Lysmata udoi Baeza, Bolaños, Hernandez & López, 2009, n. sp.
Creators: name: Baeza, Antonio
name: Bolaños, Juan A.
name: Hernandez, Jesús E.
name: López, Régulo
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Hippolytidae
Lysmata
Lysmata udoi

description: Lysmata udoi n. sp.
(Figures 1–3)
Type material. Holotype: simultaneous hermaphrodite (carapace length [CL] 8.0 mm, CL+ rostrum [R] 14.55 mm mm), MOBR-C-1547, Caribbean coast, Cubagua Island, Venezuela, from dens of the “sapo bocón” toadfish, Amphichthys criptocentrus (Valenciennes, 1837), 2–4 m, colls. R. Lopez and J. A. Baeza, 15–20 Aug 2008. Paratypes: 1 ovigerous simultaneous hermaphrodite (CL 7.77 mm, CL + R 13.66 mm), MOBR-C-1548, same collection data as for holotype; 1 male (CL 7.35 mm, CL+R 13.95 mm), MOBR-C-1549, same collection data as for holotype.
Description. Rostrum elongate, slender, slightly curved upwards, about 0.9 times as long as carapace, slightly surpassing end of antennular peduncle (Fig. 1 a–b); dorsal margin with six teeth, posterior tooth situated just anterior to middle of carapace, second tooth just posterior of postorbital margin, single seta present between all teeth; ventral margin with five teeth, most-proximal ventral tooth situated at the same level of fifth most-proximal dorsal tooth at mid-length level of first antennular segment; tip of rostrum bidentate (Figs. 1 b). Carapace smooth, 1.2–1.3 times as long as high, posteroventral margin rounded; pterygostomial angle rounded, without tooth (Fig. 1 c). Eyes moderately large, not reaching dorsal margin of rostrum (Fig. 1 a–d). Antennal tooth long, reaching to posterior margin of cornea (Fig. 1 a–c). Antennular peduncle not reaching scaphocerite, about 0.75 times as long as scaphocerite, first segment about 2.0–2.2 as long as second segment, second segment about 1.6 times as long as third segment; disto-dorsal margin of all three peduncular segments furnished with series of spinules; stylocerite overreaching anterior margin of eye, reaching or just over-reaching mid-length of first antennular segment (Fig. 1 a–c); ventro-mesial carina with small, anteriorly directed tooth (Fig. 1 d); lateral antennular flagellum long, with aesthetascs extending from fourth to 31st segment (Fig. 1 e); accessory branch of outer ramus rudimentary (Fig. 1 e). Scaphocerite 4.4–4.8 times as long as wide, lateral margin slightly concave, distolateral tooth considerably over-reaching distal margin of blade (Fig. 1 f).
Abdomen more than twice carapace length. Pleura of first four abdominal somites with rounded margin (pleuron of fourth somite without postero-lateral tooth); pleuron of fifth somite with sharp posterolateral tooth; sixth somite about 1.3 times longer than fifth somite, with acute posteroventral tooth and acute posterior tooth flanking base of telson (Fig. 1 g). Telson about 1.7–1.9 times as long as sixth abdominal somite, tapering posteriorly; dorsal surface with two pairs of spines (Fig. 1 h); posterior margin medially acute, with pair of long slender spines each flanked by shorter spine (Fig. 1 h–i); two long plumose setae present between long spines (Fig. 1 h–i).
Mouthparts typical for genus, third maxilliped over-reaching scaphocerite; exopod about 0.6 times as long as antepenultimate segment of endopod; ultimate segment 1.6–1.7 times as long as penultimate segment; with tip furnished with 9 spines, 3 distal, 3 subdistal and other 3 more proximal (Fig. 1 j–k). First pereiopod with simple chela (Fig. 2 a–b), reaching beyond end of scaphocerite when fully extended, ischium with row of spines along ventral margin (Fig 2 b–c); carpus about 0.8–0.9 times the length of the merus, chela subequal to carpus, palm about three times as long as dactylus, six times as long as high (Fig. 2 a–b). Second pereiopods slender, subequal in length, ending in small simple chelae; merus with 20 articles, carpus about 1.7 times the length of the merus, reaching beyond third article of antennular peduncle, with 33 articles (Fig. 2 d). Ischium with row of proximal spines along ventral margin (Fig. 2 e).
Third to fifth pereiopods similar, decreasing in length from third to fifth. Third pereiopod reaching beyond third article of antennular peduncule, merus with seven spines, about 2.5–2.7 times as long as ischium; carpus about half as long as merus, unarmed; propodus about 1.5 times as long as carpus; dactylus about 1/6 times as long as propodus (Fig. 2 f), biunguiculate, dorsal unguis slightly longer than ventral one, flexor margin of dactyl armed with 3 pinules, decreasing in size from proximal to distal. Fourth pereiopod similar to third, carpus reaching beyond third article of antennular peduncle. Fifth pereiopod similar, with merus about 1.4 times carpus length, reaching beyond third article of antennular peduncle, bearing three spines; propodus with rows of dense setae on distal end of flexor margin (Fig. 2 g). Uropod typical for the genus, without special features (Fig. 1 l).
Color in life. Body translucent with red longitudinal and diagonal stripes (Fig. 3), carapace with inverted V-shaped band, abdominal pleura with narrow longitudinal stripes (dorsal showing from 5 to 3, none of them running entirely along the length of the abdomen); third pleuron with wide transverse band; fourth pleuron almost lacking pigments, with the exception of a transverse band (not as conspicuous as on third pleuron) with three longitudinal short lines (two lateral and one medial) projecting interiorly, but not reaching middle section of the pleuron; telson and uropods with intense red longitudinal bands. Color of early embryos and eggs pink. Late stage embryos turning silver brown.
