Corydoradinae

Dias, Angelica C., Tencat, Luiz F. C., Roxo, Fabio F., Gabriel, Souza, Silva, Costa, Santos, Sérgio A., Brito, Marcelo R., Taylor, Martin I. & Oliveira, Claudio, 2024, Phylogenomic analyses in the complex Neotropical subfamily Corydoradinae (Siluriformes: Callichthyidae) with a new classification based on morphological and molecular data, Zoological Journal of the Linnean Society 203 (3), pp. 1-31 : 4-13

Subfamily Corydoradinae

Genus Corydoras Lacépède, 1803

Corydoras Lacépède, 1803: 147–149 (type species: Corydoras geoffroy Lacépède, 1803 , by monotypy).

Cordorinus Rafinesque, 1815: 89 (unnecessary emendation of

Corydoras Lacépède, 1803 ).

Type species: Corydoras geoffroy Lacépède, 1803 , by monotypy.

Diagnosis: Corydoras can be distinguished from the remaining genera in Corydoradinae by having the following features: branch of the temporal sensory canal at sphenotic, which gives rise to the supraorbital canal, with two pores [ Fig. 9A ; see Tencat et al. 2021: 5, fig. 2(a)] (vs. one pore in remaining genera); upper tooth plate of branchial arch with three or four series of teeth (vs. two series in remaining genera; three series of teeth in some specimens of A. fuscogutatus Nijssen & Isbrücker, 1976 , A. mephisto , and A. raimundi ); area at the corner of the mouth, ventral to the maxillary barbel, with a roughly triangular fleshy flap ( Fig. 10 ), which can be variably elongated, similar to a barbel (see Fuller and Evers 2005: 232, structure labelled as ‘third rictal barbel’) (vs. fleshy flap absent); mesethmoid large in size (similar to the illustration by Brito 2003: 126, fig. 1A) (vs. conspicuously short in Gastrodermus , and short to moderate in size in Aspidoras , Hoplisoma , and Osteogaster ); posterior margin of dorsal-fin spine with serrations directed towards the tip of the spine [ Fig. 11B ; see Tencat et al. 2021: 5, fig. 2(b)] (vs. directed towards the origin of the spine in Brochis , except for B. difluviatilis ; most serrations perpendicularly directed in some Hoplisoma ; typically devoid of serrations in Aspidoras and Scleromystao ); posterior margin of pectoral-fin spine with conical serrations mostly directed towards the origin of spine, variably with some serrations perpendicularly directed or directed towards tip of spine [ Fig. 12B ; see Tencat et al. 2021: 5, fig. 2(c)] (vs. all or nearly all serrations directed towards the tip of the spine in most Hoplisoma and Osteogaster , plus G. hastatus and G. pygmaeus ; some Hoplisoma species, B. difluviatilis , and some specimens of O. aeneus with all or nearly all serrations perpendicularly directed); posterior margin of pectoral-fin spine with most serrations strongly well developed; proximal and/or distal edge of spine variably with less-developed serrations [ Fig. 12B ; see Tencat et al. 2021: 5, fig. 2(c)] (vs. serrations ranging from poorly to well developed in Aspidoras , Brochis , Hoplisoma , and Osteogaster ); and posterior laminar expansion of infraorbital 2 contacting pterotic–extrascapular [ Fig. 9A ; see Tencat et al. 2021: 5, fig. 2(a)] (vs. not contacting pterotic–extrascapular in Aspidoras , except for some specimens of A. lakoi and A. poecilus , most Hoplisoma , and Scleromystao ). See Tencat and Ohara (2016b) and Tencat et al. (2020, 2021, 2024) for further information and illustrations of Corydoras .

Te relationship among Corydoras species studied here is shown in Figure 2 , and Table 1 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Corydoras are shown in Figure 13 .

Genus Aspidoras Ihering, 1907

Aspidoras Ihering, 1907: 30–31 (original description; type species: Aspidoras rochai Ihering, 1907 , by original designation and monotypy). ‒ Nijssen and Isbrücker 1976: 107‒131 (taxonomic review). ‒ Reis 1998: 161 (diagnosis in identification key). ‒ Brito 2003: 144, 146‒147 (phylogeny; diagnosis). ‒Reis, 2003: 291 (listed). ‒Ferraris, 2007: 108 (listed).

