taxonID	type	description	language	source
03A16507FFBC384F5764FCA2DC3743BF.taxon	description	(Fig. 2 – 8) Zoobank: urn: lsid: zoobank. org: act: 174 DC 621 - 15 A 2 - 41 DE-AC 97 - EF 20266 B 2257 Typematerial. Holotype: adult male, (body length [L] 10.29 mm; head length [HL] 0.69 mm), MZUSP 45191, Brazil, state of São Paulo, municipality of R ibeirão Grande, Parque Estadual Intervales (24 ° 16 ’ 18.42 ” S 048 ° 25 ’ 29.3 ” W), March 2000, P. C. Bispo coll. — Paratypes: 1 adult female (L 9.8 mm; HL 0.50 mm), MZUSP 45192; 31 whole individuals and 3 males and females on slides CCUFLA 453 (same collection data as the holotype); 1 male on slides, CCUFLA 454; Brazil, state of São Paulo state, municipality of Iporanga, Parque Estadual Intervales, Gruta do Minotauro cave entrance (24 ° 16 ’ 34.7 ” S 48 ° 27 ’ 22.7 ” W), October 2009, M. E. Bichuette; T. L. C. Scatolini; A. Pereira and D. Monteiro-Neto colls. Diagnosis. Body surface smooth. Eyes round, pigmented. Epimeron 1 and 3 postero-distal margin acute (acute angle). Antenna 2 not half the body length. Maxilla 1 palp longer than wide, reaching almost half of distance between base of palp and base of setae on outer plate. Gnathopod 1 propodus inner face with 10 serrate setae, anterior and posterior margins with comb-scales. Pleopods with 2 coupling spines and several setules present on margins. Uropod 3 shorter than telson, peduncle longer than ramus, with 6 cuspidate setae with accessory seta and ramus with distal cuspidate seta with accessory seta and some simple setae. Telson with 2 to 4 apical simple and symmetrical setae, with 3 simple setae on both sides, laterally. Coxal gills sac-like and present on segments 2 to 6. Sternal gills present on segments 3 to 7. Description of male (Fig. 2 A). Mean body length: 8.7 ± 1.3 mm (N = 7); mean head length: 0.68 mm ± 0.16 mm (N = 7). Body surface smooth. Epimeral plates 2 – 3 accuminate (Fig. 4 B). Coxae 1 – 4 subequal in size and shape, slightly overlapping. Coxa 1 similar to 2 and 3. Coxa 4 longer than wide, excavated posteriorly. Coxa 5 posterior lobe narrower than anterior lobe. Coxa 6 and 7 longer than wide. Eyes round and pigmented. Antenna 1 (Fig. 3 A) about 3.8 × smaller than body length, 1.4 × smaller than antenna 2, 1.6 × longer than peduncle of antenna 2; peduncle 1.4 × longer than head; article 1 1.2 × longer than 2, article 3 1.1 × shorter than 1 and 1 × shorter than article 2; flagellum with 14 articles, 1.7 × longer than peduncle; aesthetascs (Fig. 3 A, highlighted) occurring on flagellum from article 3 distally. Antenna 2 (Fig. 3 B) 2.6 × smaller than body length; peduncle slender, 2.2 × longer than head; article 4 with similar size than article 5; flagellum with 17 articles, 1.4 × longer than peduncle. Mandiblewithoutpalp; incisortoothed; left (Fig. 3 C) mandible with 5 teeth and setal row with 5 pappose setae and some setules on apical margin, lacinia mobilis with 3 teeth, molar process with accessory seta; right mandible (Fig. 3 D) with abundant setules on apical margin, setal row with 3 pappose setae; broad and cylindrical molar process with accessory seta. Upper lip (Fig. 3 E) margin rounded; distal border covered by setules on ventral and dorsal face. Lower lip (Fig. 3 F) outer lobes rounded and distally notched, with several setules on dorsal and ventral face. Maxilla 1 (Fig. 3 G) inner plate slender, with 2 pappose setae and several setules distally. Outer plate with 9 papposerrate setae apically. Palp short, uniarticulate, longer than wide, reaching almost half of distance between base of palp and base of seta on outer plate, with distal short seta and some setules on margin. Maxilla 2 (Fig. 3 H) inner plate subequal to outer plate, inner plate with 1 papposerrate seta, 6 pappose setae and several simple distal setae; outer plate with 3 pappose setae