Boone, Crustacea, Cruise of "Alva,'* 1931 169 



Color: Vivid orange red, with the tips of the ehelipeds usually 

 blackish brown. 



Technical description: Carapace lenticular, approaching the 

 quadrilateral, moderately convex in the males, the surface smooth, 

 shining, with no definition of the regions. The interorbital region is 

 equal to over half the greatest width of the carapace ; the frontal mar- 

 gin projects in advance of the preorbital angle and is cut into a pair of 

 submedian, small, triangular teeth, separated from each other by a tri- 

 angular sinus, subequal to one of the teeth, and from the outer pair of 

 teeth by a wider, uneven sulcus ; this outer pair of teeth are each about 

 twice as wide basally as each submedian tooth and are blunted distally 

 with the margin finely denticulate or in some specimens smooth, not 

 quite as far advanced as the inner pair of teeth ; the outer angle nearly 

 right-angled, separated by a wide, V-shaped incision from the blunted, 

 or sometimes rounded, dentiform, preorbital tooth. The orbital mar- 

 gin is smooth, unbroken ; the postorbital angle acute ; the inferior or- 

 bital margin is also smooth and terminates in an acute, conical spine at 

 the inner angle. The lateral margins of the carapace are convex, with 

 an acute spine or tooth at the union of the anterior and postlateral 

 areas, and convergent posteriorly. The posterior margin is short, 

 slightly sinuate. The pterygostomian region is smooth. 



The ehelipeds are subequal in young males and females, moderately 

 unequal in large males; about two and one-half times as long as the 

 carapace in females and two and three-fourths to three times as long 

 as the carapace in the large males. The ischium is strong ; the merus 

 trigonal, with an acute tooth at the inferior anterior distal angle, and 

 the upper surface foliaceous with a laminate, rounded elbow proxi- 

 mally at the upper posterior margin ; the anterior lateral margin ser- 

 rate with five, sometimes six teeth, the distal margin with one triangu- 

 late tooth in addition to the distal marginal tooth; the carpus is 

 rounded and bears one tooth at the inner angle; the palm is three- 

 fourths as high as long, very compressed, with the outer surface 

 slightly convex ; the upper half with abundant, thick, short setae, the 

 lower margin cristate. The lower finger is triangular with curved tip, 

 about one-half as long as the palm, with rudimentary dentition; the 

 upper finger is very curved, fitting closely upon the lower finger, also 

 has rudimentary dentition ; the curved tips of the two fingers cross. 



The ambulatories are slender, decreasing in length in the order 1, 2, 

 3, 4, each having the propodal-dactylar joint reinforced by a rounded 

 process, projecting from the posterior side of the distal margin of the 



