Paranamixis dentidactylus, Myers, A. A., 2013

Myers, A. A., 2013, Amphipoda (Crustacea) from Palau, Micronesia: Families Dexaminidae, Eusiridae, Hyalidae, Ischyroceridae, Leucothoidae and Lysianassidae, Zootaxa 3731 (3), pp. 301-323 : 320-321

Paranamixis dentidactylus sp. nov.

( Figs 16 , 17 )

Type material. Holotype male, 2.1 mm (OUMNH.ZC.2002.24.109) Outside Malakal Harbour, light trap sample, 190 feet deep; 07°16.366' N, 134°27.906'E; leg. S. De Grave & C. Burras, night 1st–2nd June 2002. Etymology. Named for the well developed spine on the dactylus of the gnathopod 2. Description. Based on male holotype, 2.1 mm.

Head head hood-like with a small triangular rostrum, lower margin with small spine. Antenna 1 about one third body length; peduncular article 1 stout equal in length to peduncular articles 2+3. Antenna 2 slender, shorter than antenna 1. Maxilliped fused basally; inner plates entire; dactylus elongate, equal in length with fourth palp article.

Pereon. Gnathopod 1 absent, coxa 1 minute. Gnathopod 2 coxa longer than broad with sharply rounded anterodistal corner; basis elongate and slender broadening distally, without teeth, spines or serrations; propodus irregularly subovoid, palm with four rounded spines; dactylus elongate, posterior margin with well developed rounded spine at about two-thirds its length. Pereopods 3 – 4 slender; dactylus less than half length of propodus. Pereopod 5 basis posterior margin angular, broadest medially. Pereopod 7 basis subquadrate.

Pleon. Epimera 1 – 3 rounded. Uropod 1 longer than uropod 2. Uropod 3 missing in specimen, Telson entire, spoon-shaped.

Remarks. Paranamixis dentidactylus is closest to P. indicus Sivaprakasam, 1968 . The leucomorph stage is unknown. It differs from it; however, in a number of ways. The male coxa 2 in P. dentidactylus is longer than broad with smooth margins, whereas that of P. indicus is almost round with two ‘teeth’ on the anteroproximal margin. The basis of P. indicus bears a small spine, absent in P. dentidactylus . The propodus palm of P. dentidactylus has a series of four rounded spines whereas that of P. indicus has two spines. The basis of pereopod 7 in P. dentidactylus is quadrate whereas in P. indicus it is rounded.

Distribution. Known only from the type locality.

Figures

FIGURE 16. Paranamixis dentidactylus sp. nov., holotype male, Palau.

FIGURE 17. Paranamixis dentidactylus sp. nov., holotype male, Palau.