Laomenes nudirostris ( Bruce, 1968 )

Marin, Ivan, 2009, Crinoid-associated shrimps of the genus Laomenes A. H. Clark, 1919 (Caridea: Palaemonidae: Pontoniinae): new species and probable diversity, Zootaxa 1971, pp. 1-49 : 39-46

publication ID	https://doi.org/ 10.5281/zenodo.185020
DOI	https://doi.org/10.5281/zenodo.6213148
persistent identifier	https://treatment.plazi.org/id/03DC87A3-955F-F60E-F1D4-2AD9FA9F278C
treatment provided by	Plazi
scientific name	Laomenes nudirostris ( Bruce, 1968 )
status

Treatment

Laomenes nudirostris ( Bruce, 1968) View in CoL

( Figs. 30–32 View FIGURE 30 View FIGURE 31 View FIGURE 32 , 33 View FIGURE 33 B, D, F)

Parapontonia nudirostris Bruce 1968: 1149 View in CoL , figs. 1–5 [type locality: New Caledonia]; 1992: 78, figs. 25–27. Laomenes nudirostris View in CoL .— 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 View FIGURE 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 View FIGURE 31 B). Orbit well developed; inferior orbital margin produced, rounded. Abdominal somites smooth; pleura of abdominal somites I–V rounded ( Fig. 30 View FIGURE 30 ). Telson about 3 times as long as wide in proximal part ( Fig. 31 View FIGURE 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 View FIGURE 31 C, D), eyestalk stout, as long as wide, with ovate cornea bearing distinct short papilla in central part. Antennule well developed ( Fig. 31 View FIGURE 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 View FIGURE 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 View FIGURE 32 A). Pereiopod II equal in size and shape, with robust segments ( Fig. 32 View FIGURE 32 B); carpus flared distally ( Fig. 32 View FIGURE 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 View FIGURE 32 E). Pereiopod III slender, with segments unarmed; carpus produced at carpo-propodal articulation ( Fig. 32 View FIGURE 32 F, G); propodus without distoventral spines ( Fig. 32 View FIGURE 32 H), with row of long slender plumose setae distally; dactylus ( Fig. 32 View FIGURE 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 View FIGURE 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 View FIGURE 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.