Kemponia grandis ( Stimpson, 1860 )

Li, Xinzheng, 2008, Report on some species of Palaemonidae (Crustacea, Decapoda) from French Polynesia, Zoosystema 30 (1), pp. 203-252 : 215-217

Kemponia grandis ( Stimpson, 1860)

Anchistia grandis Stimpson, 1860: 39 .

Periclimenes grandis – Borradaile 1898: 382. — Chace & Bruce 1993: 112. — Poupin 1998: 16. — Li 2000: 186, fig. 235; 2004: 69. — Li & Liu 2004: 93, fig. 4.

Kemponia grandis – Bruce 2004b: 16 . — Li et al. 2004: 530. — Li & Bruce 2006: 644 .

MATERIAL EXAMINED. — Marquesas Is. Ua Huka, south coast of Hiniaehi Bay, MUSORSTOM 9, malacologists, stn 32, 8°56.10’S, 139°32.70’W, 12-17 m, sand, detritus with algae, coll. Cosel, Tröndlé & Tardy, X.1997, 1 ♂ (MNHN-Na 15472).

Austral Is. Rapa I., Hiri Bay, BENTHAUS, malacologist fieldwork, stn 9, 27°37.3’S, 144°22.2’W, 3-24 m, corals, 6.XI.2002, 1 ovig. ♀ (MNHN-Na 15470). — Vavai, BENTHAUS, malacologist fieldwork, stn 32, 27°35.8’- 27°35.0’S, 144°23.0’- 144°22.7’W, 15-20 m, corals, 18-23.XI.2002, 1 ♂, 1 ovig. ♀ (MNHN-Na 15466).

DISTRIBUTION. — Type locality: Amami O Shima, Ryukyu Is. Previously also known from Israel, Egypt, Djibouti, Aden, Kenya, Zanzibar, Tanganyika, Mozambique, Comoro Is, Madagascar, Seychelles, Sri Lanka, Burma, Malaya, Singapore, Indonesia, Japan, Australia (Northern Territory, Queensland), Marshall Is, Fiji Is, New Caledonia, Tuvalu, French Polynesia (Tuamotu Is) ; shallow waters, 0-24 m depth. Not previously recorded from Austral and Marquesas Islands, although it is one of the most widely distributed Indo-West Pacific pontoniine species. The 24 m collection depth of the specimen from Rapa, Hiri Bay represents the deepest bathymetric record with certainty of the species so far .

Kemponia rapanui ( Fransen, 1987) n. comb. ( Fig. 6 )

Periclimenes rapanui Fransen, 1987: 519 , figs 13-15. — Li 2000: 230, fig. 305. — Poupin 2003: 21.

MATERIAL EXAMINED. — Austral Is. Neilson Reef, BENTHAUS, stn CP 1922, 27°03.7’S, 146°03.9’W, 150-163 m, 11.XI.2002, 1 ovig. ♀ (cl 2.22 mm) (MNHN- Na 15996). — Neilson Reef, BENTHAUS, stn CP 1918, 27°03.4’S, 146°04’W, 130-140 m, 11.XI.2002, 1 ♂ (MNHN-Na 15981).

DISTRIBUTION. — The species has been previously known only from its type locality:Tahai, Easter Island. The present record extends not only the bathymetric range of the species from 30-39 m to 30-163 m, but also the geographic range from the East Pacific to the French Polynesia.

Usually, the species of Kemponia are shallow water species. The bathymetric range 130-163 m of the present specimens is very deep in the genus. However, two other species of the genus have also been found at more than 100 m depth. The bathymetric ranges of K. nilandensis (Borradaile, 1915) and K. tenuipes ( Borradaile, 1898) are 117-133 m and 105-160 m respectively. The collection depth 163 m of the present ovigerous female is the deepest record of Kemponia up to date.

REMARKS

The specimens are close to the original description of Fransen (1987), except for the following differences: the proximal segment of the left antennular peduncle of the ovigerous female bears two distolateral teeth; the second pereiopod is longer and more slender than in the types, the palm is 4.54 times longer than wide, vs. 4 times in the types, the carpus is subequal to the palm length, vs.shorter than palm in the type material of K. rapanui n. comb. Other minor differences are: the epigastric tooth is situated at 0.26 (vs. 0.3 in type specimens);two pairs of dorsal telson spines are present at 0.30 and 0.60 of telson length (vs. 0.33 and 0.67); the eye has a conspicuous accessory pigment spot (vs. inconspicuous); the antennular peduncle reaches the tip of rostrum (vs. to the 0.8 of the length of rostrum), the proximal segment is 2.03 times longer than maximum width (vs. 3.0); the first pereiopods reach beyond the distal end of the scaphocerite by the chela (vs. not exceeding the scaphocerite), the fingers are 1.32 times the palm length (vs. 1.25); the dactyl of ambulatory pereiopod is 0.17-0.21 as long as the propod (vs. 0.15), the propod is about 22 times longer than the width (vs. 15).

Features which were not mentioned by Fransen (1987) are: sixth abdominal somite 0.56 of carapace length; telson 0.61 of carapace length, dorsal telson spine length 0.09 of telson length; eyes with corneal diameter0.31 of carapace length;proximal antennular peduncle segment is 0.50 of carapace length; palm of the first pereiopod 0.25 of carapace length; propod of ambulatory pereiopod 0.85of carapace length;uropod far exceeding telson, exopod 0.62 of carapace length, exceeding tips of intermediate posterior telson spines, 2.64 times longer than maximum width, endopod 0.94 of exopod length, 3.78 times longer than wide; with about 27 eggs, egg length about 0.63 mm.

Periclimenes rapanui has been found previously only from the type locality, Tahai on the west coast of Easter Island ( Fransen 1987).

Because the species bears a slender finger-like process on the fourth thoracic sternite, which is one of the key features of the genus Kemponia , and as the species fits within the diagnosis of the genus given by Bruce (2004b), P. rapanui is herein transferred to Kemponia .

Figures

FIG. 6. — Kemponia rapanui (Fransen, 1987) n. comb., ovig. ♀ (cl 2.22 mm) (MNHN-Na 15996): A, body, lateral view; B, thoracic sternites; C, eye; D, second, third and distal proximal segments of antennular peduncle; E, second pereiopod. Scale bars: A, B, E, 1 mm; C, D, 0.5 mm.