Lysmata vittata ( Stimpson, 1860 )

Alves, Douglas Fernandes Rodrigues, Lima, Daniel José Marcondes, Hirose, Gustavo Luis, Martinez, Pablo Ariel, Dolabella, Silvio Santana & Barros-Alves, Samara De Paiva, 2018, Morphological and molecular analyses confirm the occurrence of two sympatric Lysmata shrimp (Crustacea, Decapoda) in the southwestern Atlantic, Zootaxa 4526 (1), pp. 41-55 : 47-48

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).

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.

Figures

FIGURE 1. Lateral view of (A) Lysmata lipkei Okuno & Fiedler, 2010 and (B) Lysmata vittata (Stimpson, 1860), from the Vaza-Barris estuary, Sergipe, Brazil. Scale bar: 5.0 mm. Photographs by DFR Alves.

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.

FIGURE 4. Phylogenetic tree of genus Lysmata (Risso, 1816), including Lysmata lipkei Okuno & Fiedler, 2010 and Lysmata vittata (Stimpson, 1860) from Brazil, constructed via Maximum Likelihood analysis of the 16S DNA gene. Numbers are support values for 1000 bootstraps; values <50% were not included.