Laomenes nudirostris Bruce 1968
Creators: name: Marin, Ivan
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Palaemonidae
Laomenes
Laomenes nudirostris

description: Laomenes nudirostris (Bruce, 1968)
(Figs. 30–32, 33 B, D, F)
Parapontonia nudirostris Bruce 1968: 1149, figs. 1–5 [type locality: New Caledonia]; 1992: 78, figs. 25–27. Laomenes nudirostris.— Okuno & Fujita 2007: 121, fig. 3.
Material. Vietnam, Nhatrang Bay: 1 ovigerous female (pcl. 5.1 mm), 1 male (pcl. 3.0 mm) (ZMMU), Tre Island, Mui Nam, 7 m, on crinoid Amphimetra tesselata, 18.vii.2006, coll. I. Marin; 1 male (pcl. 2.7 mm); 1 male (pcl. 2.4 mm) (ZMMU), Tre Island, Mui Nam, 8 m, on crinoid Amphimetra tesselata, 18.vii.2006, coll. I. Marin; 1 ovigerous female (pcl. 4.3 mm), 1 male (pcl. 3.0 mm) (ZMMU), Mun Island, 8 m, on crinoid Amphimetra tesselata, 18.vii.2006, coll. I. Marin; 1 ovigerous female (pcl. 3.5 mm), 1 male (pcl. 2.2 mm), 1 juv. (pcl. 2.0 mm) (ZMMU), Mun Island, 5–10 m, on crinoid Himerometra robustipinna, 26.v.2006, coll. I. Marin; 1 ovigerous female (pcl. 3.0 mm), 1 male (pcl. 2.5 mm) (ZMMU), Mun Island, 5 m, 18.vi.2006, coll. I. Marin; 1 ovigerous female (pcl. 4.7 mm), 1 male (pcl. 2.6 mm) (ZMMU), Mun Island, 10 m, on crinoid Amphimetra tesselata, 27.vi.2006, coll. I. Marin; 1 male (pcl. 2.0 mm) (ZMMU), Mun Island, 10–12 m, on crinoid Amphimetra tesselata, 27.vi.2006, coll. I. Marin; 1 female (pcl. 2.2 mm), 2 males (pcl. 2.6, 2.5 mm) (ZMMU), Dun Island, 15 m, on crinoid Himerometra robustipinna, 04.vi.2006, coll. I. Marin.
Diagnosis. Carapace swollen, smooth, with antennal and hepatic teeth (Fig. 31 A); hepatic tooth triangular, larger than antennal. Rostrum long, slender, straight, compressed and tapering distally, with well developed dorsal and ventral carina, without dorsal and ventral teeth. Lateral rostral lamina forming conspicuous supraorbital teeth in proximal part (Fig. 31 B). Orbit well developed; inferior orbital margin produced, rounded. Abdominal somites smooth; pleura of abdominal somites I–V rounded (Fig. 30). Telson about 3 times as long as wide in proximal part (Fig. 31 I), narrowing posterior, with 2 pairs of small submarginal dorsal spines at 0.5 and 0.75 of telson length. Eyes large and well developed (Fig. 31 C, D), eyestalk stout, as long as wide, with ovate cornea bearing distinct short papilla in central part. Antennule well developed (Fig. 31 E); distolateral margin of basal antennular segment with acute distolateral tooth and well developed medial projection, submarginal ventral tooth small but distinct, situated near medial border of basal segment. Mandible robust, without palp; incisor process broad, with 7 or 8 terminal teeth (Fig. 31 F); molar process well developed, robust, with several teeth distally. Maxillule normal, with well developed bilobed palp; upper lacinia slightly curved, flaring distally, with strong setae distally; lower lacinia robust, flaring distally. Maxilliped I with endites fused. Maxilliped II with slender segments and broad exopod. Pereiopod I slender, carpus without distolateral setae at carpo-propodal articulation; dactylus and fixed finger robust with numerous terminal setae, cutting edge entire, tip not spatulated (Fig. 32 A). Pereiopod II equal in size and shape, with robust segments (Fig. 32 B); carpus flared distally (Fig. 32 C, D), as long as maximal width, with distinct ventrolateral notch; palm cylindrical; fingers slender, with cutting edge entire bearing 7 distinct triangular teeth, with simple, curved tips (Fig. 32 E). Pereiopod III slender, with segments unarmed; carpus produced at carpo-propodal articulation (Fig. 32 F, G); propodus without distoventral spines (Fig. 32 H), with row of long slender plumose setae distally; dactylus (Fig. 32 H) robust, as long as maximal width, with well developed, long, acute and curved unguis and small accessory tooth turned down, accompanied with tuft of long slender setae. Pereiopods III–V similar. Exopod of uropod with single mobile spine distolaterally.
Color. Coloration of the species is similar to Laomenes ceratophthalmus. General coloration of the body and appendages is red with several dark red longitudinal bands on carapace and abdomen dorsolaterally and laterally (Fig. 33 B, D, F).
Remarks. Morphology and coloration of L. ceratophthalmus and L. nudirostris is very similar, but the species clearly differs by rostral formula. The rostrum of L. ceratophthalmus possesses 3 dorsal teeth while rostrum of L. nudirostris is toothless. The apical papilla of the eyes is larger in L. ceratophthalmus.
Host. All specimens were collected from the himerometrid crinoids Himerometra robustipinna (Carpenter, 1881) and Amphimetra tesselata (Müller, 1841) (Crinoidea: Himerometridae) (Fig. 34 A, B). Other crinoids known as hosts of this species in other localities are Pontiometra andersoni (Carpenter, 1889) (Himerometridae) and Tropiometra afra Hartlaub, 1890 (Tropiometridae) (Bruce 1968, 1971, 1981, 1982, 1992).
Distribution. Known from Indonesia, the Great Barrier Reef of Australia, New Caledonia and Japan.
description: Published as part of Marin, Ivan, 2009, Crinoid-associated shrimps of the genus Laomenes A. H. Clark, 1919 (Caridea: Palaemonidae: Pontoniinae): new species and probable diversity, pp. 1-49 in Zootaxa 1971 on pages 39-46, DOI: 10.5281/zenodo.185020