and several simple distal setae; inner and outer plates covered by several setules. Maxilliped (Fig. 4 A) inner plate with 3 cuspidate distal setae and several pappose setae, without comb-scales; outer plate 1.4 × smaller than inner plate, with several simple setae, without comb-scales; palp longer than outer plate and subequal to inner plate, with 4 articles, covered with several simple long setae on the inner margin; article 1 outer margin with few simple setae; article 2 outer margin with few long simple setae; article 3 outer margin with few long pappose setae, without comb-scales; article 4 (dactylus) unguiform, 2.2 × shorter than third article, with some pappose setae, shorter than nail, without comb-scales, and distal nail present. Variation: one specimen was also found with 7 cuspidate distal setae and several pappose setae on inner plate; outer plate with several simple and few pappose setae; article 2 of palp with some serrate setae apically on outer margin; article 4 (dactylus) with serrate setae instead of pappose. Gnathopod 1 (Fig. 5 A) subchelate; coxal plate 1.8 × wider than longer, with several short simple setae on margin; basis and ischium with dorsal and apical serrate setae and comb-scales on posterior margin of ischium; merus with some pappose setae on distal margin and polygonal pattern present; carpus 1.8 × longer than wide, 1.3 × longer than propodus, with lateral distal lobe produced, with 5 serrate setae, without comb-scales; posterior lobe, with polygonal pattern and pectinate border expressed, without comb-scales and with several serrate setae on margin and 4 pappose setae on inner face; propodus 1.4 × longer than wide, hammer-shaped, with several simple long setae on disto-anterior margin and polygonal pattern present, inner face with 10 serrate setae, with few simple setae and comb-scales absent; palm slope transverse, with row of many simple setae, posterior distal corner with 1 long and strong cuspidate seta with accessory seta, polygonal pattern present, and comb-scales absent; dactylus claw-like, polygonal pattern present on disto-anterior margin, terminal simple setae and polygonal pattern present on proximal margin, with 1 plumose seta dorsally. Gnathopod 2 (Fig. 5 B) subchelate; coxal plate 1.8 × wider than long, with simple setae on margin; basis and ischium with several serrate setae and polygonal pattern on posterior margin of ischium; merus with few serrate setae on posterior margin and polygonal pattern; carpus 3.6 × wider than long, posterior lobe slim produced between merus and propodus, forming scoop-like structure, margin with several pappose setae, polygonal pattern, pectinate border and serrate setae on lateral distal lobe, without comb-scales; propodus ovate, 1.4 × longer than wide, comb-scales absent; palm shorter than posterior margin of propodus, slope transverse, margin with 1 row of several cuspidate setae with accessory seta and simple setae, posterior distal corner with 2 long and strong cuspidate setae and with cup for dactylus, polygonal pattern present; dactylus claw-like, congruent with palm, plumose seta dorsally, and terminal simple setae and polygonal pattern present on the proximal and disto-anterior margin. Pereopods 3 to 7 (Fig. 6 A – E) simple. Pereopods 3 and 4 merus and carpus posterior margin with several serrate and simple setae and some simple with accessory seta in carpus; propodus posterior margin of pereopod 3 and 4 with some simple setae and several cuspidate with accessory seta; dactylus 3.6 × and 4.1 × shorter than propodus, respectively, with plumose seta dorsally. Pereopods 5 to 7 merus, carpus and propodus posterior margin with several cuspidate setae some of them with accessory seta and few simple setae, dactylus 4.0 ×, 3.9 ×, and 4.3 × shorter than propodus, respectively, with plumose