Corresponding author: Fábio F. Roxo (
Academic editor: N. Bogutskaya
Two new species of
Roxo FF, Zawadzki CH, Troy WP (2014) Description of two new species of
The genus
All measurements and counts were taken from the left side of the fish. Measurements were made from point to point to the nearest 0.1 mm with a digital caliper. Body plate and osteology nomenclature follows
Morphometrics and meristics of
Holotype | Range | Mean | SD | Holotype | Range | Mean | SD | |
---|---|---|---|---|---|---|---|---|
SL | 26.4 | 22.8−28.4 | 24.4 | 1.43 | 26.2 | 18.0−26.2 | 22.7 | 2.99 |
|
||||||||
Head length | 36.5 | 35.6−41.1 | 37.7 | 1.41 | 39.2 | 36.1−41.7 | 39.4 | 1.44 |
Predorsal length | 46.8 | 45.3−52.1 | 48.3 | 1.51 | 47.9 | 46.9−51.8 | 49.0 | 1.54 |
Dorsal-fin spine length | 22.4 | 22.4−28.3 | 24.5 | 1.62 | 25.4 | 25.2−27.0 | 26.2 | 0.50 |
Anal-fin unbranched ray length | 18.7 | 16.3−21.3 | 19.2 | 1.34 | 18.2 | 17.4−21.4 | 19.8 | 0.87 |
Pectoral-fin spine length | 23.6 | 21.6−27.6 | 24.7 | 1.57 | 27.5 | 27.0−30.1 | 28.2 | 0.53 |
Pelvic-fin unbranched ray length | 18.4 | 16.8−23.2 | 20.6 | 1.45 | 18.7 | 18.0−21.1 | 19.7 | 0.98 |
Cleithral width | 24.6 | 23.8−26.8 | 25.3 | 0.89 | 23.5 | 22.2−24.3 | 23.3 | 0.49 |
Thoracic length | 18.4 | 17.6−21.6 | 19.0 | 0.80 | 18.8 | 16.1−19.8 | 17.8 | 1.12 |
Abdominal length | 21.9 | 17.9−22.3 | 20.5 | 1.24 | 21.5 | 16.2−21.6 | 19.0 | 1.82 |
Body depth at dorsal-fin origin | 21.1 | 18.6−23.9 | 21.6 | 1.25 | 18.8 | 16.9−20.7 | 18.1 | 1.30 |
Caudal-peduncle length | 28.3 | 26.3−31.5 | 29.3 | 1.18 | 27.5 | 25.3−29.8 | 27.7 | 1.61 |
Caudal-peduncle depth | 10.5 | 10.8−12.5 | 11.4 | 0.64 | 10.6 | 10.2−11.3 | 10.7 | 0.27 |
|
||||||||
Snout length | 50.7 | 46.9−52.2 | 49.6 | 1.49 | 51.5 | 50.7−57.1 | 53.7 | 1.50 |
Orbital diameter | 15.9 | 13.9−17.6 | 15.6 | 0.93 | 12.8 | 11.0−14.1 | 12.5 | 0.88 |
Interorbital width | 35.2 | 32.1−37.1 | 34.9 | 1.52 | 32.8 | 32.4−36.0 | 34.2 | 1.21 |
Head depth | 54.7 | 51.6−59.2 | 55.4 | 2.17 | 45.3 | 42.4−47.7 | 44.8 | 1.99 |
Suborbital depth | 24.7 | 20.9−25.5 | 24.1 | 1.26 | 20.8 | 17.4−22.0 | 20.0 | 0.85 |
Mandibular ramus | 11.2 | 6.8−12.9 | 10.7 | 1.12 | 6.0 | 6.0−8.0 | 6.8 | 0.57 |
|
|
|
|
|
|
|
|
|
Left premaxillary teeth | 13 | 11−18 | 14 | 2.0 | 10 | 6−10 | 8 | 1.37 |
Left dentary teeth | 14 | 11−15 | 13 | 1.22 | 6 | 4−7 | 6 | 0.42 |
Left lateral scutes | 24 | 24−25 | 24 | 0.64 | 24 | 24−25 | 24 | 0.48 |
MZUSP 115061, 26.4 mm SL, female, Brazil, Paraná State, boundary between municipalities of Cambira and Apucarana, ribeirão Cambira, affluent of rio Ivaí, upper rio Paraná basin,
All from Brazil, Paraná State. DZSJRP 18244, 3 males, 26.3−26.8 mm SL, ribeirão Salto Grande, rio Ivaí basin, municipality of Maria Helena,
Variation in hypertrophied series of anterolateral (
Morphometric data presented in
Head rounded in dorsal view, snout round to slightly pointed. Dorsal and ventral series of odontodes along anterior margin of snout completely covering its tip; odontodes larger than remaining ones on head. Odontodes on head and trunk hypertrophied and arranged in longitudinal rows (most prominent on head). Eyes moderately small (13.9−17.6% in HL), dorsolaterally positioned. Lips roundish with papillae uniformly distributed on base of dentary and premaxilla and slightly decreasing distally. Lower lip larger than upper lip; its border fringed. Maxillary barbel present; joined to lower lip by membrane for half its length. Teeth slender and bicuspid; mesial cusp larger than lateral cusp. Premaxillary teeth 11−18. Dentary teeth 11−15.