Type species: Aspidoras rochai Ihering, 1907 , by original designation and monotypy.

Diagnosis: Aspidoras can be distinguished from the remaining genera in Corydoradinae by having the following features: base of pectoral-fin branched rays with small laminar expansions on its inner margin, generally more evident on first rays; laminar expansions with irregular margins, forming pointed structures, in some specimens ( Fig. 12A ; see Oliveira et al. 2017: 5, fig. 5) (vs. absence of such expansions in remaining genera); two cranial fontanels ( Fig. 14A ; see Tencat et al. 2020: 1075, fig. 4a) (vs. one fontanel in remaining genera, except for Gastrodermus pauciradiatus , Scleromystao lacerdai , and S. virgulatus ); ossified portion of pectoral-fin spine ranging from extremely reduced to moderately developed ( Fig. 12A ; see Tencat et al. 2022a: 31, fig. 14) (vs. ossified portion well developed in remaining genera). See Tencat et al. (2022a) for further information and illustrations on Aspidoras .

Te relationship among Aspidoras species studied here is shown in Figure 3 , and Table 2 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Aspidoras are shown in Figure 15 .

Genus Scleromystax Günther, 1864

Scleromystao Günther, 1864 (type species: Callichthys barbatus Quoy & Gaimard, 1824 , by monotypy; key diagnosis, originally proposed as a subgenus of Callichthys , ranked to genus by Eigenmann & Eigenmann, 1888: 164).

Type species: Callichthys barbatus Quoy & Gaimard, 1824 , by monotypy.

Diagnosis: Scleromystao can be distinguished from the remaining genera in Corydoradinae by having the following combination of features: lateral ethmoid long, its width smaller than its length ( Fig. 16A ), and also bearing a small anterolateral process (vs. lateral ethmoid compact in shape, width greater than or equal to length, and without anterolateral process); palatine slender ( Fig. 16 ; vs. compact, see Brito 2003: fig. 15A); and, except S. salmacis , odontodes inserted in fleshy papillae on preopercular– opercular region of males ( Fig. 17 ; vs. preopercular–opercular region similar in males and females, with only minute, scattered odontodes; Fig. 23D ). In addition, Scleromystao differs from Aspidoras , its sister group, in its reduced ossified portion of the pectoral-fin spine, which is longer than half the length of the first branched pectoral-fin ray (vs. ossified portion up to about half of its length in Aspidoras ; see differences in spine comparing Brito and Reis 2005: fig. 1, holotype of Scleromystao salmacis , dorsal and ventral view, vs. Tencat et al. 2022a: fig. 2, holotype of Aspidoras aldebaran , dorsal and ventral view). Individuals of this genus also possess a conspicuous coloration patern characterized by small striated blotches all over dorsum and sides of head ( Brito et al. 2016: figs 1, 2a, less conspicuous in Scleromystao prionotos ). See Brito and Reis (2005) and Brito et al. (2016) for further information and illustrations on Scleromystao .

Te relationship among Scleromystao species studied here is shown in Figure 4 , and Table 3 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Scleromystao are shown in Figure 18 .

Genus Gastrodermus Cope, 1878

Gastrodermus Cope, 1878: 681 (type species: Corydoras elegans Steindachner, 1877 , by subsequent designation of Gosline, 1940: 10).

Microcorydoras Myers 1953: 270 (described as a subgenus of Corydoras ; type species: Corydoras hastatus Eigenmann & Eigenmann, 1888 , by original designation and monotypy).

Type species: Corydoras elegans Steindachner, 1877 , by subsequent designation of Gosline (1940: 10).