seta dorsally. Pereopod 3 and pereopod 5 similar in size; pereopod 4 smaller than others; pereopod 6 longer than pereopod 7. Pleopods (Fig. 7 A) peduncle 3.3 × longer than wide, 1.7 × mean size of rami, with 2 coupling spines and several setules present on margins; both rami with several plumose setae. Uropod 1 (Fig. 7 B) peduncle 3.1 × longer than outer ramus and subequal to inner ramus, with 4 cuspidate setae with accessory seta and 1 simple seta; inner ramus slightly longer than outer ramus, with 3 dorsal cuspidate setae with accessory seta on margin and 7 cuspidate setae with accessory seta apically, without curved seta; outer ramus with 5 dorsal cuspidate setae with accessory seta on the margin and 3 cuspidate setae with accessory seta apically. Uropod 2 (Fig. 7 C) 1.4 × shorter than uropod 1, peduncle longer than inner ramus, with 4 cuspidate setae with accessory seta; inner ramus with 4 dorsal cuspidate setae and 6 cuspidate setae apically, all with accessory seta; outer ramus with 4 dorsal cuspidate setae and 4 apical cuspidate setae, all with accessory seta. Uropod 3 (Fig. 7 D) 0.7 × shorter than peduncle of uropod 1 and 0.6 × than peduncle of uropod 2; 1.1 × shorter than telson; peduncle with 6 cuspidate setae with accessory seta; inner ramus absent; outer ramus uniarticulate, subequal to peduncle, with one cuspidate with accessory seta and some simple setae. Telson (Fig. 7 E) entire, 1.1 × longer than wide, apically rounded, with 2 to 4 apical simple setae, symmetrically, with 3 simple setae laterally on both sides. Variations: 3 plumose setae laterally on each side. Epimeron (Fig. 4 B) 2 and 3 postero-distal margin acute. Coxal gills sac-like and present on pereonites 2 to 7. Sternal gills tubular and present on pereonites 3 to 7. Description of female. (Fig. 2 A) Mean body length: 8.3 ± 1.1 mm (N = 7); mean head length: 0.68 ± 0.07 mm (N = 7). Gnathopod 1 (Fig. 8 A) similar to male gnathopod 1 in size and shape; ischium with polygonal pattern; carpus 2.2 longer than wide, without polygonal pattern and comb-scales, with pectinate border and some serrate and simple setae; propodus 1.7 × longer than wide, disto-anterior margin with few simple setae and polygonal pattern present, inner face with 10 serrate setae; palm transverse with several long simple setae, posterior distal corner with 2 long and strong cuspidate setae with accessory seta, without comb-scales and polygonal pattern; dactylus claw-like, with polygonal pattern on disto-anterior margin, with 1 plumose seta dorsally and terminal simple setae on proximal margin. Gnathopod 2 (Fig. 8 B) similar in size and shape to gnathopod 1; ischium and merus with comb scales; carpus 2.3 × longer than wide, without comb-scales, posterior lobe produced and forming scoop-like structure, without pectinate margin and polygonal pattern, with several serrate setae and 2 long serrate setae on inner face; propodus 2.3 × longer than wide, hammer-shaped, inner face with some pappose setae; palm 1.1 × shorter than posterior margin of propodus, without polygonal pattern, inner margin with few simple setae, palm slope transverse, posterior distal corner with 2 long and strong cuspidate seta with accessory seta and comb-scales present; dactylus claw-like, with comb-scales on disto-anterior margin, with 1 plumose seta dorsally and terminal simple setae on proximal margin. Telson (Fig. 8 C) 1.1 × longer than wide, similar in shape to male, with 2 to 4 simple apical setae and 1 to 3 plumose setae on each side of margin. Etymology. The epithet bocaina is a recognition of the river where the two populations of this new species are found. Habitat. Freshwater, troglophilic. The species is categorized as troglophilic because it has wellestablished subterranean and epigean (surface) populations. They are sometimes also called facultative