Phalloceros aspilos, Lucinda, 2008

Lucinda, Paulo Henrique Franco, 2008, Systematics and biogeography of the genus Phalloceros Eigenmann, 1907 (Cyprinodontiformes: Poeciliidae: Poeciliinae), with the description of twenty-one new species, Neotropical Ichthyology 6 (2), pp. 113-158 : 128-129

Phalloceros aspilos , new species

Figs. 19 , 20

Phalloceros sp. n. G Lucinda & Reis (2005).

Holotype. MNRJ 23607, rio Parati-Mirim, near km 202 of road BR 101, upstream Vila do Patrimônio, approximately 23 o 14’S 44 o 38’W, Rio de Janeiro, Brazil, 29 Jan 1989, H. São Thiago et al.

Paratypes. BRAZIL. Rio de Janeiro. MCP 30509, 6/2* ; and MNRJ 11727, 7, collected with the holotype. MCP 20594, 7, Parati, creek affluent to rio Parati-Mirim, near km 207 of BR 101, road from Parati to Ubatuba, 23 º 20’28"S 44 º 44’45"W, 22 Jan 1997, J.F.P. Silva et al. MCP 31350, 36, Parati, small stream affluent to rio Carapitanga ca. 1.4 km from road BR 101, 23 º 17’52"S 44 º 42’37"W, 17 Oct 2002, V.A. Bertaco et al.

Diagnosis. Phalloceros aspilos can be diagnosed by the following uniquely derived autapomorphy: hypural plate almost bipartite, with very large aperture [131-3*]. Furthermore, P. aspilos is readily distinguished from its congeners, except P. tupinamba and P. leptokeras by (1) the presence of a lateral ramus of the female urogenital papilla; (2) female urogenital papilla left turned; (3) large sickle like hook on the gonopodial appendix located in its inner surface and close to its base ( Fig. 20 ); and (4) absence of inconspicuous vertical bars along body sides ( Fig. 19 ). Phalloceros aspilos can be distinguished from P. leptokeras and P. tupinamba by the absence of lateral spot. Phalloceros aspilos can also be distinguished from P. tupinamba by the predorsal length of males (54.8-56.3 vs. 57.5-59.7 % SL, respectively).

Description. Morphometric data in Tables 5 and 6 . Range of SL: 25.8 to 38.3 mm (females), 22.2 to 23.8 mm (males). Dorsal-fin rays: 7 [2], 8* [14]. Branched pectoral-fin rays: 6 [3], 7* [10]. Pelvic-fin rays: 5* [3] (males), 5 [13] (females).Anal-fin rays of females: 10 [2], 11 [11].Anal-fin rays of males: 9* [3]. Branched caudal-fin rays: 12* [10], 13 [3], 14 [2]. Predorsal scales: 14 [7], 15 [3]. Longitudinal series of scales: 28 [1], 29 [10], 30* [4]. Series of scales around caudal peduncle: 16* [16]. Transverse series of scales: 7* [16]. Serrae on R4p: 13 [2], 15* [1]. Epipleural ribs: 12 [1]. Pleural ribs: 15 [1]. Vertebrae: 33 [1]. Female urogenital papilla slightly left turned and with lateral ramus. Hooks of gonopodial appendix large and sickle like ( Fig. 20 ).

Color in alcohol. Eye greyish iridescent black with greenish brown pupil. Ground color cream, darker in upper half. Border of scales and subjacent skin replete with brown chromatophores, more concentrated at short distance from scale border, conferring reticulate pattern to body sides, mainly on upper half. Brown chromatophores scattered through whole body, more concentrated on dorsal portion, mainly on head, snout, opercle, and ventral surface of mandible. No lateral spot. Dorsal-fin membrane hyaline, except for faint band of chromatophores on distal border of dorsal fin and near dorsal-fin base. Pectoral, pelvic, and caudal fins hyaline. Dark brown line along R3. Anal fin of females hyaline; chromatophores scattered through first three rays and forming patch of dark pigmentation.

Etymology. From the Greek, ασπιλος, −ον, [ = aspilos , -on], adj. m. nom. sg., stainless, without spots, spotless; alluding to the absence of the lateral spot. An adjective.

Distribution. Rio Parati-Mirim, Rio de Janeiro ( Fig. 18 ).

Figures

Fig. 19. Phalloceros aspilos. (A) Holotype, male, 23.6 mm SL, MNRJ 23607, rio Parati-Mirim, near km 202 of road BR 101, upstream Vila do Patrimônio; (B) paratype, female, MCP 30509, 33.7 mm SL, collected with the holotype.

Fig. 20. Gonopodium tip of Phalloceros aspilos, MCP 30509. R3, R4a,R4p,R5a,R5pindicate gonopodial rays.Scale bar 1mm.

Fig. 18. Collection localities of Phalloceros elachistos (fivepointed star, 1), P. leptokeras (triangle, 2), P. aspilos (circle, 3), P. alessandrae (inverted triangle, 4), and P. megapolos (square, 5). Some symbols represent more than one lot or locality. Numbers represent type localities. The inset is the range of the genus.