Dorsal-fin ii,7; dorsal-fin spinelet short and V-shaped; dorsal-fin lock functional; dorsal-fin origin slightly posterior to pelvic-fin origin. Tip of adpressed dorsal fin almost reaching end of anal-fin base. Pectoral-fin i,6; its tip almost reaching middle of pelvic-fin unbranched ray length when depressed. Pectoral axillary slit present between pectoral-fin insertion and lateral process of cleithrum. Pectoral spine supporting odontodes on ventral, anterior and dorsal surfaces. Pelvic-fin i,5; tip of pelvic-fin longest ray almost reaching anal-fin origin when depressed in females and reaching anal-fin origin in males. Pelvic-fin unbranched ray with dermal flap along its dorsal surface in males. Anal-fin i,5; its tip reaching 7th or 8th plate from its origin. Caudal-fin i,14,i; distal margin forked. Adipose-fin absent. Total vertebrae 27.
Body covered with bony plates except above lower lip, around pectoral and pelvic-fin origins and on dorsal-fin base. Cleithrum and coracoid totally exposed.
Parts of dorsal head bone plates presented in
Pale yellowish ground color. Dorsal surface of head dark brown, except for pale yellowish areas on snout tip, lateral margin of head and tip of parieto-supraoccipital. Three dark-brown saddles crossing dorsum, reaching longitudinal dark stripe on side of trunk: first below dorsal-fin origin, second typically at adipose-fin region, and third at end of caudal peduncle. Ventral region of anal-fin origin with small single-chromatophore spots. Caudal fin hyaline with two black bars; first at caudal-fin origin, second at middle of caudal fin (
Adult males are distinguished by having a papilla at the urogenital opening (
Ventral view of abdominal region of three species of
Map of the distribution of
The specific epithet
MZUSP 115062, 26.2 mm SL, female, Brazil, Mato Grosso State, municipality of Santo Afonso, riacho Águas Claras, affluent rio Sepotuba, rio Paraguay basin,
All from Brazil, Mato Grosso State, rio Sepotuba basin. DZSJRP 18245, 2 females, 19.9−24.3 mm SL, collected with holotype. LBP 13347, 2 females, 18.9−19.6 mm SL, collected with holotype. LBP 13351, 9, 14.7−24.3 mm SL, riacho Águas Claras, Santo Afonso,
Morphometric data presented in
Head rounded in dorsal view. Snout slightly pointed, its tip rounded, elongated (50.7−57.1% HL) and depressed in front of each nostril on dorsal surface. Dorsal and ventral series of odontodes completely covering anterior margin of snout; odontodes of snout similar in size to remaining ones found on head. Snout tip lacking band devoid of odontodes. Odontodes on head and trunk well defined and arranged into longitudinal rows (character more prominent in head). Eyes small (11−14.1% HL), dorsolaterally positioned. Lips roundish and papillose; uniformly distributed on base of dentary and premaxilla and slightly decreasing distally. Lower lip larger than upper lip; its border strongly fringed. Maxillary barbel present. Teeth slender and bicupid; mesial cusp larger than lateral cusp. Premaxillary teeth 6−10. Dentary teeth 4−7.
