	description	Description Morphometric data are presented in Table 4. Maximum size 175.6 mm SL. Body robust, somewhat compressed, relatively elongate, greatest body depth slightly anterior to dorsal-fin origin. Dorsal profile of head convex anteriorly on snout region, posterodorsally inclined from anterior end of snout to tip of supraoccipital spine. Anterior profile of head distinctly acute in dorsal view. Interorbital distance wide, proportionally wider relative to body size in larger specimens. Dorsal surface of head in interorbital region flat in specimens around 100 mm SL and smaller and slightly convex in larger specimens. Dorsal body profile convex from tip of supraoccipital spine to dorsal-fin origin. Dorsal body profile posteroventrally inclined along dorsal-fin base, straight to relatively convex to adipose fin and concave along dorsal profile of caudal peduncle to origin of procurrent caudal-fin rays. Ventral profile of head somewhat convex from tip of lower jaw to vertical through posterior limit of isthmus in specimens up to 120 mm SL, straight and posteroventrally inclined in larger specimens. Ventral body profile convex from posterior limit of isthmus to anal-fin origin. Body profile along anal-fin base posterodorsally inclined, slightly concave along ventral margin of caudal peduncle. Smaller specimens have larger head lengths relative to SL. Median fontanel between frontals and parietals absent in all samples including smallest specimens. Mouth terminal, large; upper jaw slightly longer than lower jaw, tip of premaxillary teeth extending below margin of upper lip, giving saw-like appearance to margin of premaxilla even in closed mouth. Maxilla extending to vertical through anterior margin of orbit. Supramaxilla present. Dorsal-fin rays ii, 10 (ii, 10; ii, 9 in one and ii, 11 in two specimens, n = 181). Dorsal-fin origin located posterior to vertical through insertion of innermost pelvic-fin rays. First dorsal-fin pterygiophore inserting behind neural spine of 11 th vertebra (n = 2). Distal margin of dorsal fin slightly straight to convex. Adipose fin present. Anal-fin rays iii, 9 (iii, 9; iii, 8 in 22 specimens, iii, 10 in one specimen, n = 177). First analfin pterygiophore inserting behind haemal spine of 23 rd vertebra (n = 2). Distal margin of anal fin straight to emarginate with anterior branched rays approximately 3 times length of ultimate ray. Pectoral-fin rays i, 16 (range 14 – 17, 12 in one and 13 in three specimens, respectively, mean 16.1, n = 175), pointed distally, with unbranched- and first branched rays longest, not reaching pelvic-fin insertion. Pelvicfin rays i, 8 (i, 8; i, 7 in 2 specimens, i, 9 in 4; n = 180), pointed distally. Caudal fin forked, lower fin lobe slightly more developed. Premaxillary teeth in three rows. Outer row 12 (range 9 – 13, 8 and 14 in one specimen each, mean 10.7, n = 180); tricuspid or pentacuspid, with medial cusp larger and all teeth of similar size. Cusps slightly curved with concave portion facing mouth cavity. Inner row 8 (range 7 – 10, 6 in 3 specimens; mean 8.0, n = 180); largest, symphyseal tooth usually asymmetric with one cusp on medial margin and two on lateral margin of tooth. Remaining teeth penta- or heptacuspid, with second tooth from symphysis larger and teeth gradually diminishing in size laterally. Cusps slightly curved with concave portion opposite of mouth cavity. Intermediate row 2 (2; 1 in five specimens, 3 in one