PEREZ EARFANTE: AMERICAN SOLENOCERII) SHRIMPS 



A-D. 



FIGURE 26.— Haliporoides diomedeae, 9 45.5 mm cl, Valparaiso, Chile. A, Mandible. S, First maxilla. C, Second maxilla. D, First 



maxilliped. e, Arthrobranchia. e\ Enlargement of e (all from left sidel. 



of carpus in females. Pereopods increasing in 

 length from first to fifth; third and fourth extend- 

 ing distally for about same distance. First pereo- 

 pod with spine on basis and ischium, and one 

 movable distal spine and one or two fixed proximal 

 ones on merus; basis of second pereopod lacking 

 spine. In females, coxal plate of third pereopod 

 directed and broadening mesially, strongly con- 

 vex posteriorly. In both sexes, anteromesial spine 

 present on coxae of third through fifth pereopods; 

 in females, spine on third long, slender, and 

 situated anterodorsally to coxal plate, and spines 

 on fourth and fifth small and sharp; in males, 

 spines on third and fourth pereopods small and 

 sharp, but spine on fifth large, flattened, curved 

 laterally. 



Abdomen with middorsal keel from fourth 

 through sixth somites and strong, sharp spine at 

 posterior end of keel on each; sixth somite short, 

 about 1.25 times as long as high, bearing postero- 

 ventral spines. Telson with broad median sulcus 

 deep anteriorly, shallower posteriorly, ending at 

 level of base of lateral spines, and flanked by 

 well-defined ridges; terminal portion length 4-5 



times basal width, spines short, 1.0-1.65 times 

 basal width of terminal portion. Mesial ramus of 

 uropod reaching apex of telson or overreaching it 

 by about 0.15 of its own length; lateral ramus, 

 in turn, overreaching mesial by almost 0.2 of its 

 own length, armed with rather strong, sub- 

 terminal, distolateral spine. Third through fifth 

 pleopods in males bearing strong dorsomesial 

 ridge, that of third bearing distally strong sub- 

 rectangular tooth with minute tooth at its base; 

 ridge on fourth ending in also large, subtriangular 

 tooth; last three pleopods in females with barely 

 marked dorsomesial ridge. 



Petasma (Figure 27 'A, B) with row of cincinnuli 

 occupying only proximal 0.3 of median line; ter- 

 minal part of ventromedian lobule abruptly 

 broadening distally with terminal margin serrate 

 laterally; rib of dorsolateral lobule broad prox- 

 imally, its distal extremity reaching, but not 

 overreaching, margin of adjacent membranous 

 portion; distal part of ventrolateral lobule free, 

 forming roughly subelliptical flap diverging from 

 ventromedian lobule; ventral costa broad prox- 

 imally, tapering along margin of flap. 



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