Simpsonichthys carlettoi

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 : 89-91

Simpsonichthys carlettoi Costa & Nielsen, 2004

(Figs. 58)

Simpsonichthys carlettoi Costa & Nielsen, 2004: 126 ( type locality: temporary pool near Guanambi, road to Malhada , Estado da Bahia, Brazil, 14°13.989’S 42°57.667’W, altitude about 500 m; holotype: MCP 34089 ).

Material examined

Brazil: Estado da Bahia, rio São Francisco basin: MCP 34089 , holotype, male, 30.9 mm SL; UFRJ 5945 , paratypes, 1 male, 35.4 mm SL, and 1 female, 27.2 mm SL (c&s); temporary pool near Guanambi, road to Malhada , 14° 13.989’S 42° 57.667’W, rio das Rãs drainage; altitude about 500 m; A. Carletto & D. T. Nielsen, Jan. 2002. UFRJ 5946 , paratype, 1 male, 33.3 mm SL; born in aquarium, first generation obtained from the three wild type specimens . UFRJ 6065 , 5; Guanambi, road to Malhada ; W. J. E. M. Costa, C. P. Bove & B. B. Costa, 13 Jan. 2005. UFRJ 6070 , 11; UFRJ 6071 , 3; 14 km from Guanambi, road to Malhada ; W. J. E. M. Costa, C. P. Bove & B. B. Costa, 13 Jan. 2005.

Diagnosis

Similar to S. magnificus and S. picturatus and distinguished from all other species of the S. magnificus group by having pectoral fins red in males (vs. hyaline). Distinguished from S. magnificus and S. picturatus by possessing dorsal and anal fins pointed in males (vs. rounded) and distal border of unpaired fins not distinctively pigmented in males (vs. unpaired fins with black border). It is also distinguished from S. magnificus by never having blue spots of the dorsal fin coalesced to form transverse vermiculate marks in males (vs. coalesced), and from S. picturatus by having more dorsal-fin rays in males (24-25, vs. 19-23).

Description

Morphometric data appear in Table 5. Largest specimen examined 35.4 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 head side. Snout blunt. Urogenital papilla cylindrical and short in males, pocket-shaped in females.

Tip of dorsal and anal fins pointed in adult males to sharply pointed in older males, rounded in females. Dorsal-fin rays unbranched. Caudal fin rounded. Pectoral fins elliptical. Posterior margin of each pectoral fin reaching vertical through base of 6th anal-fin ray in males and anus in females. Tip of each pelvic fin reaching base of 3rd anal-fin ray in males and urogenital papilla in females. Pelvic-fin bases in close proximity. Analfin origin on vertical posterior to dorsal-fin origin in males, anal-fin origin on vertical through base of fourth dorsal-fin ray; dorsal-fin origin on vertical posterior to anal-fin origin in females, through base of fourth analfin ray. Dorsal-fin origin between neural spines of 6th and 7th vertebrae in males, and between neural spines of 10th and 11th vertebrae in females. Anal-fin origin between pleural ribs of 7th and 8th vertebrae in males, and between pleural ribs of 9th and 10th vertebrae in females. Dorsal-fin rays 24-25 in males, 15-18 in females; anal-fin rays 21-24 in males, 18-20 in females; caudal-fin rays 22-23; pectoral-fin rays 13; pelvic-fin rays 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; transverse series of scales 10; scale rows around caudal peduncle 16. Contact organ on each scale of ventral portion of opercle and lateral surface of trunk in males. Papillate contact organs on inner surface of dorsalmost pectoral-fin ray in males. Cephalic neuromasts: supraorbital 10-11, parietal 3, anterior rostral 1, posterior rostral 1, infraorbital 2 + 20- 21, preorbital 3, otic 2, post-otic 2-3, supratemporal 1, median opercular 1, ventral opercular 1-2, preopercular 16 -18, mandibular 11-12, lateral mandibular 3, paramandibular 1. One or two neuromast on each scale of lateral line. Two neuromasts on caudal-fin base.

Basihyal subtriangular, width about 55% of length; basihyal cartilage about 25% of total length of basihyal. Six branchiostegal rays. Second pharyngobranchial teeth 2-3. Gill-rakers on first branchial arch 3 + 10. Vomerine teeth absent. Dermosphenotic absent. Ventral process of posttemporal long. Total vertebrae 27.

Coloration

Males. Sides of body dark brownish purple, with 10 or 11 red bars; three anterior red bars wider and more conspicuous than posterior bars, and alternating with three dark green bars; minute vertically-elongated, metallic blue spots on entire flank, brighter on posterior half; venter light gray. Sides of head light blue, with pale red bar on preopercle. Iris light yellow, with dark reddish brown bar through center of eye. Unpaired fins dark red, with transverse rows of bright greenish blue dots; dots on caudal fin and posterior portion of anal fin coalesced to form vermiculate marks. Pectoral and pelvic fins red.

Females. Side of body light purplish gray, with gray spots on anterior portion and seven interrupted bars on posterior portion of flank; five rounded black blotches on anterocentral portion of flank, three of them large, about equal eye in size. 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.

Distribution

Rio das Rãs drainage, rio São Francisco basin, Estado da Bahia, north-eastern Brazil (Fig. 4).

Habitat

Temporary pools in the Caatinga.