specimen n = 180) pentacuspid teeth, more widely separated than teeth of other rows and of intermediate size. Cusps straight. Maxillary teeth 15 (range 9 – 16, 8 in 2 specimens, 17 in one, mean 12.6, n = 177). Anterior teeth tricuspid or conical posteriorly; teeth extending along almost entire margin of ossification. Dentary teeth in two rows. Outer row 11 (range 10 – 18, 9 in one specimen, 19 in 2; mean 13.3, n = 178), large and pentacuspid anteriorly, sometimes heptacuspid, gradually diminishing in size and number of cusps posteriorly. Posteriormost teeth conical. Cusps slightly curved with concave portion facing mouth cavity. Inner row teeth consisting of large, conical, symphyseal tooth followed by series of minute conical teeth. First small tooth originating very close to symphyseal tooth and forming an almost continuous series. Scales cycloid, large overall and approximately twice as large above lateral line as below it. Circuli on exposed portion of scales not concentric with those of anterior portion. Circuli on exposed portion of scales straight and extending to posterior margin of scale in small specimens; disorganized and labyrinthic pattern in specimens around 160 mm SL. Radii originating on centre of scale and radiating anteriorly and posteriorly on scale surface. Lateral line low on body sides, complete, with alternating large and small perforated scales from posterior margin of opercle to vertical through base of last anal-fin ray; scales smaller and of similar size from that point to end of caudal peduncle. Canals in large specimens with 1 – 6 branches. Number of branches decreases toward caudal peduncle with posterior scales unbranched. Small specimens (£ 150 mm) with branching pattern less developed. Lateral-line scales 35 (range 31 – 37, mean 34.3, n = 169). Scale rows between dorsal-fin origin and lateral line 3; between lateral line and pelvic-fin insertion 2. Scales around caudal peduncle 12. Vertebrae 34 (n = 1), 35 (n = 1). Colour in life. Description based on photographs taken by various collectors, Géry (1977: 329) and personal observation of 3 specimens kept in aquarium. Overall coloration of head and body bright silver. No conspicuous humeral spot. Dorsal portion of eye yellow. Central portions of scales on longitudinal series just above lateral line tinged with red, coloration less evident posterior to vertical through anal-fin origin. All fins (except pectoral) bright red. Pectoral fin hyaline. Three specimens kept in tanks exhibited rapid changes in coloration with fins turning pale under stressful conditions. Colour in alcohol. Few examined specimens retain guanine and have silvery reflections on body and head. Most only retain silvery pigmentation on infraorbital and opercular regions. Specimens lacking guanine on body yellowish to tan, darker dorsally. Longitudinal dark stripe extends from posterodorsal margin of opercle to caudal peduncle, but not reaching base of caudalfin rays. Stripe formed of dark chromatophores located deep in skin (see ‘ Comments ... ’, below); less evident in specimens retaining guanine on body. Small specimens with inconspicuous vertically elongate humeral spot extending over first three scales of lateral line (see ‘ Comments ... ’, below). Scales above lateral line with chromatophores slightly more concentrated along posterior margin forming fine reticulate pattern. Humeral spot and reticulate pattern progressively less evident in larger