Dorsal-fin ii,7; dorsal-fin spinelet short and V-shaped; dorsal-fin lock functional; its origin slightly anterior to pelvic-fin origin. Tip of adpressed dorsal-fin rays surpassing end of anal-fin base. Pectoral-fin i,6; tip of longest pectoral-fin ray almost reaching half of pelvic-fin length, when depressed. Pectoral axillary slit present between pectoral-fin insertion and lateral process of cleithrum. Pectoral spine supporting odontodes anteroventrally. Pelvic-fin i,5; its tip almost reaching anal-fin origin when depressed in females and reaching anal-fin origin in males. Pelvic-fin unbranched ray with dermal flap along its dorsal surface in males. Anal fin i,5; its tip reaching 7th and 8th from its origin. Caudal-fin i,14,i; distal margin emarginated. Adipose-fin absent. Total vertebrae 27.
Body covered with bony plates except on ventral part of head, around pectoral and pelvic-fin origin and on dorsal-fin base. Cleithrum and coracoid totally exposed.
Parts of dorsal head bone plates presented in
Ground color of dorsal and ventral region of head and trunk pale yellowish. Conspicuous longitudinal dark stripe enlarging from rostral plates to anterior corner of eyes, straightening and bordering on ventral margin of eyes, enlarging again through compound pterotic and lateral series of plates to caudal-fin. Another conspicuous longitudinal dark stripe starting medially at pre-nasal plate region and enlarging on supraoccipital region. Unpigmented portion of snout appears as hyaline v-shaped mark from rostral plate passing through nares to orbital margins. Longitudinal dark stripe from superior portion of sphenotic through mid-dorsal plates to posterior margin of dorsal-fin base. Dark blotch on compound pterotic overlaps mid-dorsal longitudinal dark stripe. Dark saddle on middle portion of predorsal region reaches mid-dorsal longitudinal dark stripe. Overall, pigmentation pattern forms geometric spots on anterodorsal region of body. Three dark saddles usually cross posterodorsal region of body, reaching longitudinal stripe on side of trunk: first saddle at middle of dorsal fin, second at adipose-fin region, and third at end of caudal peduncle. Saddles inconspicuous in some specimens. Ventral region of body almost completely pale yellowish, except few dark spots on caudal peduncle and dark ring at anal-fin origin. Dorsal, pectoral, and pelvic fins with dark chromatophores forming irregular sets of bands: three on dorsal and pectoral fin, and one on pelvic fin. Anal fin with few scattered chromatophores, sometimes forming bands. Caudal fin hyaline, except for dark spot on origin of rays, and dark band on middle of rays (
Adults males have a papilla in urogenital opening (
The species is known from three small tributaries the riacho Águas Claras, riacho Maracaña and riacho São Jorge, all draining to the rio Sepotuba, in the upper rio Paraguay basin (
The species name
Osteological characters are known to be conservative within
Cranial bones and dermal plates of the head of
All from Brazil, except when stated otherwise:
We thank Guilherme J. Costa Silva, Gabriel S. Costa e Silva and Fernanda O. Martins for helping with the osteology analysis and with the measurements; Ricardo C. Benine for providing laboratorial support; Renato Devidé, Weferson da Graça, Claudio Oliveira and Carla S. Pavanelli for helping with field work; Mahmoud Mehanna for cleared and double stained specimens; Nathan K. Lujan, Marcelo Melo, Ricardo C. Benine, Bruno F. Melo, Fernanda O. Martins and Danilo Pinhal for reading the manuscript and giving valuable suggestions. Logistical support was provided by Nupelia (Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura, Maringá, Paraná State, Brazil). This research was supported by the Brazilian agencies FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo, proc. 2010/01610-9 to FFR), MCT/CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) (Edital Universal, proc. N. 484716-2006-9 and grants to CHZ - proc. N. 310733/2013-8) and CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior).