Lysmata arvoredensisnov. sp. a new species of shrimp from the south coast of Brazil with a key to species ofLysmata(Caridea: Lysmatidae) recorded in the southwestern Atlantic

Abstract

Lysmata arvoredensis sp. nov. inhabits temperate waters in the south coast of Brazil and is named in tribute to the Marine Protected Area REBIO Arvoredo. This is the fourth species belonging to the genus Lysmata recorded for the region and the ninth for Brazil. L. arvoredensis sp. nov. can be distinguished from other species of Lysmata by the presence of a nearly completely fused accessory branch with a single free unguiform segment on the outer antennular flagellum; a rostrum with seven dorsal (2+5) and three ventral teeth; a stylocerite with a pointed tip bearing mesial setae; a second pereiopod with 22–24 carpal subsegments and 14–16 subsegments in the merus; a merus of the third pereiopod with five ventrolateral and 12 ventral spines on the propodus; and its color pattern, with red bands and patches in pleonites 2–3 that resemble a mask in dorsal view. Molecular characters demonstrate that L. arvoredensis sp. nov. is most closely related to other species of Lysmata belonging to the Neotropical and Cleaner clades. To support future ecological studies in the region, identification keys to the species of Lysmata recorded in the southwestern Atlantic Ocean are provided.

Atlantic expansion of the African caridean shrimp Lysmata uncicornis Holthuis & Maurin, 1952 (Caridea: Lysmatidae)

“…The same authors referred that the second pereiopod of L. arvoredensis shows 11-16 subsegments in the merus and 22-24 subsegments in the carpus, in the range of L. uncicornis 11-14 and 19-28 articles, respectively, (Holthuis and Maurin 1952), and in specimens collected in Cadiz show 13 and 21-23 respectively. Giraldes et al (2018) also refer that the accessory branch of the antennular flagellum cannot be distinguishable before the unguiform free segment in L. uncicornis (see Fig. 1d in Holthuis and Maurin 1952), while it is distinguishable in L. arvoredensis (Giraldes et al 2018).…”

“…The differences to L. grabhami, namely on live specimens, are too conspicuous, as this species is yellow with a continuous middorsal white stripe from the tip of the rostrum to the end of the telson and, at both sides of this one, present a dorsal longitudinal red band (see Kassuga et al 2015). Giraldes et al (2018) mentioned that the stylocerite of L. uncicornis exhibits a series of denticules in its outer margin, while that of L. arvoredensis exhibited none. However, the original description of L. uncicornis mentioned "In some specimens the lateral edges and more especially the outer margin of the stylocerite are denticles near the end of the latter ("Chez quelques specimens les bords latéraux et plus spécialement le bord externe du stylocérite sont lenticules près de l'extrémité de celui-ci."…”

“…The specimens of L. uncicornis and L. seticaudata from Cadiz (Spain) and Portimão (Portugal) examined in the present study were identified according to Holthuis and Maurin (1952), Lagardère (1971), Chace (1997), Baeza and Anker (2008), Froglia and Deval (2014), Anker and Cox (2011), Giraldes et al (2018) and Abdelsalam (2018), and photographed (Figure 3). Two specimens were deposited in the Decapoda and Stomatopoda Crustacean Collection (Spanish Institute of Oceanography in Cadiz, Spain) under catalogue numbers IEO-CD-CAD18/2463-2464 (see Table 1).…”

“…An evolutionary distances analysis was carried out in MEGA6 (Tamura et al 2013), for concatenate 16S and Cox1 sequences obtained in the present study from specimens of L. uncicornis and L. seticaudata, as well as the sequences of other selected group of Lysmata species downloaded from GenBank (http://www.ncbi.nlm.nih.gov), that according to the phylogeny by Giraldes et al (2018) cluster with L. arvoredensis and as outgroup. The phylogenetic reconstruction analyses were inferred from neighbour-joining using the p-distance method.…”

“…It is worth highlighting that the presence of L. wurdemanni in WA is valid, but further studies are still needed (Rhyne et al 2009). More recently new Atlantic species have been described, namely L. rafa Rhyne and Anker, 2007 from Florida (WA) (Rhyne and Anker 2007), L. hochi Baeza and Anker 2008 from the Caribbean Sea (WA) (Baeza and Anker 2008), L. jundalini Rhyne, Calado and Dos Santos, 2012 from Puerto Rico (WA) (Rhyne et al 2012), L. udoi Baeza et al 2009 from Venezuela (WA) (Baeza et al 2009), L. baueri Prakash and Baeza 2017 from Mexico (WA) (Prakash and Baeza 2017), Lysmata napoleoni De Grave and Anker, 2018, from St. Helena (CA) (De Grave and Anker 2018) and Lysmata arvoredensis Girardes, Macedo, Brandão, Baeza and Freire, 2018 from Brazil (WA) (Giraldes et al 2018).…”