specimens. All fins hyaline, some specimens with dorsal and anal fins with scattered chromatophores. Most specimens with dark tips on adipose fin and dorsal- and caudal-fin rays. Distribution The species is widespread throughout the central and lower portions of the Amazon basin including the Rio Madeira, Rio Xingu, Rio Tapajós, Rio Negro, Rio Branco, Rio Trombetas and Rio Tocantins-Araguaia basins (Fig. 20). It also occurs in the middle and upper Río Orinoco basin, the Essequibo River in Guyana and in the Río Nanay in Peru (see ‘ Remarks’). Etymology Epakros, from the Greek for ‘ pointed at the end’, referring to the snout of the species. Remarks The single specimen of C. epakros (ANSP 175371) from the Essequibo River represents an extension to the north-east relative to the other records of the species. A major extension to the west is represented by samples from the Río Nanay, in the Peruvian Amazon. These samples could not be distinguished from those originating in the more central and eastern portions of the Amazon basin and are consequently considered conspecific despite the gap in the known distribution of the species. Material examined Type material. HOLOTYPE: MZUSP 33392, 1, 132.6 mm SL; Brazil, Pará, Rio Tapajós, São Luís, above Itaituba (4 ∞ 25 ¢ S; 56 ∞ 10 ¢ W). Collector M. Goulding, 22 / Oct / 1983. PARATYPES: MZUSP 76070, 53, 1 C & S, 110.1 – 150.7 mm SL; INPA 18590, 3, 119.1 – 129.6 mm SL; USNM 368279, 3, 121.8 – 138.4 mm SL; UMMZ 239931, 3, 128.4 – 136.2 mm SL; same data as holotype. Non-type material. BRAZIL: AMAZONAS: INPA 705, 2, 107.5 – 138.1 mm SL. – INPA 16931, 5, 129.6 – 148.4 mm SL; Rio Uatumã. – INPA 16965, 2, 124.1 – 131.7 mm SL; Rio Uatumã, mouth of Igarapé Catitu. – INPA 16960, 1, 162.0 mm SL; INPA 16963, 2, 128.0 – 145.5 mm SL; Igarapé da Arraia, Rio Uatumã. – INPA 16956, 1, 162.0 mm SL; Igarapé da Água Branca, Rio Pitinga. – INPA 18617, 7, 112.2 – 141.9 mm SL; Rio Pitinga, Cachoeira Travessão. – MZUSP 6706, 24, 93.7 – 156.0 mm SL; Rio Negro, surroundings of Manaus. – MZUSP 31341, 1, 103.9 mm SL; Rio Negro, Anavilhanas. PARÁ: INPA 16961, 2, 143.0 (from 1 spec.), Rio Jari, Igapó and margin of island in front of Porto Sabão. – INPA 16969, 9, 135.0 – 156 mm SL; Rio Jari, below Cachoeira de Santo Antônio. – INPA 4293, 2, 58.5 – 66.1 mm SL; Rio Xingu, Arroz Cru, Lagoa da Palmeira. – INPA 4181, 3, 70.7 – 72.8 mm SL; INPA 4133, 2, 117.1 – 132.9 mm SL; Rio Xingu, Ilha de Babaquara. – MZUSP 33394, 31, 125 – 175.6 mm SL; MZUSP 30758, 1, 81.6 mm SL; MZUSP 63651, 3, 127.0 – 146.1 mm SL; Rio Xingu, Belo Monte. – MZUSP 45884, 1, 125.3 mm SL; Rio Riozinho, Serra de Kukoinhokren. – MZUSP 36816, 1, 133.3 mm SL; Cachoeira do Espelho, Rio Xingu. – USNM 119949, 3, 98.1 – 178.8 mm SL; Rio Xingu, Porto de Moz. – INPA 6746, 3, 136.0 – 158.0 mm SL; Rio Jamanxim, tributary of Rio Tapajós, Ilha Terra Preta. – MZUSP 22095, 4, 86.4 – 95.3 mm SL; Rio Tapajós, Ilha da Barreirinha, near São Luís. – MZUSP 25431, 1, 88.4 mm SL; right margin of Rio Tapajós, in front of Pimental. – MZUSP 30750, 3, 127.0 – 133.0 mm SL; Rio Tapajós, between Itaituba and São Luís. – CAS 69080, 1, 88.5 mm SL; Rio Tapajós, Itaituba. – MZUSP 25503, 2, 102.9 – 108.5 mm SL, left margin of Rio Tapajós, between National Park headquarters and branch of Saita, km 67. – MZUSP 30754, 14, 1 C & S, 69.3 – 94.7 mm SL; Rio Tapajós, Pederneiras. – MZUSP 21992, 4, 114.4 – 128.5 mm SL; Rio Tapajós, São Luís, Poça de Pedra. – MZUSP 20276, 8, 103.8 – 115.6 mm SL; Rio Tapajós, inland lake in front of Monte Cristo. INPA 748, 1, 133.7 mm SL; Rio Curuá-Una. – INPA 16945, 1, 99.4 mm SL; INPA 16946, 2, 104.2 – 106.5 mm SL; INPA uncat., 10, 93.6 – 101.7 mm SL; Icangui, Rio Tocantins. – INPA 16947, 21, 79.1 – 103.8 mm SL; Rio Tocantins, below Tucuruí dam. – MZUSP 30751, 1, 133.2 mm SL; Rio Itacaiunas, Rio Tocantins, Caldeirão. – MZUSP 20364, 2, 71.5 – 77.2 mm SL; on marginal lagoons of Rio Tocantins, near Tucuruí. – MZUSP 20649, 2, 74.4 – 74.6 mm SL; Igarapé Muru, Rio Tocantins, below Tucuruí. – MZUSP 20324, 2, 71.9 – 77.0 mm SL; Igarapé Urubu, Rio Tocantins, near Posto Trocará. – MZUSP 20088, 2 77.8 – 97.5 mm SL; Rio Trombetas, Oriximiná. – INPA 16968, 2, 135.2 – 137.1 mm SL; INPA 16959, 4, 105.2 – 116.4 mm SL; Rio Trombetas, below Cachoeira Porteira. INPA 16948, 5, 131.7 – 144.4 mm SL; Rio Trombetas, above Cachoeira Porteira. – CAS 69075, 1, 102.5 mm SL; Rio Amazonas, market at Santarém. – CAS 69077, 3, 108.0 – 115.3 mm SL; Rio Amazonas, Marabá. GOIÁS: MZUSP 54571, 1, 132.0 mm SL; Rio Tocantins, Minaçú, Porto do Garimpo, below Serra da Mesa dam. – MZUSP 54572, 2, 105.3 – 122.3 mm SL; Rio Tocantins, Porto do Garimpo, below Serra da Mesa dam. MATO GROSSO: MZUSP 64960, 3, 118.0 – 130.3 mm SL; Ribeirão Suaizinho near Fazenda Cascavel, tributary of Rio Suiá-Missu, Rio Xingu. – INPA 16970 9, 87.6 – 99.0 mm SL; Rio do Côco, Caseara, Lago do Case. INPA 18602, 1, 89.5 mm SL, Rio do Côco; Caseara, Cantão. – INPA uncat., 21, 84.5 – 99.8 mm SL; Rio Araguaia, Fazenda Santa Fé. – INPA 18604, 4, 91.3 – 104.3 mm SL; Lago Santa Fé, Rio Araguaia; Cantão State Park. – INPA 18603, 1, 98.4 mm SL; Lago Ariranhas. – INPA 18605, 3, 87.6 – 88.2 mm SL; Porto Balsa, Rio Côco. – MZUSP 63650, 3, 117.4 – 125.7 mm SL; Rio Correntes, Rio Araguaia, Barra do Garça. – MZUSP 19631, 3, 73.9 – 108.8 mm SL; Rio Araguaia, Santa Terezinha. – MZUSP 3847, 1, 107.7 mm SL; Rio Araguaia. – MZUSP 64202, 5, 138.8 – 165.3 mm SL. – MZUSP 54445, 1, 109.1 mm SL; Rio Cristalino, Rio Araguaia. – MZUSP 62535, 4, 124.6 – 138.8 mm SL; Rio Teles Pires, Pesqueiro do Dentinho, município de Alta Floresta – USNM 31083, 5, 132.9 – 173.0 mm SL; Rio Batovi, small tributary and shallow lake drainage, Rio Xingu. Rondônia: INPA 16925, 3, 105.6 – 140.2 mm SL; Rio Jamari, c. 5 km above Samuel dam. – INPA 16967, 1, 79.9 mm SL; Rio Urupá, tributary of Rio Jiparaná (= Rio Machado). – INPA 16966, 2, 110.8 – 114.9 mm SL Rio Urupá, tributary of Rio Machado, c. 10 km above Jiparaná; INPA 16957, 2, 158.0 mm SL; Lago Espanha, below Samuel dam. – INPA 16962, 2, 139.0 – 158.0 mm SL; Igarapé Japiim, c. 45 km above Samuel dam. – MZUSP 14032, 5, 129.6 – 167.3 mm SL; Lago do Paraíso, Rio Machado, Rio Madeira. – MZUSP 77270, 1, 89.3, Panelas, Rio Roosevelt, above falls. RORAIMA: MZUSP 30752, 1, 128.3 mm SL; Cachoeira do Bem-Querer, Rio Branco. – MZUSP 30749, 5, 108.1 – 144.6 mm SL; Rio Uraricoera, Maracá. – INPA 8113, 1, 74, 7 mm SL; Igarapé number 1.