Tatia neivai ( Ihering, 1930 )

Sarmento-Soares, Luisa Maria & Martins-Pinheiro, Ronaldo Fernando, 2008, A systematic revision of Tatia (Siluriformes: Auchenipteridae: Centromochlinae), Neotropical Ichthyology 6 (3), pp. 495-542 : 529-531

Tatia neivai ( Ihering, 1930)

Fig. 33-35

Tatia intermedia . Miranda Ribeiro, 1918: 734 [Piquete & Piracicaba, São Paulo]. Fowler, 1951: 470 [literature compilation]. Miranda Ribeiro, 1962: 10 [reference].

Glanidium neivai Ihering, 1930: 99 , pl. 13, fig. 1 [type locality: Piracicaba river, Piracicaba, São Paulo]. Gosline, 1945: 11 [listing]. Miranda Ribeiro, 1962: 3 [reference].

Tatia neivai . Mees, 1974: 71-74, fig. 16 [notes and distribution]. Sands, 1984: 42 [listing]. Burgess, 1989: 242, pl. 108 [reference]. Soares-Porto, 1998: 333 [citation]. Britski et al., 1999: 113 [Pantanal Mato-Grossense]. Casatti et al., 2001:5 [upper Paraná river]. Nakatani et al., 2001: 248 [larval development]. Ferraris, 2003:477 [check list]. Veríssimo et al., 2005: 7 [Manso river]. Ferraris, 2007: 77 [check list].

Tatia cf. aulopygia . Mees, 1988: 409 fig. 1 [ Paraguay]. Burgess, 1989:242 [reference].

Diagnosis. Tatia neivai is distinguished from other species of Tatia by its unique color pattern with scattered small white spots over the sides of the body and the caudal fin with dark vertical bars. The species is also distinguished by the following combination of characters: third nuchal plate broad, with short lateral projection, and post-Weberian vertebrae alternatingly ribbed and unribbed.Additional features useful for distinguishing the species include: caudal-fin lobes of equal length in mature females, upper lobe more elongated in mature males; 31-33 post-Weberian vertebrae.

Description. Measured adult specimens 48.1-82.1 mm SL; morphometric data presented in Table 11. Body slim, head slightly depressed dorso-ventrally. Head large, robust, dorsal profile of head elliptic, broader than long. Dorsal outline of trunk from dorsal-fin base to caudal peduncle gradually compressed posteriorly. Lateral profile of head from snout tip to above opercular margin slightly convex until pectoral-fin insertion. Ventral profile of head and abdomen flat. Ventral profile of body concave posterior to anal fin.

Head integument thin, cranial roof visible; well-developed adipose eye lid; eye latero-dorsally located in anterior portion of head; mouth terminal, upper lip extended posterolaterally as well-developed fleshy rictal fold; snout margin rounded; anterior nostril tubular, located on anterior border of snout; posterior nostril large, rounded, limited by small skin flap; transverse distance between anterior nostrils slightly larger than distance between posterior ones. Maxillary barbel moderate in size, extending to posterior tip of postcleithral process, sometimes longer; mental barbel arranged in arc along ventral surface of jaw, tips not reaching pectoral-fin base; inner mental barbel about 60.0-70.0% length of outer mentals. Postcleithral process well developed, almost reaching vertical through middle of dorsal fin. Caudal peduncle moderately deep, its depth about 13.6-14.8% SL.

Rostral border of cranium with mesethmoid as broad as long; premaxilla underneath with synchondral articulation; cranial fontanel narrow, elliptical, bounded by mesethmoid and frontal ( Fig. 33 ); nasal ossified, with short medial flanges partially sutured to lateral margin of mesethmoid; autopalatine tubular, oriented obliquely to longitudinal axis of body; maxilla small, shorter than autopalatine; prevomer expanded anteriorly, with well developed arrow-shaped lateral processes; jaws of equal size; premaxilla and dentary with three to four rows of conical teeth. First nuchal plate short, somewhat elliptical; second nuchal plate laterally concave, partially in contact with supraoccipital in some specimens; third nuchal plate relatively straight, projected laterally. Epioccipital process small.

Suspensorium, hyoid arch, branchial skeleton and opercular bones as in generic description. Suprapreopercle present as a very short canal bone. Six branchiostegal rays articulated with hyoid arch: four with anterior ceratohyal and two with posterior ceratohyal; last one largest and expanded.

Five infraorbital bones in incomplete series. Infraorbital 1 broad, with short developed ventro-lateral process around anterior border of eye; remaining infraorbitals thin, reduced to canalicular portions. Infraorbital 2 smallest, close to infraorbital 1, followed by non-ossified portion of canal below eye and by three posterior canal bones forming posterior orbital rim. Lateral line on body with ossified canal bones limited to head.

