Metadynomene tanensis ( Yokoya, 1933 )

Mclay, Colin L. & Ng, Peter K. L., 2005, On a collection of Dromiidae and Dynomenidae from the Philippines, with description of a new species of Hirsutodynomene McLay, 1999 (Crustacea: Decapoda: Brachyura), Zootaxa 1029 (1), pp. 1-30 : 24-25

Metadynomene tanensis ( Yokoya, 1933)

Dynomene tanensis Yokoya, 1933: 96 , fig 38.

Dynomene praedator .— Sakai 1976: 30, fig. 17 (not Dynomene praedator A. Milne­Edwards, 1879 ).

Metadynomene tanensis .— McLay 1999: 521, figs. 4d, 6c, 7f, 9d, e, 11, 13c, e, f, 14e, 25b, 27, 28.—McLay et al. 2001: 964.— Ng et al. 2001: 6.

Material. 1 male, 17.0 x 15.8 mm, 200–300 m, 28 Nov 2001, ZRC 2001.524 ; 2 males, 15.1 x 14.0 mm, 17.4 x 16.3 mm, 200–300 m, Jun 2002, ZRC 2002.629 ; 1 female, 17.3 x 15.7 mm, 200–300 m, 25–30 Jul 2003, ZRC 2003.677 ; 2 males, 21.2 x 19.8 mm, 22.6 x 21.2 mm, 200–300 m, 2 Mar 2004, ZRC / NMCR. All locations in Balicasag Island, Panglao, Bohol, Visayas, Philippines; purchased from local shell fishermen, obtained by tangle nets .

Remarks. All species of Metadynomene are covered with short soft setae and easily separated from other dynomenids. The present female (17.3 x 15.7 mm) carried a small Sacculina parasite under the abdomen.

Distribution. Metadynomene tanensis is a deep water dynomenid that has been found in the range 205– 520 m. Its distribution includes Japan, Taiwan, Indonesia, Vanuatu, New Caledonia, Loyalty and Chesterfield Islands. Therefore the occurrence of M. tanensis in the Philippines is a new record, but it does not extend the geographic range of the species.

McLay (1999: 522) reported a large male specimen (29.1 x 27.6 mm) from Tuamotu, French Polynesia as being M. tanensis , but it now appears this specimen belongs to a new species. The anterolateral teeth are much smaller than in the present specimens and are arranged differently. We prefer to wait until more specimens, including females, become available before describing it as a new species. Thus the distribution of M. tanensis is now confined to the west Pacific. The Tuamotu specimen should be referred to as Metadynomene aff. tanensis for the time being. Exclusion of this large male makes the maximum size of M. tanensis 23.7 x 21.4 mm for males and 24.8 x 22.4 mm for females.