Austrolebias salviai, Wilson J. E. M. Costa, 2006

Wilson J. E. M. Costa, 2006, The South American annual killifish genus Austrolebias (Teleostei: Cyprinodontiformes: Rivulidae): phylogenetic relationships, descriptive morphology and taxonomic revision., Zootaxa 1213, pp. 1-162 : 137-139

Austrolebias salviai Costa, Litz & Laurino, new species

(Fig. 51)

Material examined

Holotype. MUNHINA 3208 , male, 45.9 mm SL; Uruguay: Treinta y Tres, Paso del Dragon , temporary swamp near rio Tacuari , laguna Merin basin , 32°45.95’S 53°43.19’W; P. Laurino, T. Litz, H. Salvia & J. Salvia, 30 Aug. 2004.

Paratypes. Uruguay: Treinta y Tres: MUNHINA 3209 , 1 male, 42.4 mm SL, 1 female, 36.2 mm SL; UFRJ 6169 , 3 males, 28.4-42.7 mm SL, 5 females, 27.5-39.4 mm SL; UFRJ 6170 , 1 male, 45.3 mm SL, 3 females, 33.0-40.2 mm SL (c&s); ZSM 33389 , 4 males, 21.6-37.9 mm SL, 4 females, 26.3-36.9 mm SL; collected with the holotype . UFRJ 6171 , 1 male, 29.6 mm SL, 1 female, 29.8 mm SL; CIMC 9567 , 2 males, 25.7-29.8 mm SL, 4 females, 26.2-31.1, 6; MUNHINA 3210 , 2 males, 27.7-28.3 MM SL, 5 females, 26.4-32.5 mm SL; ZSM 33390 , 1 male, 28.1 mm SL, 3 females, 29.2-31.9 MM SL; same locality , 32°45.95’S 53°43.16’W; P. Laurino, T. Litz, H. Salvia & J. Salvia, 30 Aug. 2004.

Diagnosis

Distinguished from A. charrua , A. minuano , A. nigrofasciatus , and A. nachtigalli in having all flank bars narrower than adjacent interspace; differs from A. charrua , A. minuano , and A. adloffi by having a broad black bar on the posterior portion of the dorsal and anal fins (vs. black bar absent) and light blue bars on dorsal fin in males (vs. dots or elongate spots); from A. charrua by a distinctive black bar on parietal series of neuromasts; from A. adloffi by fewer anal-fin rays (22-25 in males and 21-23 in females, vs. 26-30 in males and 23-26 in females); from A. minuano by smaller maximum body depth in older males (43.4 % SL vs. 51.2 % SL) and fewer teeth on second pharyngobranchial in larger specimens (2 vs. 6-7); from A. nigrofasciatus and A. nachtigalli by more vertebrae (29-31 vs. 27-29); from A. nigrofasciatus by more caudalfin rays (22-25 vs. 19-22) and the absence of light blue bars on the anal fin in males (vs. presence); and from A. nachtigalli by a longer snout (16.4-18.6 % HL, vs. 12.6-15.3 % HL) and narrower head (61.4-66.6 % HL, vs. 66.6-71.4 % HL).

Description

Morphometric data appear in Table 9. Males larger than females, largest male examined 45.9 mm SL, largest female 39.4 mm SL. Dorsal profile convex from snout to end of dorsal-fin base, approximately straight on caudal peduncle; often pronounced gibbosity on frontal region of head in males. Ventral profile convex from lower jaw to end of anal-fin base, nearly straight on caudal peduncle. Greatest body depth at level of pelvicfin base. Body deep and compressed. Snout blunt and jaws short.

Tip of both dorsal and anal fins rounded. Anteromedian rays of anal fin of females lengthened, anal fin shape nearly triangular; distal portion of anal fin thickened in females. Caudal fin rounded. Pectoral fins elliptical, posterior margin on vertical between base of 2 nd and 5th anal-fin rays in males, and through urogenital papilla in females. Tip of each pelvic fin reaching between base of 3rd and 4th anal-fin rays. Medial pelvic-fin membranes 10-60 % coalesced. Urogenital papilla not attached to anal fin. Dorsal-fin origin on vertical through 1st or 2nd anal-fin ray, or sometimes slightly anterior to anal-fin origin, between neural spines of 9th and 10th vertebrae in males, between neural spines of 10th and 12th vertebrae in females. Anal-fin origin between pleural ribs of 9th and 10th vertebrae in males, between pleural ribs of 10th and 11th vertebrae in females. Dorsal-fin rays 20-23 in males, 17-20 in females; anal-fin rays 22-25 in males, 20-23 in females; caudal-fin rays 22-25; pectoral-fin rays 12-13; pelvic-fin rays 5-6.

Scales large and cycloid. Body and head entirely scaled, except ventral surface of head. One row of scales on anal-fin base, no scales on dorsal-fin base, and three rows of scales on caudal-fin base. Frontal squamation usually F-patterned, rarely G or H- patterned; E-scales slightly overlapping medially; scales arranged in transverse pattern. Longitudinal series of scales 26-27, scales regularly arranged in younger specimens, 30-31 and irregularly arranged in older specimens; transverse series of scales 13-15; scale rows around caudal peduncle 16-18. Minute contact organs on scales of flank in males. Rows of minute contact organs on two or three uppermost pectoral-fin rays. No contact organ on anal, dorsal and caudal fins.

Cephalic neuromasts: supraorbital 19-21, parietal 3, anterior rostral 1, posterior rostral 1, infraorbital 2 + 25-26, preorbital 3, otic 3-4, post-otic 3-4, supratemporal 1, median opercular 1, ventral opercular 2-3, preopercular 21-23, mandibular 14-15, lateral mandibular 5.

Basihyal nearly triangular, width about 55% of length; basihyal cartilage long, about 60% of total basihyal length, with pronounced lateral projection. Six branchiostegal rays. Two teeth on second pharyngobranchial. Gill-rakers on first branchial arch 3 + 11. Dermosphenotic ossification absent. Ventral process of posttemporal short. Total vertebrae 29-31.

Coloration

Males: sides of body light bluish green, with 7-11 black bars; anteriormost bars often nearer among themselves than posterior bars; bars narrow, interspace about 2-5 times wider than bars. Urogenital papilla dark gray. Sides of head light bluish green to blue on opercular and infraorbital regions; black infraorbital bar, wider close to eye, gradually narrowing ventrally; elongate black supraorbital bar, extending over neuromast parietal series. Iris dark yellow, with dark brown bar through center of eye. Dorsal and anal fins greenish gray, with light blue bars, more conspicuous in preserved specimens, and vertically elongated bluish black spot. Caudal fin greenish gray, with light blue elongate spots on basal portion. Pelvic fins greenish gray. Pectoral fins hyaline, with black ventral margin.

Females: sides of body light yellowish brown, usually with pale gray bars, sometimes vertical rows of elongate dark gray spots; venter pale golden; no black spot on anterocentral portion of flank; two black spots vertically arranged on posterior portion of caudal peduncle, sometimes coalesced to form an 8-shaped spot. Opercular region pale greenish blue. Iris light yellow, with gray bar through center of eye. Infraorbital and supraorbital bars dark gray. Unpaired fins gray, with light gray elongate spots parallel to fin rays on basal portion, more conspicuous on dorsal and anal fins and forming short bars; paired fins hyaline.

Distribution

Known only from the lower río Tacuarí floodplains, laguna Merin basin, eastern Uruguay (Fig. 52).

Etymology

Named in honor of Heber Salvia, the first collector of the new species, in recognition of his contributions to field studies on Uruguayan annual fishes for more than 15 years.