Dorsal fin I,4-5, rarely I,4 (n=25); dorsal-fin spine with 12- 15 antrorse serrations along entire margin; posterior margin smooth. Pectoral fin I,4-5, rarely I,5 (n=25); pectoral-fin spine with 19-24 antrorse serrations along anterior margin, small serrations close to spine base; 13-17 retrorse serrations along posterior margin; serrations along both margins progressively larger towards spine tip. Pelvic-fin i,5 (n=25), margin rounded. Adipose fin short, origin on vertical through end of anal-fin base.Anal fin iii, 6-7, rarely iii,6 (n=25); anal-fin pterygiophores in eight rod-like proximal radials and seven cartilaginous distal radials. Caudal fin forked, lobes with rounded tips, 8+9 principal rays, 19-21 upper procurrent, 19-20 lower procurrent rays (n=25). Seven or nine pleural ribs attached to consecutive vertebrae plus one attached to 9 th or 11 th vertebrae. The 8 th or 10 th vertebrae correspond to gap, with no ribs attached. Ribs progressively small anteroposterioly. Post-Weberian vertebrae 31-33 (n=4).

Color in alcohol. Color pattern usually with scattered small white spots over lateral sides of body mainly distributed over ventrolateral parts. Dorsal spine usually with transverse bands; pectoral-fin spine not pigmented. Caudal fin with irregular dark vertical bars. Posterior nuchal plates somewhat pale. Lips and nostrils whitish. Ventral portion of head around chin light brown.

Color variation. Regional variation in coloration was observed regarding specimens from the upper Paraná river immediately above the Sete Quedas waterfalls (MHNG 2355.92). These specimens have a dark body coloration, with only a few white spots ventrally, and a caudal fin with vertical bars. Some specimens from the upper Paraguay river in the Pantanal of Mato Grosso are light brown over dorsal parts of the body, with scatteredspots along ventrolateral parts of body, and with a vertically barred caudal fin.

Sexual dimorphism. Based on examination of gonads, T. neivai attains sexual maturity above 48.1 mm SL. A genital papilla is not evident in females. The genital papilla of mature male is visible, with a short deferent duct. Male anal fin ( Fig. 35 ) is modified with the three unbranched and first branched rays enlarged and thickened. First unbranched ray is nonsegmented, and immediately preceded by a tegumentary keel ( Fig. 35 , tk). The second unbranched ray is elongated, coalescing towards fin tip. The third unbranched and first branched rays are the longest, forming a short fin tip. The third unbranched ray has two antrorsely curved distal segments ( Fig. 35 , al). The first branched ray has four or five retrorsely curved distal segments ( Fig. 35 , rl).The posterior branched rays become progressively shorter, with the last ray not reduced ( Fig. 35 , b 7 ).

Hemal spines 14-17 are interdigitating with the anal-fin pterygiophores. The hemal spines 15-17 are thick in mature males, but undifferentiated in females. The male upper caudal-fin lobe is slightly elongate, about 15.0% longer than the lower lobe, whereas in mature females there are equal lobes.

Distribution. Tatia neivai occurs in the upper Paraguay river, in the Pantanal of Mato Grosso, Brazil, upper Paraná river, and upper Paraíba do Sul river ( Fig. 6 ). It is recorded from several tributaries of the upper Paraná river, Brazil, such as the Grande river in Minas Gerais, the Tietê and Paranapanema rivers in São Paulo, and the Tibagi river in Paraná. In the upper Paraíba do Sul river the species was recorded from Piquete, São Paulo State. The single record from the São Francisco river is uncertain (MZUSP 3801) because the locality data are dubious.

Remarks. Tatia neivai was observed in semi-lotic environments. Some of these catfishes were found hidden within marginal vegetation or were captured inside crevices of submersed trunks (O. Shibatta pers. comm.).

Tatia neivai was described based on a single specimen from the Piracicaba river. The holotype is lost, but Ihering (1930: pl. 13) illustrated the specimen as having irregularly scratched color pattern on the sides of the body and the caudal fin with dark vertical bars. This color pattern distinguishes T. neivai from most Tatia species , except some T. aulopygia . Variation in coloration may occur among populations, but the caudal fin is always barred, and sometimes resembles that of T. aulopygia . In spite of this similarity, T. neivai and T. aulopygia can be distinguished on the basis of proportional measurements, the size of cranial fontanel (bounded by mesethmoid and frontal in T. neivai vs. restricted to frontal in T. aulopygia ); the modified anal fin of adult males (distal margin continuous, without notch in T. neivai vs. notched in T. aulopygia ) and the post-Weberian vertebrae (31-33 in T. neivai vs. 38-39 in T. aulopygia ).

