Hypostomus nigropunctatus, Garavello & Britski & Zawadzki, 2012

Garavello, Julio César, Britski, Heraldo Antônio & Zawadzki, Claudio Henrique, 2012, The cascudos of the genus Hypostomus Lacépède (Ostariophysi: Loricariidae) from the rio Iguaçu basin, Neotropical Ichthyology 10 (2), pp. 263-283 : 277-281

Hypostomus nigropunctatus new species Fig. 7

Holotype. MZUSP 106072 , 184 , 4 mm SL, rio Iguaçu, Salto Segredo reservoir, Brazil, Paraná State, Municipality of Mangueirinha / Reserva do Iguaçu , 25º46’45”S 52º07’00”W, 3 Feb 1995, Nupélia.

Paratypes. All from Brazil. Paraná State. LBP 9214 , 1, 232.9 mm SL, rio Jordão (at its mouth), Municipality of Reserva do Iguaçu, 25º46’21”S 52º07’04”W, 8 Nov 1999, J. D. Latini. LISDEBE, 1, 204.0 mm SL, rio Butiá , Municipality of Mangueirinha , 25º59’23”S 52º04’39”W, 5 Nov 1994, Nupélia. MHNCI 12328 , 1, 178.1 mm SL, rio Covó , Municipality of Mangueirinha , 25º58’13”S 52º09’10”W, 3 Feb 1996, Nupélia. NUP 5081 , 1 , 84.3 mm SL; downstream Salto Segredo reservoir, rio Iguaçu , Municipality of Mangueirinha / Reserva do Iguaçu , 25º45’S 52º05’W, 3 Feb 1995, Nupélia. NUP 5082 , 1, 171.4 mm SL, rio Jordão (at its mouth), Municipality of Reserva do Iguaçu , 25º46’17”S 52º06’51”W, 26 Nov 1996, Nupélia. NUP 5083 , 1, 208.4 mm SL, rio Covó , Municipality of Mangueirinha , 25º58’13”S 52º09’10”W, 3 Dec 1993, Nupélia. NUP 5084 , 2 , 224.0-230.0 mm SL, rio Covó , Municipality of Mangueirinha , 25º58’13”S 52º09’10”W, 4 Feb 1994, Nupélia. NUP 5085 , 1, 200.5 mm SL, rio Covó , 25º58’13”S 52º09’10”W, Municipality of Mangueirinha , 3 Feb 1999, Nupélia. NUP 7518 , 1, 173.8 mm SL, rio Covó , Municipality of Mangueirinha , 25º58’13”S 52º09’10”W, 4 Feb 1994, Nupélia. NUP 7519 , 1 , 224.0 mm SL, rio Covó , Municipality of Mangueirinha , 25º58’13"S 52º09’10”W, 2 Dec 1994, Nupélia. ZSM 34136 , 1, 176.1 mm SL, rio Covó , 25º58’13”S 52º09’10”W, Municipality of Mangueirinha , 4 Feb 1995, Nupélia .

Diagnosis. Hypostomus nigropunctatus can be distinguished from the species of the H. cochliodon group, except H. hemicochliodon , by having bifid non spoon-shaped teeth and with the lateral cups not fused to the mesial one (vs. spoon-shaped teeth with lateral cups usually fused to the mesial one). From H. alatus , H. albopunctatus , H. chrysostiktos , H. faveolus , H. francisci , H. lexi , H. luteus , H. luteofrenatus , H. margaritifer , H. microstomus , H. multidens , H. regani , H. roseopunctatus , H. scaphiceps , H. strigaticeps , H. tietensis and H. variipictus it is distinguished by having dark spots over body and fins (vs. pale spots). It is distinguished from the remaining congeners, except H. agna , H. brevicauda , H. brevis , H. derbyi , H. garmani , H. goyazensis , H. heraldoi , H. hermanni , H. iheringii , H. johnii , H. lima , H. luetkeni , H. macrops , H. nigromaculatus , H. ternetzi , H. topavae and H. wuchereri , by the absence of keels on pterotic-supracleitrhum, pre-dorsal plates and on lateral series of plates (vs. having moderate to developed keels on pterotic-supracleitrhum, pre-dorsal plates, and lateral series of plates). From H. agna , H. brevicauda , H. heraldoi , H. hermanni , H. garmani , H. johnii , H. luetkeni , H. nigromaculatus , H. vermicularis , and H. wuchereri by having deeper body and a pair of parallel moderate keels on pre-dorsal plates (vs. depressed body without keels on pre-dorsal plates). From H. brevis , H. goyazensis , H. johnii , H. iheringii , H. lima , H. ternetzi , and H. topavae by having abdomen completely plated (vs. abdomen naked in H. brevis and partially plated in H. goyazensis , H. iheringii , H. kuarup , H. johnii , H. lima , H. macrops , H. ternetzi , and H. topavae ). From H. derbyi by having small-sized and close-settled dark spots (equal to smaller than eye pupil) on dorsal region of head, trunk, and fins (vs. middle-sized and moderate-settled dark spots (approximately equal to eye diameter length) on dorsal region of head, trunk, and fins); and by having three pre-dorsal plates bordering supraoccipital (vs. usually one plate).

