Parotocinclus arandai, Sarmento-Soares & A. & Martins-Pinheiro, 2009

Sarmento-Soares, Luisa Maria, A., Pablo Lehmann & Martins-Pinheiro, Ronaldo Fernando, 2009, Parotocinclus arandai, a new species of hypoptopomatine catfish (Siluriformes: Loricariidae) from the upper rios Jucuruçu and Buranhém, States of Bahia and Minas Gerais, Brazil, Neotropical Ichthyology 7 (2), pp. 191-198: 192-195

publication ID

http://doi.org/ 10.1590/S1679-62252009000200009

persistent identifier

http://treatment.plazi.org/id/CF6B553B-FFEB-FFDD-FC53-FB98FECCFBCC

treatment provided by

Carolina

scientific name

Parotocinclus arandai
status

new species

Parotocinclus arandai   , new species

Fig. 1 View Fig

Holotype. MNRJ 28296 View Materials , female (38.7 mm SL), Brazil, Minas Gerais: Palmópolis, córrego Bananeiras on road Geribá-Palmópolis  

Species Distribution

1 P.   amazonensis Garavello, 1977 rio Amazonas basin  

2 P.   aripuanensis Garavello, 1988 rio Aripuanã basin  

3 P.   bahiensis ( Miranda Ribeiro, 1918) rio Itapecuru basin, northern Bahia State  

4 P.   bidentatus Gauger & Buckup, 2005 rio Paraíba   do Sul basin, Rio de Janeiro State

5 P.   britskii Boeseman, 1974 rio Orinoco basin and Atlantic coastal drainages of the Guianas

6 P.   cearensis Garavello, 1977 rio Choró , Ceará State  

7 P.   cesarpintoi Garavello, 1977 rio Paraíba   basin, Alagoas State

8 P.   collinsae Schmidt & Ferraris, 1985 rio Essequibo basin  

9 P.   cristatus Garavello, 1977 rio Almada basin and coastal rivers near Ilhéus , southern Bahia State  

10 P.   doceanus ( Miranda Ribeiro, 1918) rio Doce basin, Espírito Santo State  

11 P.   eppleyi Schaefer & Provenzano, 1993 upper and middle rio Orinoco basin

12 P.   haroldoi Garavello, 1988 rio Sanharó , Piauí State  

13 P.   jimi Garavello, 1977 rio de Contas basin, southern Bahia State  

14 P.   jumbo Britski & Garavello, 2002 rio Paraíba do norte basin and coastal rivers in Alagoas, Ceará, Paraíba and Pernambuco States

15 P.   longirostris Garavello, 1988 rio Amazonas basin  

16 P.   maculicauda (Steindachner, 1877) coastal rivers at Rio de Janeiro and Espírito Santo States  

17 P.   minutus Garavello, 1977 rio Vasa-Barris basin, northern Bahia State  

18 P.   muriaensis Gauger & Buckup, 2005 rio Paraíba   do Sul basin, Rio de Janeiro State

19 P.   planicauda Garavello & Britski, 2003 rio Doce basin, Espírito Santo State  

20 P.   polyochrus Schaefer, 1988 rio Negro drainage, Amazon basin  

21 P.   prata Ribeiro, Melo & Pereira, 2002 upper rio São Francisco

22 P.   spilosoma (Fowler, 1941) rio Paraíba   do Norte basin, Paraíba State

23 P.   spilurus (Fowler, 1941) rio Salgado , Ceará State  

(16º44’48”S 40º25’46”W), 26 Oct 2004, L. M. Sarmento-Soares, A. T. Aranda, C. C. Chamon & R. F. Martins-Pinheiro   .

Paratypes. 239 specimens (16.6-42.8 mm SL). Brazil, Minas Gerais: MNRJ 28297 View Materials (23, 26.7-42.8 mm SL) collected with the holotype. MBML 1484 (6, 16.8-27.2 mm SL), MNRJ 32049 View Materials (6, 16.6-30.1 mm SL), córrego Sete Ranchos on road Cotajás - Santo Antônio do Jacinto, near border of Minas Gerais / Bahia (16º38’04”S 40º17’52”W), 7 Jan 2007, L. M. Sarmento-Soares, A. T. Aranda , R. L. Teixeira & R. F. Martins-Pinheiro. MNRJ 28295 View Materials (76, 2 c&s, 16.6-38.6 mm SL), UF 18422 (4, 19.2-32.8 mm SL), ANSP 180644 View Materials (4, 19.2-32.8 mm SL), AMNH 235857 View Materials (4, 20.4-32.5 mm SL), AUM 42002 View Materials (4, 22.5-34.6 mm SL), córrego da Onça, at border of Bahia (Jucuruçu) and Minas Gerais (Palmópolis) States (16º49’49”S 40º15’05”W), 26 Oct 2004, same collectors as holotype. Brazil, Bahia: MBML 1486 (12, 31.8-38.0 mm SL), MBML 2135 (3 c&s, 26.5- 33.7 mm SL), MNRJ 32253 View Materials (87, 27.2-39.4 mm SL), MCP 43934 View Materials (3, 29.6-34.8 mm SL), and MCP 43935 View Materials (1 c&s, 30.2 mm SL), córrego Sete Ranchos on road Cotajás-Santo Antônio do Jacinto , near border of Minas Gerais / Bahia (16º36’03”S 40º17’04”W), 7 Jan 2007, L. M. Sarmento-Soares, A. T. Aranda, R. L. Teixeira & R. F. Martins-Pinheiro. MBML 1492 (6, 28.2-34.4 mm SL), MNRJ 32039 View Materials (19, 26.9-39.0 mm SL), córrego Sete Ranchos on road Cotajás- Santo Antônio do Jacinto , near border of Minas Gerais / Bahia (16º36’03”S 40º17’04”W), 7 Jan 2007, L. M. Sarmento-Soares, A. T. Aranda, R. L. Teixeira & R. F. Martins-Pinheiro GoogleMaps   .

