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Synalpheus Iocasta differs from Syn. Pococki Cout. at first sight by the different form 

 and characters of the propodi of the three posterior legs. 



f 15a. Synalpheus par aneomeris Cout. var. pracdabundus de Man. 



J. G. DE Man, in: Tijdschr. d. Ned. Dierk. Vereen. (2) Dl. XI, 1909, p. 123. 



Confer: H. COUTIÈRE, Alpheidae Mald. and Laccad. Archip. 1905, p. 872, PI. LXXI, fig. 7. 



Stat. 34. March 27. Anchorage off Labuan Pandan, Lombok. Coralreef. 2 young specimens. 

 Stat. 37. March 30/31. Sailus ketjil, Paternoster-islands. Coralreef. 1 ova-bearing female. 

 Stat. 129. July 22/23. Anchorage off Kawio- and Kamboling-islands, Karkaralong-group. Reef. 



4 specimens, 2 of which with eggs. 

 Stat. 250. December 6/7. Anchorage off Kilsuin, West-coast of Kur-island. Reef. 3 specimens, 



1 of which with eggs. 



These specimens show a few slight differences from the typical form of Syn. par aneomeris 

 Cout. and are therefore described as a new variety : the specimens taken at Stat. 129 are 

 regarded as the types of this variety. Rostrum and lateral frontal spines as in the typical species 

 (H. Coutière, 1. c. fig. 7'), but they are more acuminate and the tips of the lateral spines are 

 distinctly turned inward. Carpocerite 3,54-times, in the typical species 4-times as long as wide; 

 scaphocerite, lower spine of the basicerite, antennular peduncle and stylocerite exactly as in the 

 typical form. 



Telson a little shorter and a little less wide anteriorly with regard to the width of the 

 posterior margin than in the variety halmahcrcnsis\ anterior pair of spinules, long 0,16 mm., 

 usually situated a little before the middle, rarely just in the middle, but never, as in the 

 variety halmaher ensis, posterior to the middle. The spinules of the upper surface are a little 

 farther remote from the lateral margins than in the typical species and than in the variety 

 halmaher ensis, they are situated as in the variety prolattis\ posterior margin as in the typical 

 species, the outer angles, however, acute. 



The two chelipeds apparently accord with those of the typical species (Coutière, 1. c, 

 &g- 7 a i 7^)i but the upper margin of the merus ends in a small acute tooth. 



Merus of second legs 5,8 — 6-times as long as wide; first carpal segment 5 — 5,3-times 

 as long as thick, slightly shorter than the sum of the following, second segment a little 

 longer than the third, third as long or a little longer than the fourth ; the chela, the fingers 

 of which are hardly longer than the palm, appears a little more than one and a half as long 

 as the fifth segment. Relative dimensions of the third legs: carpus i; merus 2; propodus 1,64 

 or: carpus i; merus 1,94; propodus 1,63. Merus 3,56 — 3,58-times as long as wide, of a 

 stouter shape than in the typical species, in which it is 4-times as long as wide ; propodus 

 5,53 — 5,75-times as long as wide, armed with 6 or 7 spinules, that are 0,15 — 0,16 mm. 

 long. The length of the dactylus, measured from the proximal encl of the anterior margin to 

 the tip of the ventral hook, is a little more than one-fourth the propodus ; the dorsal hook 

 appears decidedly longer than the other, which, at its base, is one-third thicker than the dorsal 

 hook. Relative dimensions of the fourth legs: carpus i; merus 1,8; propodus 1,7 or carpus i; 

 merus 1,85; propodus 1,71. Merus 3,38 — 3,42-times, propodus 5,66 — 5,46-times as long as 



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