Material examined. 60 specimens (23.1-82.1mm SL). Brazil: Goiás: NUPELIA unnumbered, 1, (58.4 mm SL), Corumbá river, near Ipameri, Pires do Rio District. Mato Grosso do Sul: MZUSP 35882 , 1 (26.6 mm SL), Piquiri river , Santo Antônio do Paraíso farm, Itiquira; MZUSP 36364 , 2 (27.7-46.8 mm SL), Corixão, Capão Grande, Nhecolândia, Corumbá; MZUSP 42145 , 2 (23.6-33.9 mm SL), lake about 25 Km from Poconé, on road to Porto Cercado. Paraná: MZUEL 206 , 1 (56.0 mm SL); MZUEL 207 , 1 (53.7 mm SL); MZUEL 1098 , 1 (63.5 mm SL), Tibagi river , município de Sertanópolis. Minas Gerais: MNRJ 28722 , 2 (61.1-76.4 mm SL), Grande river , upstream from Porto Colombia dam. São Paulo: MZUSP 1993 , 1 (62.1 mm SL), Piquete; MZUSP 2000 , 1 (54.4 mm SL), Piracicaba river ; MZUSP 35360 , 1 (62.3 mm SL), Araguá river , Botucatu; MZUSP 42569 , 2 (58.2 mm SL), Piracicaba river , Piracicaba; MZUSP 42570 , 1 CS (60.5 mm SL), lake on Atibaia river , near Jaguariuna; MZUSP 45099 , 1 (48.9 mm SL), Tietê river , Itápolis; MZUSP 46009 , 1 (56.0 mm SL), Corumbataí river , Corumbataí; MZUSP 46855 , 2 (23.1-41.0 mm SL), Pardo river , near Guaíra; MZUSP 47505 , 7 (53.1-62.1 mm SL), ilha Solteira , Paraná river , Ilha Solteira dam. Paraguay: MHNG 2159.45 , 1 (56.7 mm SL), Itapua: Tembey river . MHNG 2353.30 , 1 (48.0 mm SL), salto Pirareta, La Cordillera. MHNG 2355.92 , 12 (50.7-63.7 mm SL), Caaguazu: Yuguyry stream, about 17 Km south of Yhu. MHNG 2430.19 , 1 ( R) (76.1 mm SL), lake on Iguazu river , upper Paraná. MHNG 2480.48 , 1 (82.1 mm SL). MHNG 2480.49 , 1 (43.6 mm SL), Canindeyú: Salto Guaira, Itaipu lake . MHNG 2537.73 , 8 , 1 CS, (37.2-46.6 mm SL), Tagatija-mi river , about 30 Km east from Puerto Max; UMMZ 206602 , 3 (29.6-30.4 mm SL), Aguaray river , San Pedro; USNM 249826 , 1 (54.5 mm SL), Canindeyú: Carapa river , above waterfalls, old road from Stroessner to Guaira; ZMA 116.801 , 1 ( R) (66.2 mm SL), Itapua: Tembey river , 4 Km above cataracts .

Figures

Fig. 33. Tatia neivai. (a) MHNG 2355.92, male, 51.6 mm SL. (b) MHNG 2355.92, female, 53.3 mm SL, Yuguyry stream, Paraguay.

Fig. 34. Neurocranium of Tatia neivai, MZUSP 42570, 60.5 mm SL. Dorsal view.Abbreviations: ep, epioccipital; fo, single cranial fontanel, fr,frontal; le, lateral ethmoid; me,mesethmoid; na, nasal; n1, first nuchal plate, n2; second nuchal plate; n3, third nuchal plate; pe, posterior epioccipital process; ps, posttemporal-supracleithrum; pt, pterotic; so, supraoccipital; sp, sphenotic. Scale bar = 1 mm.

Fig. 35. Male modified anal fin of Tatia neivai, MZUEL 206, 56.0 mm SL. Leftside lateral view.Abbreviations:ac, antrorsely curved denticulation; b7, branched seventh ray; dd, deferent duct; rc, retrorsely curved denticulation; tk, tegumentary keel; ui, unbranched first ray; uii, unbranched second ray; uiii, unbranched third ray. Scale bar = 1.0 mm.

Fig. 7. Tatia aulopygia, (a) INPA 11080, male, 104.6 mm SL, Guaporé river, Amazonas State, Brazil. (b) ZMA 114.280, young female, 46.3 mm SL, Humaitá,Amazonas State, Brazil.

Fig. 6. Drainage map of northern South America illustrating the geographic distribution of the species of Tatia. Symbols may represent more than one locality. Base map by Marilyn Weitzman.