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF8EFFD0FCB7791BFCFCF91A.taxon	materials_examined	COLOMBIA: AMNH 38183, 1, 118.9 mm SL, C & S; Amazon Basin. GUYANA: ANSP 175371, 1, 89.3 mm SL; Essequibo River, sandbars 1.0 – 1.5 h upstream from Maipuri campsite. PERU: LORETO: USNM 280438, 2, 67.3 – 77.1 mm SL; Río Nanay, c. 20 km upstream of mouth in the main channel. – USNM 280440, 1, 64.9 mm SL; Río Nanay, north-east of Iquitos. – USNM 240442, 1, 76.6 mm SL; Río Nanay at Nanay beach, West of Iquitos. – ANSP 167068, 1, 69.8 mm SL; Río Nanay, right bank, 0.5 mi below Santa Clara. – ANSP 167067, 2, 71.8 – 76.6 mm SL; Río Nanay, creek tributary of Río Nanay (above confluence) c. 0.25 mi below Santa Clara. – ANSP 136900, 5, 73.0 – 86.3 mm SL; ANSP 136901, 5, 70.8 – 86.3 mm SL; Vicinity of Iquitos, Moronacocha outlet, right bank of Río Nanay, c. 9 min above Río Amazonas. VENEZUELA: AMAZONAS: ANSP 161222, 1, 121.3 mm SL; Río Orinoco at playa across from mouth of Río Iguapo. – ANSP 161224, 1, 130.3 mm SL; Caño of Río Casiquiare, playa c. 1.5 h. from confluence of Río Casiquiare and Río Orinoco. – ANSP 159781, 1, 79.7 mm SL; Río Orinoco at El Burro. – ANSP 161219, 1, 130.1 mm SL; Río Orinoco, caño separating island and playa just downstream from Quiratare. BOLIVAR: ANSP 135641, 2, 71.8 – 89.1 mm SL; Caño Chuapo, c. 20 min downstream from Jabillae on Río Caura. – ANSP 139554, 5, 88.9 – 99.0 mm SL; isolated backwater of Río Nichare, c. 10 min from Río Nichare / Río Caura junction. – ANSP 159779, 1, 94.0 mm SL; Río Orinoco, vicinity of Puerto Las Majadas, Río Orinoco / Río Caura confluence. – ANSP 159780, 2, 92.1 – 101.3 mm SL; Río Caura at Puerto das Majadas. – ANSP 139559, 1, 119.5 mm SL; sand bar along Río Mato. CHALCEUS GUAPORENSIS SP. NOV. (FIGS 21 – 23; TABLE 5)	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF8EFFD0FCB7791BFCFCF91A.taxon	diagnosis	Diagnosis Chalceus guaporensis can be readily distinguished from all other Chalceus species except C. epakros by the lack of a median fontanel between the frontal and parietal bones, by the relatively longer and more acute snout and by the presence of a longitudinal dark stripe from the posterodorsal margin of opercle to caudal peduncle formed by chromatophores located deep in the skin (see ‘ Comments ... ’, below) (Figs 22, 23). Chalceus guaporensis differs from C. epakros in having 7 branched pelvic-fin rays (vs. 8 in the latter species, see ‘ Remarks’). It may be further distinguished from C. epakros and C. macrolepidotus in having the first small tooth of the inner dentary row located behind the fourth or fifth tooth of the anterior row with a distinct gap between the symphyseal tooth and first small conical tooth (vs. first small tooth of inner dentary row located very close to the symphyseal tooth and forming an almost continuous series). Chalceus guaporensis also has a somewhat rounded, conspicuous humeral spot extending over the first four scales of the lateral line and located deep in the skin (see ‘ Comments ... ’, below). A humeral spot located deep in the skin is sometimes present in C. epakros, although when present in the latter species it is usually more vertically elongate than the spot of C. guaporensis. Although there is broad overlap in the ranges, the number of lateral line scales in C. guaporensis tends to be higher than those in C. epakros (Table 6, Fig. 21). Description Morphometric data presented in Table 5. Maximum size 140.4 mm SL. Body robust, somewhat compressed, relatively elongate, greatest body depth located slightly anterior to dorsal-fin origin. Dorsal profile of head convex anteriorly at snout region, posterodorsally inclined from anterior end of snout to tip of supraoccipital spine. Anterior profile of head distinctly acute in dorsal view. Interorbital distance wide, proportionally wider relative to SL in larger specimens. Dorsal surface of head in interorbital region flat. Dorsal body profile