Diagnosis: Gastrodermus can be distinguished from the remaining genera in Corydoradinae by having the following combination of features: mesethmoid conspicuously short (see Brito 2003: 126, fig. 1B) (vs. short to moderate in size in Aspidoras , Hoplisoma , and Osteogaster ; large to extremely large in Corydoras ; moderate to extremely large in Brochis ); posterior margin of dorsal fin spine with serrations mostly directed towards the tip of the spine, variably with some perpendicularly directed serrations ( Fig. 11B ; similar to the illustration by Tencat et al. 2022b: 30, fig. 12B) (vs. most serrations directed towards the origin of the spine in Brochis ; mostly perpendicularly directed serrations in some Hoplisoma ; typically devoid of serrations in Aspidoras and Scleromystao ); posterior margin of pectoral-fin spine with conical serrations mostly directed towards the origin of spine, variably with some serrations perpendicularly directed or directed towards tip of spine ( Fig. 12B ; see Tencat and Pavanelli 2015: 291, fig. 4) (vs. all or nearly all serrations perpendicularly directed in some Hoplisoma species plus B. difluviatilis and some specimens of O. aeneus ; serrations mostly directed towards the tip of the spine in most Hoplisoma and Osteogaster ); and posterior laminar expansion of infraorbital 2 contacting pterotic–extrascapular ( Fig. 9A ; see Bono et al. 2019: 9, fig. 4) (vs. not contacting pterotic–extrascapular in Aspidoras , except for some specimens of A. lakoi and A. poecilus , most Hoplisoma , and Scleromystao ). See Tencat and Pavanelli (2015) and Bono et al. (2019) for further information and illustrations on Gastrodermus .

Te relationship among Gastrodermus species studied here is shown in Figure 5 , and Table 4 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Gastrodermus are shown in Figure 19 .

Genus Osteogaster Cope, 1894

Osteogaster Cope, 1894: 102 (type species: Corydoras eques Steindachner, 1877 , by original designation).

Type species: Corydoras eques Steindachner, 1877 , by original designation.

Diagnosis: Osteogaster can be distinguished from the remaining genera in Corydoradinae by having the following combination of features: mesethmoid ranging from short to moderate in size (see Huysentruyt and Adriaens 2005: 262, fig. 1) (vs. conspicuously short in Gastrodermus ; large in Corydoras ; moderate to extremely large in Brochis ); posterior margin of pectoral-fin spine with all or nearly all serrations directed towards the tip of the spine or perpendicularly directed ( Fig. 11D ; see Tencat et al. 2023: 12, fig. 6B) (vs. mostly directed towards the origin of the spine in Brochis , Corydoras , Gastrodermus , except G. hastatus and G. pygmaeus , and Scleromystao ); posterior laminar expansion of infraorbital 2 contacting pterotic–extrascapular ( Fig. 9A ; see Tencat et al. 2023: 8, fig. 2A) (vs. laminar expansion typically not in contact with pterotic–extrascapular in Aspidoras and Hoplisoma ; not contacting in Scleromystao ); and ground colour of body yellowish orange to reddish orange, with only a single, large dark patch on flanks; all fins devoid of dark spots (see Tencat et al. 2023: 17, fig. 9) (vs. ground colour of body pale yellow, brownish yellow, or greyish yellow, typically with small dark spots at least in some part of the body and/or more than one large, dark patch on body in most species of remaining genera). See Ohara et al. (2016) and Tencat et al. (2023) for further information and illustrations on Osteogaster .

Te relationship among Osteogaster species studied here is shown in Figure 6 , and Table 5 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Osteogaster are shown in Figure 20 .

Genus Brochis Cope, 1871

Brochis Cope, 1871: 112 (type species: Brochis coeruleus Cope, 1872 = Callichthys splendens Castelnau, 1855 , by subsequent designation of Cope, 1872: 278).

Chaenothorao Cope, 1878: 679 (type species: Chaenothorao bicarinatus Cope, 1878 = Callichthys splendens Castelnau, 1855 , by original designation).

Type species: Brochis coeruleus Cope, 1872 = Callichthys splendens Castelnau, 1855 , by subsequent designation of Cope, 1872: 278. Diagnosis: Brochis can be distinguished from the remaining genera in Corydoradinae by having the following features: posterior margin of dorsal-fin spine with laminar serrations mostly directed towards the origin of the spine, except for B. difluviatilis ( Fig. 11A ; see Bentley et al. 2021: 192, fig. 5) (vs. serrations, when present, conical and mostly directed towards the tip of the spine or perpendicularly directed in remaining genera; serrations absent in B. difluviatilis ); posterior margin of pectoral-fin spine with laminar serrations ( Fig. 11C ; see Bentley et al. 2021: 192, fig. 5) (vs. conical in remaining genera); mesethmoid ranging from moderate to extremely large in size, except for B. difluviatilis (see Brito 2003: 126, fig. 1A; and Reis 1998: 177, fig. 8) (vs. conspicuously short in Gastrodermus , and short to moderate in size in Aspidoras , Hoplisoma , and Osteogaster , plus B. difluviatilis ); and posterior laminar expansion of infraorbital 2 contacting pterotic–extrascapular ( Fig. 9A ; see Bentley et al. 2021: 191, fig. 4) (vs. not contacting pterotic–extrascapular in Aspidoras , except for some specimens of A. lakoi and A. poecilus , most Hoplisoma , and Scleromystao ). See Tencat and Ohara (2016a), Tencat et al. (2019), and Bentley et al. (2021) for further information and illustrations on Brochis .

