Ituglanis paraguassuensis , Campos-Paiva, Rafael M. & Costa, Wilson J. E. M., 2007

Campos-Paiva, Rafael M. & Costa, Wilson J. E. M., 2007, Ituglanis paraguassuensis sp. n. (Teleostei: Siluriformes: Trichomycteridae): a new catfish from the rio Paraguaçu, northeastern Brazil, Zootaxa 1471, pp. 53-59: 55-58

publication ID

10.5281/zenodo.176686

publication LSID

lsid:zoobank.org:pub:B5779D1E-F9FF-4D49-8E9A-D2785BE42BAD

persistent identifier

http://treatment.plazi.org/id/03F687CE-D76A-3F31-29FA-5CAEFB16E67F

treatment provided by

Plazi

scientific name

Ituglanis paraguassuensis
status

new species

Ituglanis paraguassuensis  new species

( Fig. 1View FIGURE 1)

Holotype. LIRPAbout LIRP 5780, 41.2 mm SL; Brazil: Estado da Bahia, rio Paraguaçu near Iassu, side channel far from main river channel, forming pool with current (12 º 45 ’ S, 40 º 12 ’ W); S. L. Jewett and R. M. C. Castro, 25 July 1988.

Paratypes. LIRPAbout LIRP 5834, 5 ex., 34.8–41.3 mm SL; UFRJ 7209, 1 ex., 36.5 mm SL; UFRJ 7282, 1 ex., 39.6 mm SL (c&s); USNMAbout USNM 301016, 5 ex., 33.7–41.6 mm SL (2 c&s), 30.3–37.8 mm SL, all collected with the holotype.

Diagnosis: Distinguished from all other species of the genus by the following combination of characteristics: color pale yellow on lateral and dorsal regions of head and body, whiter on ventral. Skin covered by several irregular pale brown blotches aligned along the body (vs. distinct color patterns in all other Ituglanis  ); pectoral fin-rays i, 6 (vs. i, 4 in I. macuniama  , I, cahyensis  and I. parahybae  ; i, 5 in I. amazonicus  , I. eichorniarium  , I. metae  and I. nebulosus  ; i, 7 in I. bambui  , I. passensis  , I. epikarsticus  ; i, 8 in I. ramiroi  except in I. parkoi  , I. proops  and I. laticeps  ); pelvic-fin-rays i, 4 (vs. i, 3 in I. eichorniarium  and I. cahyensis  or pelvic-fin absent in I. parahybae  ; i, 5 in I. amazonicus  , I. passensis  except in I. gracilior  , I. nebulosus  , I. macunaima  , I. bambui  , I. ramiroi  , I. epikasticus  , I. parkoi  , and I. guayaberensis  ); parietal fontanel extending to posterior edge of medial parietal border ( Fig. 2View FIGURE 2) (vs. parietal fontanel reduced or vestigial, restricted to middle of medial parietal border in all other Ituglanis  except in some I. amazonicus  and I. proops  ); the unusual reduced number of vertebrae 34–36, where vertebral counts normally range 39 or more (in I. amazonicus  , I. cahyensis  , I. eichorniarium  , I. parahybae  , I. proops  , I. gracilior  , I. herberti  , I. metae  , Ituglanis  sp. A).

Description: Morphometric data for holotype and paratypes are given in Table 1. Body elongated, subcylindrical, compressed in caudal peduncle. Dorsal profile straight on head, convex between nape and dorsal-fin origin, approximately straight on caudal peduncle. Ventral profile straight to slightly convex between lower jaw and end of anal-fin base. Lips and barbels covered by minute papillae.