cave-dwellers. Specimens of H. bocaina sp. nov. were collected at two different sites, including the rapids of the Roda d’Água tourist route and at the cave entrance zone of the Gruta do Minotauro. The surrounding forest is well preserved. The rapids of PEI present an irregular flow, allowing their interaction with the substrate and, thus, the formation of microcurrents with different speeds. In addition, from this interaction, microhabitats are formed between the rocks, allowing the accumulation of sand and leaves (de Paula Paciência, 2011). Remarks. Among all Hyalella species that occur in Brazil, H. bocaina sp. nov. is distinguished from the other 26 species by the absence of a curved seta on the inner ramus of uropod 1 of the male. Table 1 presents the main morphological differences between H. bocaina sp. nov. and the other Hyalella species from Brazil. We highlight that H. bocaina sp. nov., differs from H. caeca, H. spelaea and Hyalella troglofugia Bastos-Pereira, Oliveira and Ferreira, 2018, for being epigean, with no evident troglomorphic features; also, H. bocaina sp. nov. presents a pectinate border expressed on the carpus of the female and male gnathopod 1, which is different from Hyalella montana Rodrigues, Senna, Quadra and Bueno, 2017; there are no flanges — or dorsal carina — in the new species, different from Hyalella pseudoazteca González and Watling, 2003 b; and H. bocaina sp. nov. has antenna 2 shorter than half the body length, which is different from Hyalella longipropodus Limberger, Graichen and Castiglioni, 2021.	en	Bichuette, Alessandra Angélica de Pádua Bueno Carolina Mendes Deotti Ludmila Rocha Penoni Maria Elina (2025): Expanding the knowledge of Hyalella Smith, 1874 (Amphipoda: Hyalellidae) for southeast Brazil: two new troglophilic species from caves of the Atlantic Rainforest. Nauplius (e 20250478) 33: 1-27, DOI: 10.1590/2358-2936e20250478, URL: https://doi.org/10.1590/2358-2936e20250478
03A16507FFB4385355E8FD99DC2D447A.taxon	description	(Fig. 9 – 15) Zoobank: urn: lsid: zoobank. org: act: B 4 E 06617 - 3 FC 0 - 4 A 94 - B 3 C 5 - 63 DB 735 B 2 AB 3 Type material. Holotype: adult male (Fig. 9 A) (L 10.62 mm, HL 1.01 mm), MZUSP 45193, Brazil, state of São Paulo, municipality of Apiaí, Parque Estadual Turístico do Alto Ribeira, Temimina II cave (24 ° 22 ’ 36.8 ” S 48 ° 33 ’ 56.2 ” W), November 2017, M. E. Bichuette, T. L. C. Scatolini, A. Pereira, D. Monteiro-Neto colls. — Paratypes: 1 adult female (Fig. 9 B) (L 6.44 mm; HL 0.49 mm), MZUSP 45190, same locality as the holotype, April 2018, M. E. Bichuette, T. L. C. Scatolini, A. Pereira, D. Monteiro-Neto colls.; 1 male on slide CCUFLA 451, and 1 female on slide CCUFLA 452, same locality as the holotype, March 2009, M. E. Bichuette, T. L. C. Scatolini, A. Pereira, D. Monteiro-Neto colls. Diagnosis. Body surface smooth. Eyes round, pigmented. Epimeron 1 and 3 postero-distal margin subacute (angular and slightly rounded), epimeron 2 postero-distal margin acute (acute angle). Antenna 2 smaller than body length. Maxilla 1 palp longer than wide, longer than half distance between base of palp and base of seta on outer plate. Gnathopod 1 propodus posterior margins without comb-scales. Uropod 3 ramus longer than peduncle, with excavation close to apex, bearing cuspidate seta with accessory seta, simple seta, and short triangular cuspidate seta apically. Telson with 8 apical cuspidate setae with accessory seta and 3 small plumose setae on each side, Deotti et al. Deotti et al.: New Hyalella Nauplius, 33: e 20250478 Deotti et al. Deotti et al.: New Hyalella Nauplius, 33: e 20250478 Deotti et al. Deotti et al.: New Hyalella Nauplius, 33: e 20250478 Nauplius, 33: e 20250478 laterally. Coxal gills sac-like and present on segments 2 to 6. Sternal gills present on segments 3 to 7. Description of male (Fig. 9 A). Mean body length: 10.77 mm (N = 2); mean head length: 0.96 mm (N = 2). There were smaller animals observed at the collection site. Body surface smooth. Epimeral plates 2 acute and 1 and 3 subacute (Fig. 7 J). Coxae 1 – 4 subequal in size and shape, slightly overlapping. Coxa 1 similar to 2 and 3. Coxa 3 wider than 4. Coxa 4 longer than wide, excavated posteriorly. Coxa 5 posterior lobe narrower than anterior lobe. Coxa 6 as long as wide. Coxa 7 reduced. Eyes round and pigmented. Antenna 1 (Fig. 10 A) about 3.2 × smaller than body length, 1.5 × smaller than antenna 2, 1.7 × longer than peduncle of antenna 2; peduncle 1.2 × longer than head; article 1 1.3 × longer than 2, article 3 1.3 × shorter than 1 and 1 x shorter than article 2; flagellum with 20 articles, 2.5 × longer than peduncle; aesthetascs occurring on flagellum from article 7 to 19 distally. Antenna 2 (Fig. 10 B) 2.2 × smaller than body length; peduncle slender, 2.1 × longer than head; article 4 1.2 × shorter than article 5; flagellum with 23 articles, 1.5 × longer than peduncle. Mandible without palp; incisor toothed; left (Fig. 10 C) lacinia mobilis with 5 teeth and setal row with 3 long and strong pappose setae and 1 shorter pappose seta, molar process without accessory seta; right mandible (Figure 10 D) with 2 longer central and 2 shorter pappose setae; molar process broad and cylindrical without accessory seta. Upper lip (Fig. 10 E) margin rounded; distal border covered by setules. Lower lip (Figure 4 F) outer lobes rounded and distally notched, with setules on dorsal and ventral faces. Maxilla 1 (Fig. 10 G) inner plate slender, shorter than outer plate, with 2 apical papposerrate setae and setules distally. Outer plate with 9 serrate setae, increasing in size from inner to outer margin. Palp relatively long, uniarticulate, longer than wide, reaching more than half of distance between base of palp and base of seta on outer plate, with distal long seta. Maxilla 2 (Fig. 10 H) inner plate subequal to outer plate, inner plate with 1 proximal and 1 distal strong papposerrate seta; inner and outer plates with several serrulate and simple setae, and setules distally. Maxilliped (Fig. 11 A) inner plate longer than wide, with 3 cuspidate distal setae and up to 8 small pappose setae apically, without comb-scales; outer plate smaller than inner plate, with several long simple setae, without comb-scales; palp longer than inner, longer than outer plate, with 4 articles; article 1 triangular, outer margin with up to 3 long simple setae; article 2 longer than wide, inner margin with several long simple setae, outer margin with up to 6 long simple setae and 1 long and strong pappose seta; article 3 longer than wide, inner margin with several long simple setae, outer margin with pappose and long simple setae, without comb-scales; dactylus unguiform, relatively small, longer than wide, with distal setae simple and shorter than nail, without comb-scales, and distal nail present. Gnathopod 1 (Fig. 12 A) subchelate; coxal plate 1.6 × wider than longer, with simple setae on margin; basis and ischium with dorsal and apical serrate setae, without comb-scales; merus with pappose setae on distal margin, without comb-scales; carpus 2.6 × longer than wide, 1.1 × longer than propodus, with lateral distal lobe produced, with 8 serrate seta on disto-anterior margin, without comb-scales; posterior lobe without pectinate border or polygonal pattern, several pappose setae on margin and in inner face; propodus 1.4 × longer than wide, hammer-shaped, with several simple long setae on disto-anterior margin, comb-scales absent, inner face with many pappose setae, disto-posterior margin with simple setae and polygonal pattern; palm slope transverse, with many pappose setae with accessory seta, posterior distal corner with 2 long and