Diagnosis. Parotocinclus arandai   is distinguished from all other Parotocinclus species   of the Guyana Shield, Amazonas and Orinoco basin (except P. collinsae   ) by the absence of a triangular patch of dark pigmentation at the anterior dorsalfin base. The new species differs from the P. collinsae   by the absence of the accessory teeth on the premaxilla and dentary. Parotocinclus arandai   differs from all congeners of the Atlantic coastal basins of southeastern and eastern Brazil by having the branched rays and interradial membranes of the pectoral and pelvic fins unpigmented in ventral view; the rostral plate not exposed ventrally (except P. bahiensis   , P. spilurus   and P. prata   ). The new species is distinguished from most Parotocinclus species   , except P. cristatus   and P. cesarpintoi   , by the presence of a tuft of hypertrophied odontodes on the supraoccipital; and by the extensively naked abdomen in adults, with a mosaic of few rounded platelets of irregular size and distributed over the pre-anal region (except P. bahiensis   , P. minutus   , P. spilosoma   , P. cearensis   , P. cesarpintoi   , and P. prata   ).

Other features for recognition of the new species are as follows: The pectoral girdle exposed medial and laterally ( Fig. 2a View Fig ) (vs. only laterally exposed in P. spilosoma   , P. cearensis   , P. cesarpintoi   , P. spilurus   , P. jumbo   , and P. prata   ); plates between anal and caudal fins 10 (vs. 9 in P. spilosoma   , P. cearensis   , P. cesarpintoi   , P. haroldoi   , P. spilurus   , and P. jumbo   ; and 11 in P. maculicauda   and P. doceanus   ); body deep, 16.1-18.6% SL (vs. less than 15% in P. cearensis   , P. cesarpintoi   , P. haroldoi   and P. minutus   ); small orbital diameter, 14.8-19.3% HL (vs. more than 20% in Parotocinclus bahiensis   , P. cesarpintoi   , P. cearensis   , P. cristatus   , P. haroldoi   , and P. jimi   ). Parotocinclus arandai   differs from the P. jimi   , P. planicauda   , and P. jumbo   by having all paired ribs associated with connective tissues of vertebrae, and from P. bahiensis   by the abdominal lateral plates 2-4 (vs. 5-7 in P. bahiensis   ).

Description. Morphometric and meristic data presented in Table 2. Body moderately short, robust, head and anterior trunk elevated. Dorsal profile of head from snout tip to anterior orbital rim arched; straight between supracleitrum and dorsalfin origin; slightly concave from near adipose-fin base to caudal-fin base. Ventral profile from snout to pectoral-fin base concave, straight from pectoral-fin base to anus and then slightly concave to caudal-fin base. Snout rounded in dorsal profile, rostrum convex; trunk ovoid in cross section anteriorly, progressing to elliptical to triangular posteriorly. Cross-section of caudal peduncle compressed laterally. Eyes small (14.8- 19.3% HL) and superior. Dorsal fin when depressed reaching to vertical through origin of anal fin. Pectoral fin reaching to just beyond pelvic-fin origin; pelvic fin reaching beyond anus, ending just anterior to anal-fin origin.

Head and trunk usually without keels; odontodes evenly distributed and regularly arranged on head and body; small tuft of hypertrophied odontodes present, on posterior portion of supraoccipital. Premaxillary teeth 21-28; dentary teeth 20- 30. Oral disk ovoid; lower lip with prominent papillae, variable in size; upper lip about half depth of lower lip. Short maxillary barbel present (5.3-6.5% SL). Infraorbitals five, two anteriormost larger than posterior ones. Infraorbital 3 in contact with prefrontal and second infraorbital, forming anterior corner of orbit. Infraorbital 4 with concave dorsal margin, forming ventral portion of orbital rim. Infraorbital 5 smallest, forming posterior orbital rim. Supraorbital crest conspicuous.

