40 
PACIFIC SCIENCE, Vol. VII, January, 1953 
DISCUSSION: This species appears to be most 
closely related to S. charon (Heller) of all the 
Hawaiian species. However, to judge from 
Bate’s description and figures, the two spe- 
cies can be separated by a series of character- 
istics. Probably the most important are in the 
carpus of the second leg, which has the first 
article 1.7 times as long as the following four 
together in S. prolificus (according to the fig- 
ure) and only equal to the sum of the follow- 
ing articles in S. charon, and in the biunguicu- 
late dactylus of the third legs, where the base 
of the superior claw is one sixth and the base 
of the inferior claw five sixths the diameter of 
the dactylus in Bate’s figures instead of one 
fourth and three fourths as in 5. charon. Final- 
ly, in the antennules the visible portion of the 
first antennular article is longer than the 
second and third, which are subequal, and the 
tip of the stylocerite reaches only slightly be- 
yond the end of the first article in S. prolificus, 
whereas in S. charon the first and second an- 
tennular articles are subequal, the third is 
shorter, and the tip of the stylocerite reaches 
to the middle of the second antennular article. 
Bate makes no mention of, nor shows any 
detail of, the dactylus of the third leg. If it 
does show the concavity of the inferior ungis 
and the basal expansion of the superior unguis 
characteristic of S. charon (and such a small 
character could easily have been overlooked), 
the two species are certainly most closely re- 
lated. However, the nature of the second legs 
and of the stylocerite would be valid charac- 
teristics for the separation of the two species 
even if the dactyli were similar. 
De Man (1911) suggests that 5. prolificus 
may be a synonym of S. hiunguiculatus (Stimp- 
son) ; the redescription of S. hiunguiculatus in 
this paper removes that possibility. 
There are no specimens of S. prolificus in the 
present collection; it has not been reported in 
the literature since its original description ex- 
cept for two specimens recorded by Ortmann 
which were later re-examined and placed in 
S. gravieri Coutiere (de Man, 1911). This lack 
of distributional records indicates that the 
Fig. 12. Synalpheus prolificus (Bate), a. Lateral aspect 
(slightly over 3X); b, anterior region, dorsal aspect; c, 
third leg, propodus and dactylus. (Redrawn from Bate, 
Challenger Rpts., Vol. 24; Plates, 1888, pi. 99, fig. 4.) 
species is probably restricted to the deeper 
zones and does not reach the reefs; it may also 
indicate that the species is endemic to the Ha- 
waiian Islands, but insufficient sampling of 
deeper water in other areas would make such 
a conclusion questionable. 
Synalpheus pafaneomeris Coutiere 
Figs. 13 a-l, 14 a-h 
Synalpheus paraneomeris Coutiere, Fauna and 
Geog. Maid, and Laccad. 2: 872, 1905. 
Synalpheus townsendi Coutiere {partim), U. S. 
Natl. Mus., Proc. 36: 35, 1909. 
DESCRIPTION: Rostrum narrow and acute, 
not quite reaching to end of first antennular 
article. Orbital hoods produced into teeth 
that reach almost to end of rostrum. Depres- 
sion between rostrum and orbital hoods not 
extensive, but lateral margins of rostral base 
so abrupt that rostrum appears separated from 
anterior carapace in dorsal view. 