strong cuspidate setae with accessory seta and polygonal pattern; dactylus claw-like, polygonal pattern present on disto-anterior margin, with 1 plumose seta dorsally and terminal simple setae on proximal margin. Gnathopod 2 (Fig. 12 B) subchelate; coxal plate 1.7 × wider than long, with simple setae on margin; basis and ischium with several distal and apical serrate setae, without comb-scales; merus with up to 12 papposerrate setae on posterior margin, without comb-scales; carpus 2.6 × wider than long, posterior lobe slim produced between merus and propodus, forming scoop-like structure, margin with many papposerrate setae, polygonal pattern forming pectinate border; propodus ovate, 1.2 × longer than wide, polygonal pattern present and few small pappose setae on inner face; palm subequal to posterior margin of propodus, slope oblique, margin with row of several cuspidate setae with accessory seta and few simple and pappose setae, posterior distal corner with 2 short cuspidate setae and with cup for dactylus; dactylus claw-like, congruent with palm, plumose seta dorsally, terminal simple setae on proximal margin and comb-scales absent. Pereopods 3 to 7 (Fig. 13 A – E) simple. Pereopods 3 and 4 merus and carpus posterior margin with several simple setae, some cuspidate with accessory seta and some serrate setae; propodus posterior margin of pereopod 3 and 4 with several cuspidate setae with accessory seta, some simple setae and few serrate setae; dactylus 2.7 × and 2.8 × shorter than propodus, respectively, with plumose seta dorsally. Pereopods 5 to 7 merus, carpus and propodus posterior margin with several cuspidate setae most of them with accessory seta and some simple setae, dactylus 2.5 ×, 3.1 ×, and 2.8 × shorter than propodus, respectively, with plumose seta dorsally. Pereopod 3 and pereopod 4 similar sizes; pereopod 5 smaller than others; pereopod 6 longer than pereopod 7. Pleopods (Fig. 14 A) peduncle longer than wide, shorter than both rami, with 2 coupling spines; both rami with several plumose setae. Uropod 1 (Fig. 14 B) 1.4 × longer than uropod 2; peduncle 1.1 × longer than outer ramus and subequal to inner ramus, with 5 cuspidate setae with accessory seta; inner ramus 1.2 × longer than outer ramus, with 3 dorsal cuspidate setae with accessory seta on margin and 3 small cuspidate setae with accessory seta, 2 longer cuspidate and 1 short triangular cuspidate seta apically, without curved seta; outer ramus with 3 dorsal cuspidate setae with accessory seta on margin and 2 longer, 1 shorter and 1 triangular cuspidate setae apically. Uropod 2 (Fig. 14 C) peduncle subequal to outer ramus and 0.83 × size of inner ramus, with 4 cuspidate setae; inner ramus with 3 dorsal cuspidate setae with accessory seta and 5 cuspidate setae apically, only 1 with accessory seta; outer ramus with 4 dorsal cuspidate setae, sequentially increasing in size, and 2 short and 2 longer apical cuspidate setae. Uropod 3 (Fig. 14 D) 0.8 – 0.9 × shorter than peduncle of uropod 2; peduncle longer than wide, with 4 cuspidate setae with accessory seta; inner ramus absent; outer ramus uniarticulate, 1.2 × longer than peduncle, with excavation close to apex, bearing 1 cuspidate seta with accessory seta and 1 simple seta, and 2 long, 2 short simple setae, 1 long cuspidate seta with accessory seta and 1 short triangular cuspidate seta apically. Telson (Fig. 14 E) entire, 1.2 × longer than wide, apically rounded, with up to 8, almost symmetrical, small cuspidate setae with accessory seta apically, with 3 small plumose setae on each side, laterally. Epimeron (Fig. 11 B) 1 and 3 subacute; epimeron 2 acute. Coxal gills sac-like and present on pereonites 2 to 6. Sternal gills tubular, present on pereonites 3 to 7. Description of female (Fig. 9 B). Mean body length: 10.24 mm (N = 3); mean head length: 