Description. Dorsal profile of head slightly concave from tip of snout to supraoccipital; supraoccipital elevated and forming an inconspicuous keel; pre-dorsal plates slightly concave. Head elevated and slightly compressed, totally covered by plates with fine odontodes. A conspicuous keel subsequent to pterotic-supracleithrum region behind orbit, conspicuously followed by subsequent trunk plates to caudal peduncle; a divergent keel on median portion of supraoccipital, running by dorsal plate series to caudal fin, giving to dorsal region of caudal peduncle a slightly quadrangular aspect. Snout narrow and compressed covered by irregular series of small plates; an inconspicuous keel running from snout tip to upper region of orbit. Orbits elevated, positioned nearly lateral; orbital diameter 10.9-12.5% in head length. Posterior region of head covered by two unpaired elongate plates between supraoccipital and dorsal-fin insertion; an unpaired nuchal plate enclose first dorsal-fin spinelet. Supraoccipital and pterotic-supracleithrum densely covered by odontodes mainly along keels. Nare large, its diameter nearly twice in intranasal distance. Dorsal profile of trunk slightly declining from dorsal-fin insertion to caudal fin. Adipose-fin spine large and situated seven plates after dorsal-fin insertion.Anterior plates of longitudinal trunk series after scapular bridge with a conspicuous keel. Maximum width at scapular bridge gradually decreasing to caudal fin. Dorsal fin II,7; dorsal-fin insertion at two plates before vertical through pelvic-fin insertion; not reaching adipose-fin spine; its distal margin convex. Pectoral fin I,6 rays; unbranched ray elongate, with large odontodes on distal margin; surpassing pelvic-fin insertion when adpressed; its distal margin almost straight. Pelvic fin i,5 rays; posterior margin truncate; unbranched ray reaching or surpassing anal-fin insertion. Anal fin, i,5; distal border slightly rounded. Caudal fin i,14,i rays, slightly notched; lower lobe longer than upper.

Body covered by five lateral series of plates not forming conspicuous keels; odontodes more concentrated along keeled areas of integument. Rostral margin of snout aciculate; ventral view of labial insertion deeply notched. Snout tip formed by junction of upper lip that is covered by irregular series of small plates; odontodes restricted to plated area extending from upper supraoccipital to distal pterotic-supracleithrum. Scapular bridge totally covered by skin and small plates with minute odontodes covering nearly all abdomen; naked areas only in front of pelvic-fin insertion; two pair of narrow plates between anal-fin insertion and anus. Twenty eight plates in lateral line. Lips and oral region semicircular with dense papillae; labial barbel short and free from labial margin. Premaxilla with 32-38 and dentary with 29- 43 fine and short teeth with cusps nearly equal in size.

Color pattern. Ground color of head and trunk dark brown uniform; dorsal region of head and trunk densely spotted with fine black spots. Interradial membranes of all fins excepting caudal fin intermittent black spotted; unbranched rays of all fins light brown uniform; black spotted intermittent from space to space on upper region and light brown in lower regions. Unbranched rays and interradial membranes of caudal fin black spotted, forming six transversal black bars crossing both lobes of caudal fin. Abdominal region light brown, irregularly black spotted or vermiculated on whole abdomen and lower caudal peduncle. Unbranched ray of pectoral, pelvic, anal and caudal fins light brown in lower regions but black spotted on upper regions.

Distribution. Known from rio Iguaçu, Paraná State, Brazil. Hypostomus nigropunctatus is known from the middle stretches of the rio Iguaçu, at Salto Segredo reservoir and at the mouth of rios Covó and Jordão.

Figures

Fig. 7. Holotype of Hypostomus nigropunctatus n. sp., MZUSP 106072, 184.4 mm SL, rio Iguaçu, Municipality of Mangueirinha/ Reserva do Iguaçu, Paraná, Brazil.