439 

 fyi. Alpheus sp. 



Stat. 33. March 24/26. Bay of Pidjot, Lombok. Depth 22111. and less. Mud, coral and coral- 

 sand. 1 egg-bearing fcmale. 



Unfortunately this specimen has lost the large cheliped and the legs of the 2 nd , 4" 1 and 

 5 th pairs, so that I do not like to describe it as a new species, which it seems to be : it closely 

 resembles A. parvi-rostris Dana, but it differs at first sight by the more slender shape 

 of the third legs that are unarmed. 



Rostrum acute, twice as long as broad at its base, reaching to the end of first antennular 

 article, frontal margin presenting at either side an obtuse prominence, exactly as in A. parvi-rostris ; 

 the lovver margin of the rostrum projects horizontally forward, while the upper margin is ascending. 

 Rostral carina subacute, compressed, separated by narrow, deep grooves from the rounded orbits, 

 posteriorly obtuse and hardly reaching beyond the base of the latter. Telson 3,6-times as long 

 (1,38 mm.) as its posterior margin is broad (0,38 mm.), greatest width twice as broad (0,8 mm.) 

 as the posterior margin; spinules of the upper surface 0,15 mm. long, at some distance from 

 the lateral margin, anterior pair inserted just in front of the middle, its distance from the base 

 ot the telson being in proportion to the distance from the posterior margin as 3:4: posterior 

 pair just as far distant from the anterior pair as from the posterior margin; inner spinules of 

 the hardly prominent, posterior margin half as long as the latter. 



In a female of the same size of A. parvi-rostris from Stat. 91 the posterior margin of 

 the telson measures one-third of its length, being broader than in the species from Stat. 33, and 

 it is a little broader than half the greatest width ; the anterior pair of spinules is situated more 

 forward, just as far from the anterior margin as the posterior pair from the posterior margin 

 and the latter distance is one and a half as large as the distance between the two pairs of spinules. 



The second antennular article is twice as long as thick, one-third longer than the visible 

 part of the first and one and a half as long as the third article ; the stylocerite ends in 

 a slender spine that is turned inward and it reaches to the 2 nd sixth part of the second 

 antennular article. 



Basicerite armed, just as in A. parvi-rostris, with a long, slender spine, that 

 reaches as far forward as the stylocerite ; carpocerite hardly longer than the antennular peduncle, 

 scaphocerite with the outer margin as strongly concave as in A. parvi-rostris, a little longer 

 than the antennular peduncle, terminal spine reaching backward to the distal extremity of the 

 first antennular article, while the blade extends to the middle of the third. In the female 

 of A. parvi-rostris the stylocerite reaches almost to the 2 nd third part of the second antennular 

 article and the blade extends to the tip of the antennular peduncle. 



Outer face of the merus of small cheliped 3-times (in the female of A. parvi-rostris 

 2,5-times) as long as broad, infero-internal margin with a long, slender spine at the far end, 

 exactly as in that species; chela almost 4-times as long as high, fingers very slightly longer 

 than the palm. In the female of A. parvi-rostris the small chela appears a little stouter, i. e. 

 higher with regard to its length, but for the rest agrees with the preceding. 



Ischium of 3" 1 and 4 th legs with a strong, movable spine. Merus of 3 rd legs unarmed, 



307 



