no. 3641 STOMATOPOD CRUSTACEA — MANNING 35 



ventral projections overhanging articulation of uropod, each armed 

 with accessory spinule; ventral surface of sixth abdominal somite 

 unarmed. 



Telson broader than long, with normal dorsal fan of 5 teeth; mar- 

 ginal armature consisting of, on either side of the midline, 1 movable 

 submedian tooth and 4 fixed teeth, inner overhanging movable sub- 

 medians; 6-7 submedian denticles present, with 1 denticle present 

 between each of the other marginal teeth. 



Uropod with 7 slender movable spines present on outer margin of 

 proximal segment of exopod, last extending to midlength of distal 

 segment; 9-13 stiff setae present on inner distal lobe of proximal 

 segment of exopod; endopod triangular, with prominent fold on 

 inner, proximal margin; spines of basal prolongation trefoil in cross 

 section, inner longer than outer. 



Color. — Kostral plate, eyestalks, anterior appendages, and dorsal 

 surface of claws with scattered dark spots; carapace with 3 transverse 

 black bands plus dark crescent at each posterolateral angle; last 3 

 thoracic and all 6 abdominal somites with broad, transverse black 

 band; telson with 4 oval dark patches, interrupted at midline and 

 between second and third dorsal teeth on each side; uropodal exopod 

 with black spot at articulation of distal segment, inner angle of distal 

 segment dark; endopod black. 



Size.— Only male known, TL 63.2; females, TL 62.5-64.5. Other 

 measurements of female paratype: carapace length 10.6; cornea width 

 1.6; rostral plate length 3.1, width 3.4; fifth abdominal somite width 

 11.1; telson length 5.0, width 8.8. 



Discussion. — A. canthosquilla humesi can be distinguished from 

 both A. acanthocarpus (Miers) and A. multifasciata (Wood-Mason) 

 by the presence of four fixed marginal teeth on the telson; the latter 

 two species both have but two fixed spines. Acanthosquilla humesi 

 agrees with A. tigrina (Nobili) and A. vicina (Nobili) in having four 

 pairs of fixed marginal teeth on the telson but may be readily dis- 

 tinguished from both of those species. It lacks the posterior ventral 

 spines on the sixth abdominal somite that are characteristic of A. 

 tigrina, and it differs from A. vicina in having a single median spine 

 on the rostral plate, fewer spines on the claw (seven instead of 10-11), 

 and in having the submedian denticles of the telson arranged in a 

 transverse row rather than in a semicircle. 



These specimens were the hosts of a cyclopoid copepod, Hemicyclops 

 acanthosquillae Humes, collected and described by Arthur G. Humes 

 (1965). This, I believe, is the first recorded occurrence of a copepod- 

 stomatopod association. 



Humes (1965, p. 184) noted that the stomatopods appeared in the 

 water seeping into a hole 30 cm deep that had been dug in clear sand. 