Size. The male specimen is 7.35 mm CL; the hermaphrodites are 7.77–8.04 mm CL.
Ecology. In crevices or cracks used by the toadfish Amphichthys criptocentrus (Valenciennes, 1837), in sand, coral rubble, or live coral bottoms. Additional diving observations indicated that this species inhabits their refuges in small groups. Only the larger shrimp within a group were found brooding embryos suggesting that the species is a protandric simultaneous hermaphrodite as reported for other species of Lysmata whose sexual system has been studied (Baeza 2009).
Type locality. Cubagua Island, South Caribbean, Venezuela.
Distribution. Presently only known with certainty from Isla Cubagua and Isla Margarita, Venezuela.
Etymology. The new species is named after the Universidad de Oriente, Venezuela.
Variation. The material presents no or moderate variation compared to other closely related species (see below). With respect to rostral teeth, the current material exhibits no variation with all of specimens having 6 dorsal and 5 ventral teeth. Segmentation of the merus in the second pereiopod usually ranged between 20 and 23 articles, with often a minor difference between the left and right pereiopod. One specimen (MOBR-C- 1548) presented greater variation with 26 and 19 articles in the left and right perereipod, respectively. Similarly, segmentation of the carpus in the second pereiopod varied between 33 and 37, and differed by 3 or less articles between the left and right pereiopod. Lastly, variation in the number of movable spines on the meri of the ambulatory pereiopods was slightly more variable: 5–9, 4–8 and 3–4 on the third, fourth and fifth pereiopod respectively. A difference of 1 or 2 spines between the left and right pereiopods was observed.
Remarks. The new species is morphologically closest to L. ankeri Rhyne and Lin, 2006, L. rafa Rhyne and Anker, 2007 and L. boggessi Rhyne and Lin, 2006, all species recently described from the Gulf of Mexico or northern Caribbean Sea (Rhyne & Lin 2006; Rhyne & Anker 2007) that pertain to the Neotropical clade of peppermint shrimps (Baeza et al. 2009). Lysmata udoi resembles L. rafa in having a relatively long and slender rostrum and walking legs, but not as long and slender as in the latter species. Also, L. udoi resembles L. ankeri in having a moderately curved rostrum with six dorsal and five ventral teeth. Nevertheless, L. udoi n. sp. can be distinguished from the three species above by a combination of characters that include the number of tooth, length and shape of the rostrum (dentition: six dorsal and five ventral in L. udoi compared to seven or more dorsal and seven to nine ventral in L. rafa and usually four to five dorsal and three to five ventral in L. boggessi; rostrum length: 0.9 times as long as carapace in L. udoi compared to 1.2 in L. rafa, usually less than 0.8 in L. boggessi and 0.6–0.8 in L. ankeri; shape: moderately curved in L. udoi compared to well curved in L. rafa and mostly straight in L. boggessi), the relative length of the antennular peduncule (about 0.75 times as long as scaphocerite in L. udoi compared to reaching or overreaching the scaphocerite in L. rafa and approximately 0.5 times as long as scaphocerite in L. ankeri), the shape of the scaphocerite (4.4–4.8 times as long as wide in L. udoi compared to five to six times in L. rafa, approximately 4.5 in L. boggessi and approximately 3.9 in L. ankeri) and the number of carpal articles in the second pereipod (33–37 in L. udoi compared to 40–43 in L. rafa, most often 26–28 in L. boggessi and 33–41 [but usually 35–37] in L. ankeri).
Lysmata udoi n. sp. can be distinguished from L. ankeri, L. rafa and L. boggessi by the color pattern. In dorsal view, L. udoi n. sp. shows five lines in the second and third abdominal somites, all interrupted, and no line runs entirely along the abdomen. In contrast, L. rafa shows three lines and the medial one runs along the entire length of abdomen. In turn, L. boggessi features continuous very narrow longitudinal stripes situated between broader and more intense longitudinal stripes. Also, in L. boggessi, the telson and uropods are dark blue and the third abdominal somite lacks the red transverse band present in the new species. Lastly, L. ankeri features continuous and narrow longitudinal stripes running entirely along the abdomen. As in L. udoi, L. ankeri shows a broad, transverse, broadly U-shaped band in the third pleuron. However, this band is not as marked as in L. udoi. Nevertheless, the most distinctive color feature in L. udoi n. sp is located in the fourth abdominal somite that almost lacks color but bears a posterior thin line with three short forward projections.
Phylogenetic analyses. A 550-nucleotide sequence of the section of 16S gene was obtained the two selected specimens (Genbank accession numbers GQ227815 and GQ227816). The two sequences were a close match with 0.36% sequence divergence. The phylogenetic analyses confirmed that the new species pertains to the Neotropical clade and is more closely related to L. boggessi Rhyne and Lin, 2006 and L. rafa Rhyne and Anker, 2007 (Fig. 4) than to L. ankeri Rhyne and Lin, 2006. Nevertheless, its status either as geminate of L. boggessi or L. rafa was not supported by any one of the phylogenetic analyses (Fig. 4).
description: Published as part of Baeza, Antonio, Bolaños, Juan A., Hernandez, Jesús E. & López, Régulo, 2009, A new species of Lysmata (Crustacea, Decapoda, Hippolytidae) from Venezuela, southeastern Caribbean Sea, pp. 60-68 in Zootaxa 2240 on pages 62-67, DOI: 10.5281/zenodo.190531