0.73 mm (N = 3). Gnathopod 1 (Fig. 15 A) similar to male gnathopod 1; carpus 1.4 × longer than wide, without comb-scales, posterior lobe with pectinate margin, with several serrate setae; propodus 1.5 × longer than wide, hammer-shaped, with comb-scales, palm 0.7 × size of posterior margin of propodus, without comb-scales, inner margin with 11 papposerrate setae, palm slope transverse, dactylus claw-like, with comb-scales. Gnathopod 2 (Fig. 15 B) similar in size and shape to gnathopod 1; carpus similar to gnathopod 1; propodus 1.4 × longer than wide, with polygonal pattern on disto-posterior margin, inner margin with up to 9 papposerrate setae, palm transverse with several long simple setae, without comb-scales; dactylus claw-like, congruent to palm, with 1 plumose seta apically and polygonal pattern on posterior margin. Telson (Fig. 15 C) 1.2 × longer than wide, similar in shape to male’s, with up to 9 cuspidate setae with accessory seta asymmetrically distributed apically, and 2 small plumose setae on each side, laterally. Etymology. The epithet temimina is a recognition of the cave, Temimina II, where the specimens of this new species were collected. Habitat. Freshwater, hypogean, typical lentic waters, with bottom formed by silt and pebbles. Specimens of Hyalella temimina sp. nov. were found only at cave Teminina II. Despite the absence of specimens in the surface streams, Hyalella temimina sp. nov. does not show troglomorphic traits, and we hypothesize that the new species is troglophilic, similar to Hyalella bocaina sp. nov. Remarks. Table 1 presents the main morphological features that H. temimina sp. nov. differs from the other 42 species that occur in Brazil. It is a hypogean species with no signs of troglomorphism, having large and pigmented eyes. In this way, it differs from classically troglomorphic species, such as H. caeca, H. spelaea, and H. troglofugia. Hyalella temimina sp. nov. body is smooth, which is different from H. pseudoazteca; H. temimina sp. nov. has pappose setae and does not have comb-scales on the propodus of male gnathopod 1, while H. longipropodus has serrate setae on the inner face of the propodus and comb scales on propodus of male ganthopod 1. Moreover, H. temimina sp. nov. is characterized by the presence of pappose setae on the inner surface of the propodus of gnathopod 1, which differentiates the new species from H. bala, H. dielaii, and H. montana. Finally, H. temimina sp. nov. is different from Hyalella bocaina sp. nov. because the former has only two teeth on the right mandible incisor, palp of maxilla 1 relatively longer, male gnathopod 1 with polygonal pattern only on the propodus and dactylus, gnathopod 2 with polygonal pattern only on the propodus, and uropod 3 with an apical excavation on the ramus, whereas H. bocaina sp. nov. has six teeth on the right mandible incisor, relatively shorter palp of maxilla 1, and polygonal pattern on the merus and ischium of both male gnathopods, with no excavations on the uropod 3 ramus. Conservation. We propose for both species, H. bocaina sp. nov. and H. temimina sp. nov., the categorization as vulnerable. Vulnerable (VU) - (D 2) = typically, area of occupancy (AOO <20 km 2) or number of locations (≤ 5) (ICMBio, 2013). Their populations are restricted to small areas and, similar to other Hyalella species, they are possibly endemic and restricted to the sites, or even micro-basins, where they were collected.	en	Bichuette, Alessandra Angélica de Pádua Bueno Carolina Mendes Deotti Ludmila Rocha Penoni Maria Elina (2025): Expanding the knowledge of Hyalella Smith, 1874 (Amphipoda: Hyalellidae) for southeast Brazil: two new troglophilic species from caves of the Atlantic Rainforest. Nauplius (e 20250478) 33: 1-27, DOI: 10.1590/2358-2936e20250478, URL: https://doi.org/10.1590/2358-2936e20250478
