Navanax gemmatus (Mörch, 1863)

Delgado, Marlon, Freire, Fúlvio Aurélio de Morais, Meirelles, Carlos Augusto Oliveira de, Padula, Vinicius, Bahia, Juliana & Brandão, Simone Nunes, 2022, Sea slugs (Gastropoda: Heterobranchia) from Rio Grande do Norte, Northeastern Brazil, Papéis Avulsos de Zoologia 62, pp. 1-26 : 6-7

05. Navanax gemmatus (Mörch, 1863) ( Fig. 2E )

Material examined: Parrachos de Maracajaú, Maxaranguape , 17.V.2015, one specimen, 40 mm (body length), leg. M. Delgado ( GEEFAA 1322 ) ; Praia de Santa Rita, Extremoz, 28.III.2009, one specimen, 40 mm (body length),leg. V. Padula ( MZSP97068 ), 24.VI.2009, one specimen, 28 mm (body length),leg. M. Delgado ( GEEFAA 319 ). Praia de Pirambúzios,Nísia Floresta, 14.IV.2010, one specimen, 20 mm (body length), leg. G.Grimaldi ( GEEFAA 300 ), 29.I.2014, one specimen, 45 mm (body length), leg. T.Accioly ( GEEFAA 328 ), 15.V.2014, one specimen, 30 mm (body length), phot. reg. T. Accioly .

Description: Elongated and cylindrical body. Predominant body color greenish-brown, with numerous dorsal, thin longitudinal lines beige color. Cephalic shield well elongated and rounded at the anterior end, well-developed retractable eyes, a pair of lateral lobes and a well-developed mouth structure. Lateral parapodia covering 80% of the dorsum, leaving a small part exposed. In the posterior region, terminal lobes divided into two semicircular flaps, forming a robust tail.

Geographic distribution: Western Atlantic: Antigua & Barbuda, Aruba Bahamas, Barbados, Belize, Bonaire, Chile, Colombia, Costa Rica, CuraÇao, Grenada, Guadeloupe, Honduras, Jamaica, Martinique, Mexico, St. Barthelemy / St. Bartholomew, St. Vicent & the Grenadines, USA, Venezuela, Virgin Islands, Brazil (Pernambuco, Rio de Janeiro, Rio Grande do Norte – present study, São Paulo) ( Valdés et al., 2006; García et al., 2008; Rios, 2009;OrnelasGatdula et al., 2012).

Remarks: Our specimens were initially identified as Navanax aenigmaticus Bergh, 1893 , however OrnelasGatdula et al. (2012) performed a phylogenetic analysis where they revealed a complex of three species under the name N. aenigmaticus . This species complex showed genetic and morphological differences between specimens from the eastern Pacific, western and eastern Atlantic. The species present in the western Atlantic is N. gemmatus .

Figures

Figure 2. Heterobranch sea slugs from Rio Grande do Norte. (A) Micromelo undatus (15 mm – GEEFAA 294); (B) Haminoea antillarum (2 mm – GEEFAA 344); (C)Camachoaglaja berolina(7 mm– GEEFAA270);(D)Chelidonurahirundinina(16mm– GEEFAA1320);(E)Navanaxgemmatus (40mm– MZSP97068);(F)Ascobulla ulla (7 mm – MZSP 97049); (G) Oxynoe antillarum (25 mm – GEEFAA 352); (H) Elysia canguzua (15 mm – GEEFAA 295); (I) Elysia pawliki (25 mm – MZSP 97061); (J) Elysia subornata (14 mm – MZSP 97050); (K) Thuridilla malaquita (15 mm – phot. reg.); (L) Caliphylla mediterranea (9 mm – GEEFAA 349); (M) Aplysia cervina (70mm – MZSP 97074); (N) Aplysia dactylomela (76 mm – MZSP 97073);(O) Bursatellaleachii (75 mm – GEEFAA 324).