Morphological and molecular analyses confirm the occurrence of two sympatric Lysmata shrimp (Crustacea, Decapoda) in the southwestern Atlantic Author Alves, Douglas Fernandes Rodrigues Author Lima, Daniel José Marcondes Author Hirose, Gustavo Luis Author Martinez, Pablo Ariel Author Dolabella, Silvio Santana Author Barros-Alves, Samara De Paiva text Zootaxa 2018 2018-11-28 4526 1 41 55 journal article 27901 10.11646/zootaxa.4526.1.3 3ca9acbb-9081-42c7-880c-5847a55c42a6 1175-5326 2611393 956F660E-8F02-45EA-8342-3A92566DC3DB Lysmata vittata ( Stimpson, 1860 ) ( Figs. 1B , 3 ) Hippolysmata vittata Stimpson, 1860 : 26 . Nauticaris unirecedens Spence Bate, 1888 : 608 , plate 110, fig. 1 Hippolysmata vittata var. subtilis Thallwitz, 1892 : 22 . Hippolysmata durbanensis Stebbing, 1921 : 20 , plate 5. Material examined . Brazil , Sergipe : 7 hermaphrodites ( MZUSP 37419 ), Aracaju , Orla do Mosqueiro , D.F.R . Alves coll., i.2016 ; 10 hermaphrodites, 3 intermediaries ( MZUSP 37420 ), same collection data, 17.i.2017 ; 1 hermaphrodite ( MZUSP 37514 ), Orla do Mosqueiro , D.F.R . Alves coll., ii.2017 . Additional material . 1 hermaphrodite (MZUSP 32296), Brazil , São Paulo , Enseada de Ubatuba, Ubatuba, Radial V, 19.v.1996 . Distribution . Widely distributed in the Indo-West Pacific, from Africa to the Philippines , Japan , Russia , Australia , and New Zealand ( Chace 1997 ; Ahyong 2010 ; Marin et al. 2012a ); Mediterranean Sea ( Abdelsalam 2018 ) and Western Atlantic: Brazil ( Sergipe , Bahia , Rio de Janeiro , and São Paulo ) ( Soledade et al. 2013 ; Terossi et al. 2018 ; present study). FIGURE 3. Lysmata vittata (Stimpson, 1860) . (A) frontal region, dorsal; (B) frontal region, lateral; (C) left antennule; (D) right second pereiopod; (E) right fifth pereiopod; (F) right dactylus of fifth pereiopod. (A–F) Hermaphrodite shrimp 5.3 mm CL (MZUSP 37514). Scale bars: A–B, 1.0 mm; C–F, 0.5 mm. Morphological variation. Straight rostrum, not overreaching the antennular peduncle ( Fig. 3A,B ). Rostrum with 6–7 dorsal teeth (predominantly 7) and 2–4 ventral teeth (predominantly 3) ( Fig. 3A,B ). Antennular peduncle with 1 minute spinule on the third article ( Fig. 3C ). Accessory branch of dorsal antennular flagellum with 1 unguiform segment, eventually rudimentary ( Fig. 3C ). Merus of the second pereiopod subdivided into 6–9 articles ( Fig. 3D ). Carpus of the second pereiopod subdivided into 15–18 articles ( Fig. 3D ). Merus of the fifth pereiopod with 1–4 spiniform setae ( Fig. 3E ). Dactylus of the fifth pereiopod biunguiculate, with tufts of setae on terminal margin, armed with 4 small spines on posterior margin ( Fig. 3F ). Phylogeny. The two sequences obtained for L. lipkei from Sergipe State ( Brazil ) were a close match (p distance <0.001), and formed a well-supported clade with the sequence of a L. lipkei specimen from Japan ( Fig. 4 ). The genetic divergence among these three L. lipkei specimens varied from 0 to 0.018 (p distance). Phylogenetic analyses (ML and Bayesiana Inference) placed L. lipkei on the outside of the Lysmata - Exhippolysmata clade, a result well supported by values of more than 90% and 1 for bootstrap and posterior probability support, respectively ( Fig. 4 , S 1 ). The two sequences obtained for L. vittata specimens from Sergipe State ( Brazil ) were a close match (p distance <0.001). These two sequences did not segregate together in a single clade but instead clustered together with four other sequences from specimens of L. vittata (two sequences of specimens from Thailand , and two specimens from Bahia State, Brazil ), inside a Morpho-variable clade ( Fig. 4 ). The genetic divergence among these six specimens of L. vittata varied from 0 to 0.008 (p distance). The interspecific genetic divergences estimated among species in the Lysmata - Exhippolysmata clade ranged from 0.043 to 0.226 (p distance). The lowest values (0.043) were found between Lysmata amboinensis (de Man, 1888 ) and Lysmata grabhami ( Gordon, 1935 ) , which were the closest inside the Cleaner clade in the phylogenetic analyses ( Fig. 4 ). The intraspecific genetic divergence (Atlantic vs. Indo-Pacific specimens) of L. lipkei and L. vittata was much lower (<0.018) than the interspecific genetic divergence inside Lysmata - Exhippolysmata clade.