Te relationship among Brochis species studied here is shown in Figure 7 , and Table 6 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Brochis are shown in Figure 21 .

Genus Hoplisoma Swainson, 1838 Hoplisoma Swainson 1838: 336 (type species Cataphractus punctatus Bloch, 1794 , by original designation).

Hoplosoma Agassiz, 1846: 186 (emendation of Hoplisoma Swainson, 1838 ).

Type species: Cataphractus punctatus Bloch, 1794 , by original designation.

Diagnosis: Hoplisoma can be distinguished from the remaining genera in Corydoradinae by having the following combination of features: mesethmoid ranging from short to moderate in size (similar to the illustration by Huysentruyt and Adriaens 2005: 262, fig. 1) (vs. conspicuously short in Gastrodermus ; large in Corydoras ; and large to extremely large in Brochis ); posterior margin of both dorsal- and pectoral-fin spines typically with all or nearly all serrations directed towards the tip of the spine or perpendicularly directed ( Fig. 11B, D ; see Tencat et al. 2022b: fig. 10B, C) (vs. both dorsal and pectoral spines with serrations mostly directed towards the origin of the spine in Brochis , except for B. difluviatilis ; serrations on dorsal spine mostly directed towards tip of spine, with serrations on pectoral spine mostly directed towards origin of spine in Corydoras , Gastrodermus , except for G. hastatus and G. pygmaeus ; dorsal spine typically lacking serrations, with serrations on pectoral spine mostly directed towards origin of spine in Scleromystao ); posterior laminar expansion of infraorbital 2 ranging from strongly reduced to relatively well developed, typically not in contact with pterotic–extrascapular ( Fig. 9B ; see Tencat et al. 2022b: 10, fig. 2A) (vs. well-developed to conspicuously well-developed expansion, contacting pterotic–extrascapular in Brochis , Corydoras , Gastrodermus , and Osteogaster ; infraorbital 2 variably contacting pterotic–extrascapular in A. lakoi and A. poecilus ). See Tencat and Brito (2016), Tencat and Evers (2016), Tencat and Ohara (2016a), Tencat et al. (2016, 2019, 2022b), and Espíndola et al. (2018) for further information and illustrations on Hoplisoma .

Te relationship among Hoplisoma species studied here is shown in Figure 8 , and Table 7 shows the valid species of the genus. Te general morphology and colour patern in life of some representatives of Hoplisoma are shown in Figure 22 .

Identification key to the genera within Corydoradinae

1. Base of pectoral-fin branched rays with small laminar expansions on its inner margin; ossified portion of pectoral-fin spine ranging from extremely reduced to moderately developed, its size up to about half of first pectoral-fin branched ray length ( Fig. 12A ).......................................................................................................................................................................................... Aspidoras

1 ʹ. Base of pectoral-fin branched rays lacking small laminar expansions on its inner margin; ossified portion well developed, its size similar to first pectoral-fin branched ray length ( Fig. 12B ) ............................................................................................................2

2. Posterior margin of dorsal-fin spine typically with most serrations directed towards origin of spine ( Fig. 11A ); serrations variably absent...................................................................................................................................................................................... Brochis

2 ʹ. Posterior margin of dorsal-fin spine typically with most serrations directed towards tip of spine; serrations variably directed perpendicularly or absent ( Fig. 11B )..........................................................................................................................................................3

3. Corner of the mouth, ventral to maxillary barbel, with a roughly triangular fleshy flap, which can be variably elongated, similar to a barbel ( Fig. 10B )........................................................................................................................................................ Corydoras

