429 



765. Alphetis rnalabaricus (Fabr.) Henderson var. leptopjts de Man. 



Alpheus dolichodactylus Ortm. var. leptopus J. G, de Man, in: Tijdschr. d. Ned. Dierk. Vereen., 



(2) Dl. XI, 1910, p. 289. 

 Confer: Alpheus malabaricus (J. C. Fabricius), J. R. Henderson, in: Trans. Linn. Soc. London 



Zool. Sen 2, Vol. 5, 1893, p. 434, PL XL, figs, i — 3. 

 Alpheus dolichodactylus A. Ortmann, in: Zoolog. Jahrb. V. Abtli. f. Syst. 1890, p. 473, Taf. 



XXXVI, fig. II.' 

 Alpheus dolichodactylus F. Doflein, in: Abhandl. k. bayer. Akad. Wiss. II CI. XXI. Bd. III. 



Abth. 1902, p. 634. 



Stat. 12. March 14. 7°i5'S., II5°I5'.6E. Bali Sea. 289 m. Mud and broken shells, i egg- 

 bearing female. 



Stat. 19. March 19/21. 8°44'.5 S., ii6°2'.5E. Bay of Labuan Tring, West coast of Lombok. 

 18 — 27 m. River-mud, coral, coralsand. 2 males and i ova-bearing female. 



Stat. 213. September 26 — October 26. Saleyer-anchorage and Surroundings. 18 — 45 m. Mud 

 and mud with sand, i mutilated specimen. 



Stat. 311. February 12/13. Sapeh-bay, East coast of Sumbawa. Depth up to 36 m. Mud and 

 sand. 4 males. 



Alpheiis dolichodactyhis Ortm., of which three adult specimens, cotypes, from Sagami 

 bay, Japan, that I received from the Museum at Strassburg, are lying before me, is no doubt 

 identical with a species which in 1893 has been described by Henderson as the true A. malabaricus 

 Fabr. This identity was already surmised in 1899 by Professor Coutiere ("Les Alpheidae", p. 46 

 and 48). The basal tooth on the dactylus of the small chela occurs in the Japanese specimens 

 exactly as in Henderson's figure and the large chela also perfectly agrees with that figured by 

 this author. In the largest of these specimens that is 34 mm. long, the larger chela is 18 mm. 

 long, the fingers 7 mm., just as indicated by Henderson but there is no trace of a tooth on 

 the upper margin of the dactylus, which was supposed by this author to occur near the base 

 of this finger, though it was not described by Dr. Ortmann. In the specimens from Japan the 

 fingers are slightly gaping and this proves to be the only difference, for their form is 

 the same as figured in the "Transactions"; this slight difference, however, may at most be 

 regarded as a local feature, if it is indeed always present and, in this case, the species from 

 Japan should be considered as a variety dolichodactylus Ortm. 



The specimens, collected by the "Siboga", now differ from those from Japan by their 

 smaller size and by the thoracic legs being of a more slender shape. 



The adult egg-bearing female from Stat. 19 is 26 mm. long, the other specimens are 

 of the same size or but a little shorter. 



Rostrum acute, almost as broad at its base as it is long, usually reaching to the middle 

 of the visible part of first antennular article and projecting with half its length beyond the 

 rounded and unarmed, orbital hoods, that are as prominent as in A. paralpheopsides \ in other 

 specimens, as e.g. in the ova-bearing female from Stat. 19, the rostrum reaches only to the 2"'^ third 

 of the visible part of basal article, hardly projecting beyond the orbital hoods. In a specimen 

 long 20 mm. from Stat. 3 1 i the rostrum is wanting entirely, though the interorbital carina is 

 well-developed: this is, apparently, an abnormal individual. Interorbital carina low, concealed 

 in a lateral aspect by the orbital hoods, gradually widening a little backward and e.xtending 

 to the base of the orbital hoods from which it is separated by narrow, moderately deep grooves. 



297 



SIBOGA-EXPEDITIE XXXIX fl'. 55 



