Simpsonichthys rosaceus

Wilson J. E. M. Costa, 2007, Taxonomic revision of the seasonal South American killifish genus Simpsonichthys (Teleostei: Cyprinodontiformes: Aplocheiloidei: Rivulidae)., Zootaxa 1669, pp. 1-134 : 22-25

Simpsonichthys rosaceus Costa, Nielsen & De Luca, 2001

(Figs. 11-12)

Simpsonichthys rosaceus Costa, Nielsen & De Luca, 2001: 28 ( type locality: temporary pool near rio Pardo, road between Potiguara [ Potiragua ] and Itapetininga , Estado da Bahia, Brazil [approximately 15°30’S 39°50’W; altitude about 170 m]; holotype: MZUSP 62572 ).

Material examined

Brazil: Estado da Bahia: MZUSP 62572 , holotype, male, 29.6 mm SL; MZUSP 62573 , 5 paratypes; UFRJ 5146 , 20 paratypes; UFRJ 5147 , 4 paratypes (c&s); temporary pool close to rio Pardo, road between Potiguara and Itapetinga ; A. C. De Luca, D. S. U. Martins & V. S. Favalli, 23 Jun. 2000. UFRJ 5289 , 46; same locality ; W. J. E. M. Costa, C. P. Bove & B. B. Costa, Jan. 2001.

Diagnosis

Similar to S. bokermanni and S. perpendicularis , and distinguished from other species of the Ophthalmolebias group by having pale golden bars restricted to anterior portion of flanks in males (vs. golden bars absent in S. constanciae , and bright greenish blue bars on the whole flank in S. suzarti ). Similar to S. perpendicularis and distinguished from S. bokermanni by the absence of bright dots on the flanks and unpaired fins in males (vs. bright dots on dorsal fin, dorsal portion of caudal fin, and dorsal portion of flanks). Distinguished from S. perpendicularis in having pale red to pink unpaired fins (vs. yellow) and the absence of three brown stripes on the posterior portion of flanks (vs. presence).

Description

Morphometric data appear in Table 1. Largest specimen examined 29.6 mm SL. Dorsal profile weakly concave on head, convex from nape to end of dorsal-fin base, nearly straight on caudal peduncle. Ventral profile convex from lower jaw to end of anal-fin base, nearly straight on caudal peduncle. Body moderately deep, compressed, greatest body depth at level of pelvic-fin base. Eye positioned on lateral portion of head side. Snout blunt to slightly pointed. Urogenital papilla cylindrical and short in males, pocket-shaped in females.

Tip of both dorsal and anal fins slightly pointed in males, rounded in females. Tip of both dorsal and anal fins with filamentous rays in males, the dorsal-fin filaments reaching vertical through middle of caudal fin, tip of anal-fin filaments reaching vertical through base of caudal fin. Dorsal-fin rays unbranched. Caudal fin rounded. Pectoral fins elliptical. Posterior margins of pectoral fins reaching vertical through base of 4th analfin ray in males and between pelvic-fin base and anus in females. Tip of each pelvic fin reaching base of 3rd anal-fin ray in males and between urogenital papilla and anal-fin origin in females. Pelvic-fin bases medially in close proximity. Dorsal-fin origin on vertical through base of 6th or 7th anal-fin ray, between neural spines of vertebrae 11 and 12 in males, and between neural spines of vertebrae 12 and 13 in females. Anal-fin origin between pleural ribs of vertebrae 7 and 8 in males, and between pleural ribs of vertebrae 8 and 9 in females. Dorsal-fin rays 15-18 in males, 13-15 in females; anal-fin rays 22-24 in males, 19-22 in females; caudal-fin rays 23-25; pectoral-fin rays 12-13; pelvic-fin rays 5-6.

Frontal squamation E-patterned; E-scales overlapping medially; no scale anterior to H-scale; supraorbital scales 1-2. Longitudinal series of scales 25-27; transverse series of scales 8-9; scale rows around caudal peduncle 14. Minute contact organ on each scale of anteroventral half of body side in males. Small, papillate contact organs on medial surface of dorsalmost pectoral-fin ray in males.

Cephalic neuromasts: supraorbital 7-8 + 5-6, parietal 2-3, anterior rostral 1, sometimes absent, posterior rostral1, infraorbital 2 + 18-25, preorbital 3, otic 2, post-otic 3, supratemporal 1, median opercular 1, ventral opercular 2-4, preopercular 17-18, mandibular 12, lateral mandibular 3, paramandibular 1. One or two neuromasts on center of each scale of lateral line. Two neuromasts on caudal-fin base.

Basihyal subtriangular, width about 40% of length; basihyal cartilage about 20% of total length of basihyal. Six branchiostegal rays. Second pharyngobranchial teeth 2-3. Gill-rakers on first branchial arch 3-4 + 11. Vomerine teeth absent. Dermosphenotic present. Ventral process of posttemporal long. Total vertebrae 26-28.

Coloration

Males. Sides of body light pink, venter pale golden; three or four faint pinkish gray bars alternated with pale golden bars on anterior portion of flanks (in preserved specimens, ten bars between head and caudal peduncle); sometimes faint purplish gray stripe on lateral midline of caudal peduncle. Opercular region golden. Iris yellow, with purplish brown bar through center of eye. Dorsal fin yellow with round reddish gray spots on basal half, dark pink on distal half. Caudal fin pale red to pink, with small yellow and gray spots. Anal fin pale red to pink, with faint gray spots, and pale yellow base. Pectoral fins hyaline. Pelvic fins pink.

Females. Sides of body pale brown, with 12-15 dark gray bars between head and caudal-fin base; usually one or two black blotches on anterocentral portion, sometimes absent, when present alternating with light greenish blue short bars. Opercular region pale golden. Iris yellow, with gray brown bar through center of eye. Dorsal fin hyaline, with dark gray round spots. Caudal fin hyaline, pale pink on ventral portion. Anal fin pink, with faint blue spots. Paired fins hyaline.

Distribution

Known only from the type locality, middle rio Pardo basin, Estado da Bahia, northeastern Brazil (Fig. 4).

Habitat

Known only from a temporary pool in the border of the Atlantic forest, located in the narrow floodplain of the rio Pardo.