convex from tip of supraoccipital spine to dorsal-fin origin. Dorsal body profile posteroventrally inclined along dorsal-fin base, then straight to relatively convex to adipose fin and concave along dorsal profile of caudal peduncle to origin of procurrent caudal-fin rays. Ventral profile of head somewhat convex from tip of lower jaw to vertical through posterior limit of isthmus. Ventral body profile convex from that point to anal-fin origin. Body profile along anal-fin base posterodorsally inclined, slightly concave along ventral margin of caudal peduncle. Smaller specimens with relatively longer heads. Median fontanel absent between frontals and parietals even in smallest examined specimens. Mouth terminal, large, upper jaw slightly longer than lower jaw, tip of premaxillary teeth extends below margin of upper lip giving a saw-like appearance to margin of premaxilla even in closed mouth. Maxilla extending to vertical through anterior margin of orbit. Supramaxilla present. Dorsal-fin rays ii, 10 (ii, 10; ii, 9 in one and ii, 11 in two specimens, n = 70). Dorsal-fin origin situated posterior to vertical through insertion of innermost pelvic-fin rays. First basal dorsal-fin pterygiophore inserting behind neural spine of 11 th vertebra (n = 3). Distal margin of dorsal fin slightly straight to convex. Adipose fin present. Anal-fin rays iii, 9 (iii, 9; iii, 8 in 2 specimens, n = 70). First basal anal-fin pterygiophore inserting behind haemal spine of 24 th vertebra (n = 4). Distal margin of anal fin straight to emarginate with anterior branched rays approximately 3 times length of ultimate ray. Pectoral-fin rays i, 14 (range 14 – 16, 17 in one specimen, mean 16.1, n = 70), pointed distally, with unbranched- and first branched rays longest, but not reaching pelvic-fin insertion. Pelvic-fin i, 7 (i, 7, n = 70); fin pointed distally. Caudal fin forked, lower fin lobe slightly more developed than upper lobe. Premaxillary teeth in three rows. Outer row 9 (range 9 – 12, mean 10.8, n = 68); teeth tricuspid, sometimes pentacuspid, with medial cusp larger and teeth of similar size. Cusps slightly curved with concave portion facing mouth cavity. Inner row 8 (range 7 – 10, 11 in 1 specimen; mean 8.5, n = 70) largest, symphyseal tooth usually asymmetric with one cusp on medial margin and two cusps on lateral margin of tooth. Remaining teeth pentacuspid, or more lateral teeth tricuspid, with second tooth from symphysis larger and teeth gradually diminishing in size laterally. Cusps slightly curved, with concave portion opposite of mouth cavity. Intermediate row 2 (2; 1 in one specimen, n = 70) pentacuspid or tricuspid teeth, more widely separated than teeth of other rows and of intermediate size. Cusps straight. Maxillary teeth 11 (range 9 – 16, 17 in one specimen, mean 12.5, n = 70). Anterior teeth tricuspid with remaining teeth conical. Teeth extending along almost entire margin of ossification. Dentary teeth in two rows. Outer row 14 (range 11 – 16, 18 in one specimen; mean 13.1, n = 70), with teeth large and pentacuspid anteriorly, sometimes heptacuspid, gradually diminishing in size and number of cusps posteriorly. Posteriormost teeth conical. Cusps slightly curved with concave portion facing mouth cavity. Inner row consists of large conical symphyseal tooth followed by series of minute conical teeth. First tooth usually positioned behind fourth or fifth tooth of anterior row with distinct gap between that tooth and symphyseal tooth. Scales cycloid, large overall and approximately twice as large above lateral line as below it. Circuli on exposed portion of scales not concentric with those of anterior portion. Circuli on exposed portion of scales straight and extending to posterior margin of scale in examined specimens. Radii originating on centre of scale and radiating anteriorly and posteriorly on scale surface. Lateral line low on body sides, complete, with alternating large and small perforated scales from posterior margin of opercle to vertical through last anal-fin ray; scales smaller and of similar size from that point to end of caudal peduncle. Canals in large specimens with 1 – 5 branches. Number of branches decreases toward caudal peduncle, with posterior scales unbranched. Small specimens with branching pattern less developed. Lateral-line scales 36 (range 35 – 37, 1 specimen with 34, 1 with 38; mean 36.1, n = 69). Scale rows between dorsalfin origin and lateral line 3. Scale rows between lateral line and pelvic-fin insertion 2. Scales around caudal peduncle 12. Vertebrae 35 (n = 3). Colour in alcohol. Specimens only retain silvery pigmentation on infraorbital and opercular regions. Body tan, darker dorsally. Longitudinal dark stripe formed by dark chromatophores located deep in the skin (see ‘ Comments ... ’, below). Stripe extends from posterodorsal margin of opercle to caudal peduncle, but not reaching base of caudal-fin rays. Somewhat rounded, conspicuous humeral spot extending over first four scales of lateral line and located more deeply in skin (see ‘ Comments ... ’, below). Dorsal portion of humeral spot overlapping longitudinal stripe. Scales above lateral line with chromatophores slightly more concentrated along posterior margin and forming fine reticulate pattern. Some specimens also have chromatophores scattered on lateral-line scales and one longitudinal series above it. All fins hyaline, with dorsal, anal and adipose with dark chromatophores scattered. Tips of caudal- fin rays and ventral margin of first principal ray of lower caudal-fin lobe dark. Distribution The Rio Guaporé and Río Mamoré drainages, Río Madre de Dios and Rio Jaci-Paraná in the upper Rio Madeira (see ‘ Remarks’) (Fig. 20). Etymology Named after the Rio Guaporé. Remarks The main trait that distinguishes C. guaporensis from C. epakros is the number of branched pelvic-fin rays (7 vs. 8, respectively). Among specimens of C. guaporensis examined in this study (Table 7, n = 71) all have 7. Additional specimens from Río Madre de Dios basin (MUSM 3756, n = 1; 3907, n = 1; 16850, n = 1; and 8033, n = 5), all have 7 except for one specimen (MUSM 8033) with 8 (H. Ortega, pers. comm.). The latter specimen is considered atypical and herein tentatively identified as C. guaporensis. Most of the C. epakros specimens (n = 174) have 8 rays (Table 7). Of the six remaining specimens, two have 7 (INPA 16968, 1 of 2, 137.1 mm SL, from the Rio Trombetas and INPA 16925, 1 of 3, 105 mm SL from the upper Rio Madeira); both belong to lots in which the other specimens have 8 and their number of lateral-line scales (34 and 36, respectively), falls within the range of variation for the two species (Table 6). The specimens from the Rio Trombetas all possess 8; that basin is, furthermore, distant from the distribution range of C. guaporensis. The specimen with 7 rays from the Rio Trombetas appears atypical and is herein assigned to C. epakros. The