Pseudorhombila octodentata Rathbun, 1906

Pseudorhombila octodentata Rathbun, 1906 View in CoL

( Figs. 1A–E View Figure 1 , 4A–B View Figure 4 , 5 View Figure 5 )

Pseudorhombila octodentata Rathbun, 1906: 91 View in CoL . — Rathbun, 1918: 43, figs. 17, 18, pl. 14. — Chace, 1940: 48. — Guinot, 1969a: 704, figs. 113–115, pl. 3, fig. 2. — Gómez and Ortiz, 1976: 9 (in list). — Hernández Aguilera, 1982: 2, figs. 1A, 2A, 3A, 4A, 5A, 6A. — Coelho and Coelho-Filho, 1993: 560 (in list). — Martínez-Iglesias and Gómez, 1994: 26, figs. 1–3. — Hendrickx, 1995: 14, figs. 1A, 2A, 3D. — Melo, 1996: 413. — Boschi, 2000: 122 (in list). — Melo, 2010: 47 (in list). — Boos et al. 2012: 1026 (in list). Material examined. 1 male (CL = 50.7 mm; CW = 40.13 mm), Revizee/NE (Cruzeiro 3), R/V Natureza col., Sergipe, Station #3, (10°41’S 36°19’W), 27 October 2000, 130 m, gravel bottom, MOUFPE: 19993.

Geographic distribution. Western Atlantic: Cuba (Punta Alegre), Lesser Antilles, Dominica, and Brazilian states of Sergipe (present record), Rio de Janeiro, São Paulo, and Rio Grande do Sul ( Melo, 1996; 2010; Boos et al., 2012) ( Fig. 5 View Figure 5 ).

Remarks. The characteristics of the examined material were consistent with the original description provided by Rathbun(1906) and additional taxonomic information provided by Guinot (1969a) and Hernández Aguilera (1982) for specimens collected in the islands of Central America. Pseudorhombila octodentata differs from the other species occurring in Brazil ( P. quadridentata ) in the following characters: antero-lateral margin with four teeth (vs. two teeth in P. quadridentata ) ( Figs. 1A View Figure 1 ; 2A View Figure 2 ); ocular peduncle with acute lateral granules (vs. less pronounced in P. quadridentata ); the external surface of the third maxilliped is granulated(vs. smooth or little granulated in P. quadridentata ) ( Figs. 1C View Figure 1 ; 2C View Figure 2 ); merus of the third ambulatory legs with strong and acute spines (vs. granulated in P. quadridentata ); the first and second pleonal somites are corrugated (vs. only the first pleonal somite is corrugated in P. quadridentata ) ( Figs. 1D View Figure 1 ; 2D View Figure 2 ); well-developed gonopod 1 (G1), convergent at midline of thoracic sternum, slightly curved, and with few spines at the tip (vs. strongly curved, with several spines at the tip,and showing an apex elevation in P. quadridentata ) ( Fig. 4A–D View Figure 4 ) (see more details in Guinot, 1969a; Hernández Aguilera, 1982). Pseudorhombila octodentata presents a similar geographic distribution to that of P. quadridentata ( Fig. 5 View Figure 5 ), although P. octodentata does not occur in the Gulf of Mexico, only in the South and Southwest regions of Brazil (see P. octodentata distribution topic).However, considering the vertical distribution, P. quadridentata occurs more commonly in shallow waters (between 20 and 64 m) (see remarks under P. quadridentata ), and P. octodentata has a bathymetric distribution between 180 and 329 m ( Chace, 1940; Gómez and Ortiz, 1976; Martínez-Iglesias and Gómez, 1994). The examined specimen was found at 130 m, thus providing a new shallow record for this species. It is also the first record of this species in the Northeast region of Brazil.