Dorsal-fin origin on vertical between centrum of 19 th and 21 st vertebrae. Anal-fin origin on vertical through base of 6 th and 8 th segmented dorsal-fin rays and through the centrum of 22 nd and 24 th vertebrae. First pectoral-fin ray filamentous and 20 to 30 % longer than other pectoral-fin rays. Tip of pelvic-fin reaching vertical between base of 4 th and 6 th segmented dorsal-fin rays. Caudal-fin subtruncate. Dorsal-fin rays 12–13 (5,vii or 5,viii); anal-fin rays 9–10 (4,v or 5,v); pectoral-fin rays 7 (i, 6); pelvic-fin rays 5 (i, 3,i); caudal-fin principal rays 13, dorsal procurrent rays 14–15, ventral procurrent rays 11–12. Total vertebrae 34–36; epipleural ribs 6; upper hypural plate united.

Head trapezoidal in dorsal view. Eye located on anterior half of head. Mouth subventral. Maxilla longer than premaxilla. Premaxilla trapezoidal with about 20 conical teeth, arranged in two irregular rows. Dentary slender, with about 25 conical teeth, arranged in two or three irregular rows. Tip of nasal barbel reaching posterior edge of opercular patch of odontodes; tip of maxillary barbel reaching pectoral-fin base; tip of rictal barbel reaching anterior edge of opercular patch of odontodes. Branchiostegal rays 8. Hypobranchials ossified; two anterior basibranchials ossified, third basibranchial consisting of rounded cartilage. Interopercular odontodes 15; interopercular patch of odontodes about equal to preopercle in length; opercular odontodes 14–17. Odontodes conical. Cephalic laterosensory canal with simple tubes ending in simple pores, continuous and connected to each other on pterotic, sphenotic and lateral border of parietal ( Fig. 2View FIGURE 2). All cephalic pores paired: supraorbital 4; s 1 and s 2 connected by single canal; s 1 between palatine and mesethmoid, s 2 on vomer. s 3 on vomer, s 6 on parietal; connected to one another. Infraorbital 4; i 1 and i 3 connected by single canal; both situated next to antorbital; i 10 and i 11 connected, on sphenotic. Preopercular 1; on pterotic. Lateral line 3, all connected; ll 1 on postemporo- supracleithrum, ll 2 and ll 3 on lateral side of body near opercle. Parietal fontanel extending to posterior border of parietal; postparieto-supraoccipital fontanel restricted to middle region; sphenotic narrow, anterior tip anteriorly directed ( Fig. 2View FIGURE 2). Mesethmoid somewhat widened, about equal in width to anterior portion of palatine; autopalatine with deep concavity along medial border; posterior process of palatine moderate, length about 50 % of length of autopalatine without such process. Supraorbital tendon bone elongate and robust, becoming slender and curved outwards, approximately equal to autopalatine in length ( Fig. 2View FIGURE 2); no process on supraorbital tendon bone ( Fig. 2View FIGURE 2). Metapterygoid moderate, longest length about 60 % of horizontal length of quadrate; dorsal portion of quadrate anteriorly expanded ( Fig. 3View FIGURE 3). Urohyal lateral wing somewhat elongate, about equal to anterior ceratohyal in length. Two pectoral radials, first cartilaginous, second ossified, length of latter about twice first. Neural prezygapophyses conspicuous in all vertebrae.

Coloration in alcohol: Lateral and dorsal regions of head and body pale yellow, with pale brown rounded blotches. Dark brown pigmentation concentrated on head, in front of eyes, and in front of opercular and interopercular odontodes patches. Nasal and maxillary barbels whitish with dark brown marginal pigment. Rictal barbel whitish. Dorsal and caudal fins hyaline with small concentrations of dark brown chromatophores scattered on fin rays. Pectoral, pelvic and anal fins whitish. The blotches may vanish in alcohol.

Distribution: Known only from the type locality, rio Paraguaçu near Iassu, Estado da Bahia, northeastern Brazil.

Etymology: The name paraguassuensis  refers to the type locality, rio Paraguaçu.

TABLE 1. Morphometric data of Ituglanis paraguassuensis n. sp. H: holotype (LIRP 5780)

  H Paratypes range (n= 14) Average
Percents, standard length
LIRP

Laboratorio de Ictiologia, Faculdade de Filosofia

USNM

Smithsonian Institution, National Museum of Natural History