specimen from the upper Rio Madeira is somewhat more problematic because it comes from a location adjacent to the northern limit of the distribution range of C. guaporensis, raising the question as to whether C. epakros and C. guaporensis perhaps occur in sympatry along the edges of their distribution range, or whether the specimen is atypical. It was collected in the Rio Jamari, a tributary of the upper Rio Madeira below the waterfall region (a series of 19 waterfalls occurs along a 353 - km river stretch between the cities of Porto Velho in the upper Rio Madeira and Guajará-Mirim in the Rio Mamoré; Goulding, 1979: 33 – 34). Within the Rio Madeira basin, C. epakros appears to occur only in regions downstream of the waterfalls, while all specimens of C. guaporensis from the region of the upper Rio Madeira were collected upstream. Until additional information on these two species becomes available, we have tentatively assigned the specimen to C. epakros. Material examined Type material. HOLOTYPE: UMMZ 239851, 1, 112.0 mm SL. BOLIVIA: BENI: Río Itenez at mouth of Río Baures, 6 km SW of Costa Marques; 12 ∞ 31 ¢ S, 64 ∞ 19 ¢ W. Collector R. M. Bailey & R. Ramos, 30 / Sep / 1964. PARATYPES: BOLIVIA: BENI: UMMZ 204719, 4, 1 DS, 75.0 – 128.4 mm SL; MZUSP 76071, 3, 78.1 – 84.7 mm SL; same data as holotype. – UMMZ 204209, 19, 2 C & S 62.2 – 86.2 mm SL; MZUSP 76072, 4 62.3 – 81.4 mm SL; Río Itenez, opposite Costa Marques, 12 ∞ 29 ¢ 30 ¢¢ S, 64 ∞ 15 ¢ 30 ¢¢ W. – UMMZ 204783 9, 2 DS, 75.3 – 109.9 mm SL; Río Baures, 400 m above mouth on left bank, 6 km SW of Costa Marques; PERU: MADRE DE DIOS: USNM 319294, 7, 1 C & S, 122.3 – 133.4 mm SL; Manu National Park, Pakitza, Picaflor Stream, Cana Brava Trail # 19. Non-type material. BOLIVIA: BENI: UMMZ 205201, 3, 70.9 – 84.9 mm SL; slough of Río Itenez, 10 km SE of Costa Marques (Brazil). – UMMZ 204272 (2 of 4) 101.8 – 121.1 mm SL; Río Itenez at mouth of dry run, 2 km SE of Costa Marques (Brazil). – UMMZ 204447, 3, 73.2 – 78.1 mm SL; Río Itenez, along sand bar about 9 km SE of Costa Marques (Brazil). – UMMZ 204949, 1, 82.5 mm SL; playa pond of Río Itenez, 9 km SE Costa Marques (Brazil). – UMMZ 204588, 1, 67.8 mm SL; Río Itenez, 5 km SW of Costa Marques, 1.5 – 2 km above mouth of Río Baures. – UMMZ 204848 (1 of 3 specimens examined) 140.4 mm SL; Río Baures, 2 km above mouth. – UMMZ 233932, 1, 66.6 Río Baures at mouth, on right bank, 6 km SW of Costa Marques, Brazil. – FMNH 57585, 2, 95.0 – 97.6 mm SL; Villa Bella. – MNHN 1989 – 1426, 2, 124.2 – 126.3 mm SL. San Luis, Madre de Dios – AMNH 40169, 1, 102.9 mm SL; Río Mamoré at Cachuela, below Guayaramerin. – AMNH 40059, 21, 61.7 – 124.2 mm SL; Río Baures, 500 m above mouth. SANTA CRUZ: AMNH 77533, 1, 83.6 mm SL; Río Mamoré, c. 2 km north of Boca Chapare.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
623087C7FF8EFFD0FCB7791BFCFCF91A.taxon	materials_examined	BRAZIL: RONDÔNIA: FMNH 14988 – 14989, 2, 79.1 – 100.8 mm SL; FMNH 57584, 13, 77.3 – 126.9 mm SL; Rio Guaporensis, Maciel. – INPA 16927 1, 94.0 mm SL; Rio Jaci-Paraná, c. 3 km from town of Jaci-Paraná.	en	Zanata, Angela M., Toledo-Piza, Mônica (2004): Taxonomic revision of the South American fish genus Chalceus Cuvier (Teleostei: Ostariophysi: Characiformes) with the description of three new species. Zoological Journal of the Linnean Society 140 (1): 103-135, DOI: 10.1111/j.1096-3642.2004.00090.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2004.00090.x
