Simpsonichthys magnificus

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 : 91-93

Simpsonichthys magnificus (Costa & Brasil, 1991)

(Figs. 59)

Cynolebias magnificus Costa & Brasil, 1991: 59 ( type locality: right bank plain of the rio Sao Francisco, about 1 km from the river channel , county of Manga, Minas Gerais, Brazil [about 13°40’S 43°50’W]; holotype: MZUSP 41374 ).

Material examined

Brazil: Estado de Minas Gerais, rio São Francisco basin: MZUSP 41374 , holotype, male, 26.8 mm SL; MZUSP 41375 , 9 paratypes; UFRJ 154 , 12; UFRJ 260 , 1 (c&s); UFRJ 2119 , 1 (c&s); Manga, right bank plain of the rio Sao Francisco, about 1 km from the river channel ; G. C. Brasil, 10 Feb. 1990. UFRJ 4959 , 4; UFRJ 4958 , 3 (c&s); 1 km E from Gado Bravo, rio Verde Grande floodplains ; W. J. E. M. Costa, F. Pupo & E. Araujo, 10 Feb. 1999. Estado da Bahia: UFRJ 5827 , 1; Malhada ; D. Nielsen & A. Carletto, Feb. 2002. MNRJ 16116 , 10; Mocambinho, Manga ; D. F. Moraes, L. O. Alvarenga & C. Rico, 1990. MNRJ 16324 , 8; Mocambinho, Manga ; D. F. Moraes & J. A. Oliveira, 1990.

Diagnosis

Similar to S. picturatus and S. carlettoi and distinguished from all other species of the S. magnificus group by having pectoral fins red in males (vs. hyaline). Similar to S. picturatus and distinguished from remaining species of the S. magnificus group by possessing distal border of the unpaired fins black in males (vs. never a black border), dorsal and anal fins rounded in males and without filamentous rays in males (vs. pointed, with filamentous rays on the tip); differs from S. picturatus in having five to seven red bars on anterior portion of flank in males (vs. eight to ten), 13-15 bars on flank in females (vs. 18-20), and greenish blue vermiculate transverse stripes on unpaired fins in males (vs. greenish blue dots).

Description

Morphometric data appear in Table 5. Largest specimen examined 38.1 mm SL. Dorsal profile convex from snout to end of dorsal-fin base, approximately 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 dorsal portion of side of head. Snout blunt. Urogenital papilla cylindrical and short in males, pocket-shaped in females.

Tip of dorsal and anal fins rounded in both sexes; fin filaments absent. Dorsal-fin rays unbranched. Caudal fin rounded. Pectoral fins elliptical. Posterior margin of each pectoral fin reaching vertical through base of 6th or 7th anal-fin ray in males, and through base of 2nd or 3rd anal-fin ray in females. Tip of each pelvic fin reaching base of 2nd or 3rd anal-fin ray. Pelvic-fin bases in close proximity. Dorsal-fin origin slightly anterior or slightly posterior or on vertical through anal-fin origin in males, and between base of 3rd and 5th anal-fin ray in females; dorsal-fin origin between neural spines of vertebrae 6 and 8 in males and neural spines of vertebrae10 and 11 in females. Anal-fin origin between pleural ribs of vertebrae 7 and 8 in males and pleural ribs of vertebrae 8 and 9 in females. Dorsal-fin rays 21-25 in males, 15-18 in females; anal-fin rays 21-23 in males, 18-20 in females; caudal-fin rays 23-25; pectoral-fin rays 12-13; pelvic-fin rays 5-6.

Frontal squamation E-patterned; E-scales slightly overlapping medially; no row of scales anterior to G- scale; single supraorbital scale. Longitudinal series of scales 26-28; transverse series of scales 9; scale rows around caudal peduncle 12. Contact organ on each scale of ventral portion of lateral surface of body in males. Small papillate contact organs on inner surface of dorsalmost ray of pectoral-fin in males. Cephalic neuromasts: supraorbital 10-11, parietal 4, anterior rostral 1, posterior rostral 1, infraorbital 3 + 21, preorbital 4, otic 2, post-otic 2, supratemporal 1, median opercular 1, ventral opercular 2, preopercular 16, mandibular 12, lateral mandibular 4-5, paramandibular 1. One neuromast on each scale of lateral line. Two neuromasts on caudal-fin base.

Basihyal subtriangular, width about 65% of length; basihyal cartilage about 25% of total length of basihyal. Six branchiostegal rays. Second pharyngobranchial teeth 1-2. Gill-rakers on first branchial arch 3 + 10. Vomerine teeth absent. Dermosphenotic absent. Ventral process of posttemporal long. Total vertebrae 26-28.

Coloration

Males. Sides of body dark yellow ochre on anterior half, dark purplish pink on posterior half of flank; five to seven red bars, three anterior red bars alternating with three dark green bars, and wider and more conspicuous than posterior bars; vertically elongated, minute metallic blue spots on flank, more conspicuous on its posterior half; venter light yellow ochre. Sides of head side yellow ochre, golden with blue small spots on opercular region; scales of posterodorsal portion of head side with red margin. Iris light yellow, with dark reddish brown bar through center of eye. Unpaired fins dark red with transverse greenish blue vermiculate marks; distal margin dark gray to black. Pectoral fins red, ventral margin gray to black. Pelvic fins dark red.

Females. Sides of body light purplish gray, with 13-15 pale greenish gray interrupted bars, anterior bars extremely narrow; venter pale orangish golden; one to four rounded dark greenish gray blotches on anterocentral portion of flank. Opercular region pale golden. Iris light yellow, with gray bar through center of eye. Fins hyaline; small light blue spot on posterior margin of anal fin, just posterior to fin base.

Distribution

Middle rio São Francisco basin, between Malhada, Estado da Bahia, and Itacarambi, Estado de Minas Gerais, Brazil (Fig. 1).

Habitat

Shaded places of temporary pools in the Caatinga.