Posterior margin of supraoccipital followed by three plates on each side, medial pair sometimes fused together in one plate, followed by one pair and one azygous predorsal plate just anterior to dorsal-fin origin. Rostral margin with three postrostral bony plates between unpaired rostral plates on tip of snout. Rostral plate and subsequent postrostral plates around snout with slight ventral curvature. Dorsal rostral plate not exposed ventrally. First dorsal-fin spinelet small; spine of adipose fin prominent; adipose-fin origin vertically crossing at about end of adpressed anal-fin. Last anal-fin ray lacking posterior membrane. Abdomen with paired series of 2-4 small, median abdominal area naked, without platelets or with few rounded platelets of irregular size and distribution; region between pelvic fins with mosaic of few platelets, expanding over pre-anal shield region ( Fig. 2 View Fig ). A median row of platelets only in large sized specimens (larger than 24 mm SL). Young specimens (less than 24 mm SL) with platelets limited to pre-anal region. Lateral line incomplete with pores visible on first 5 or 6 anterior plates and sporadically along trunk between dorsal fin and caudal peduncle. Intermediate plates without pores 2-5.

Dorsal fin I,7; spinelet reduced in size, rounded or rectangular in shape. Nuchal plate present, trapezoid-shaped. Origin of dorsal fin at vertical behind pelvic-fin origin. Dorsal fin supported by 7 pterygiophores. Pectoral fin with one unbranched spine plus 6 branched rays. Pectoral-fin spine reaching pelvic-fin base when depressed. Pectoral girdle laterally and medially exposed; odontodes concentrated on lateral areas. Cleithrum largely exposed, coracoid covered by skin, exposed only near pectoral-fin spine attachment. Pectoral skeleton arrector fossae partially closed. Pelvic fin with one unbranched plus 5 branched rays. Pelvic fin margin rounded, not reaching anal-fin origin. Basipterygia sutured at midline, lacking fenestrae, ischiac process elongate. Anal fin with one unbranched plus 5 branched rays. Five anal-fin pterygiophores, each with one distal radial. First anal-fin pterygiophore large; subsequent ones become progressively shorter. Anal-fin margin truncated. Caudal fin 8+8-9, slightly forked; lobes equal with pointing tips; dorsal lobe procurrent caudal-fin rays 3; ventral lobe procurrent rays 3. Caudal-fin skeleton with parhypural fused with hypurals 1 and 2, separated by deep notch from hypurals 3 to 5 plus uroneural. Epural separated from dorsal hypurals. Vertebrae 22, excluding those incorporated into Weberian complex. Six paired pleural ribs, associated with connective tissues of vertebrae 8-13.

Color in alcohol. Irregular narrow dark brown stripe along trunk, between transverse dark bars, interrupted at certain points in some specimens. Ventral surface of head and belly whitish. Adipose fin with dark blotch at its base. Four irregular brownish bars on trunk; first one close to dorsal-fin origin, second at end of dorsal-fin base, third at adipose-fin origin, and fourth on caudal peduncle. Pelvic and anal fins with few and sparse chromatophores on dorsal side, not forming bands. Pectoral and pelvic fins with branched rays and interradial membranes unpigmented in ventral view. Caudal-fin base with dark vertical bar. Caudal fin with irregular color pattern, but inconspicuous darkened band always present at middle of each lobe. Ground color in ethanol becomes grayish.

Live coloration. Ground color pale yellow. Predorsal area of body mottled with faint small dark blotches ( Fig. 3 View Fig ). Longitudinal discontinuous stripe present along lateral line. Unbranched first ray in both dorsal and pectoral fins with alternate series of white and dark spots aligned, forming bands. Subsequent rays with alternate spots, giving maculate pattern to rays. Caudal-fin rays with dark chromatophores forming bands.

Distribution. Known from tributaries of the middle and upper rio Jucuruçu and upper rio Buranhém, close to the border of southern Bahia and northeastern Minas Gerais States ( Figs. 4 View Fig and 5 View Fig ).

Etymology. The specific name arandai   honors our ichthyologist colleague Arion Túlio Aranda in recognition of his talent for catching fish and knowledge of their habits.

Ecological notes. Parotocinclus species   are small herbivorous catfishes, but little is known about their habits. Benthic habits or behavior of attachment to submerged marginal vegetation were reported for different species groups by Garavello (1977) and information on diet is available for P. prata   in Ribeiro et al. (2002). During this study specimens were collected in clear, shallow waters, approximately 0.3 m in depth, in moderate flowing sections of the rivers, with a sandy or gravel bottom. Riparian environments were most impacted by agriculture and cattle, and surrounded by mild vegetation and with a few floating meadows.

T

Tavera, Department of Geology and Geophysics

R

Departamento de Geologia, Universidad de Chile

AUM

Auburn University Museum of Natural History

MCP

Pontificia Universidade Catolica do Rio Grande do Sul