3 ʹ. Corner of the mouth, ventral to maxillary barbel, lacking a fleshy flap ( Fig. 10A ) ...........................................................................4

4. Snout conspicuously reduced in size; eyes typically positioned on middle portion of lateral surface of head ( Fig. 23A ) ..................................................................................................................................................................................................... Gastrodermus

Figures

Figure 2. Phylogenetic relationship of Corydoras based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements. Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L1 corresponds to a lineage found by Alexandrou et al.(2011). All nodes have bootstrap values of ≥90%.Scale bar represents substitutions per nucleotide site. Te specimen of Corydoras fulleri was photographed alive and not preserved. Photograph by Martin I. Taylor.

Figure 3. Phylogenetic relationship of Aspidoras based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements.Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L2 corresponds to a lineage found by Alexandrou et al.(2011). All nodes have bootstrap values of ≥90%, except the node with the white dot, which has bootstrap of <90%. Scale bar represents substitutions per nucleotide site.Te specimen of Aspidoras poecilus was photographed alive and not preserved. Photograph by Martin I. Taylor.

Figure 4. Phylogenetic relationship of Scleromystao based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements. Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L3 corresponds to a lineage found by Alexandrou et al.(2011). All nodes have bootstrap values of ≥90%.Scale bar represents substitutions per nucleotide site. Te specimen of Scleromystao barbatus was photographed alive and not preserved.Photograph by Martin I. Taylor.

Figure 5. Phylogenetic relationship of Gastrodermus based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements.Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L4 and L5 correspond to lineages found by Alexandrou et al. (2011). All nodes have bootstrap values of ≥90%. Scale bar represents substitutions per nucleotide site. Specimens of Gastrodermus sp. (above) and Gastrodermus hastatus (below) were photographed alive and not preserved. Photographs by Martin I. Taylor.

Figure 6. Phylogenetic relationship of Osteogaster based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements. Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L7 corresponds to a lineage found by Alexandrou et al.(2011). All nodes have bootstrap values of ≥90%.Scale bar represents substitutions per nucleotide site. Te specimen of Osteogaster aff.aenea was photographed alive and not preserved.Photograph by Martin I. Taylor.

Figure 7. Phylogenetic relationship of Brochis based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements. Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers.L8 corresponds to a lineage found by Alexandrou et al.(2011). All nodes have bootstrap values of ≥90%, except the nodes with white dots, which have bootstrap values of <90%.Scale bar represents substitutions per nucleotide site. Te specimen of Brochis cf. splendens was photographed alive and not preserved. Photograph by Martin I. Taylor.

Figure 8. Phylogenetic relationship of Hoplisoma based on a maximum likelihood analysis of the 70% complete matrix of ultraconserved elements. Codes to the right of tip names of putative new species represent museum catalogue numbers and voucher specimen numbers. L6 and L9 correspond to lineages found by Alexandrou et al. (2011). All nodes have bootstrap values of ≥90%, except the nodes with white dots, which have bootstrap values of <90%.Scale bar represents substitutions per nucleotide site. Te specimen of Hoplisoma weitzmani was photographed alive and not preserved. Photograph by Martin I. Taylor.

Figure 9. Lateral view of the head of cleared and stained specimens, as follows: A, Corydoras aurofenatus (NUP 16191, non-type specimen); B, Aspidoras belenos (UFRJ 4419, paratype); and C, Hoplisoma granti (NUP 20985, paratype), showing general osteological patern in lateral view. Abbreviations:io1, infraorbital 1; io2, infraorbital 2; pes, pterotic–extrascapular; sph, sphenotic. Additional pore of temporal sensory canal at sphenotic is outlined in yellow in A. Scale bars:1.0 mm.

Figure 10. Detail of the tip of snout of: A, Corydoras sp. CW83 (CITL 929, 45.3 mm standard length); and B, a paratype of Corydoras octocirrus (IRSNB 471, 49.2 mm standard length), showing the area at the corner of the mouth in lateral view. Te yellow arrowhead in A indicates the triangular fleshy flap (bordered by a white doted line). Te yellow arrowhead in B indicates the elongated, barbel-like structure (bordered by a white doted line) located between the maxillary barbel and anteroventral portion of snout tip. Scale bars:1 mm.

Figure 11. Lateral view of the dorsal-fin spine and dorsal view of the pectoral-fin spine in a cleared and stained non-type specimen of Brochis arcuata (ZUFMS 5724; A and C, respectively) and in a cleared and stained paratype of Hoplisoma granti (NUP 20985; B and D, respectively), showing the different serration paterns on their respective posterior margins.Scale bars: 1.0 mm.

Figure 12. Pectoral fin of cleared and stained specimens in dorsal view of: A, Aspidoras kiriri (NUP 18246, paratype), showing the laminar expansions on base of branched rays (black arrows); and B, Corydoras fulleri (ZUFMS 6487, paratype), which lacks these laminar expansions. Te black lines represent scale bars. Abbreviation: pfs, pectoral-fin spine. Scale bars: 1.0 mm.

Figure 13. Uncatalogued aquarium specimens of the following: A, Corydoras geoffroy; B, Corydoras cf. semiaquilus; C, Corydoras cf.pastazensis; and D, Corydoras cf. vitatus, showing their general morphology and colour patern in life. Photograph A by Daniel Konn-Veterlein and B–D by Hans Evers.

Figure 14. Dorsal view of the head of cleared and stained specimens of: A, Aspidoras albater (MZUSP 40793, non-type specimen); and B, Osteogaster maclurei (CITL 430, paratype), showing the presence of two and one cranial fontanels (yellow arrowheads), respectively. Abbreviations:f, frontal; n, nasal; pes, pterotic-extrascapular; pso, parieto-supraoccipital; sph, sphenotic. Scale bars: 1 mm.

Figure 15. Uncatalogued aquarium specimens of: A, Aspidoras albater; B, Aspidoras aldebaran; C, Aspidoras psammatides; and D, Aspidoras velites, showing their general morphology and colour patern in life.Photographs A, B, and D by Hans Evers and C by Marcelo Melo.

Figure 16. General morphology of anterior region of neurocranium in dorsal view (A) with the detail of the palatine in lateral view (B) of Scleromystao lacerdai (MNRJ 26017). Right nasal capsule bones partially deleted. Abbreviations: f, frontal; le, lateral ethmoid; me, mesethmoid; n, nasal; pal, palatine. Scale bar: 1 mm.

Figure 17. Lateral view of the head of Scleromystao barbatus (MNRJ 43363), showing the typical patch of odontodes (outlined by white doted line) presented by male individuals.Scale bar: 1 mm.

Figure 18. Uncatalogued aquarium specimens of: A, Scleromystao sp. CW38; B, Scleromystao prionotos; and C, a pair of Scleromystao barbatus, with the female on the lef and the male on the right, showing their general morphology and colour patern in life. Photographs by Hans Evers.

Figure 19. Uncatalogued aquarium specimens of:A, Gastrodermus sp. CW8; B, Gastrodermus guapore; C, Gastrodermus pygmaeus; and D, Gastrodermus sp., displaying their general morphology and colour paterns in life.Photograph A courtesy of Daniel Konn-Veterlein and B–D courtesy of Hans Evers.

Figure 20. Uncatalogued aquarium specimens of:A, Osteogaster aenea; B, Osteogaster sp. CW10; C, Osteogaster eques; and D, Osteogaster maclurei, showing their general morphology and colour patern in life.Photographs by Hans Evers.

Figure 21. Uncatalogued aquarium specimens of: A, Brochis robusta; B, Brochis sp. CW35; C, Brochis arcuata; and D, Brochis reticulata, showing their general morphology and colour patern in life.Photographs by Hans Evers.

Figure 22. Uncatalogued aquarium specimens of: A, Hoplisoma punctatum; B, Hoplisoma eversi; C, Hoplisoma weitzmani; and D, Hoplisoma concolor, showing their general morphology and colour patern in life. Photographs by Hans Evers.

Figure 23. Uncatalogued aquarium specimens illustrating the general snout morphology within Corydoradinae, showing: A, the conspicuously short snout in Gastrodermus guapore; B, the short snout in Osteogaster eques; C, the moderate-sized and straight snout in Brochis lamberti; D, the long and straight snout in Scleromystao barbatus; E, the long and concave snout in Corydoras cf. vitatus; and F, the extremely long and concave snout in Brochis multiradiata. Photographs by Hans Evers.