CAPRELLIDAE OF WESTERN NORTH ATLANTIC 65 



Ileiniproto, new genus 



Flagellum of antenna 2, 2- to 4-segmented, swimming setae absent; 

 mandibular palp 3-segmented, setal formula for terminal article 1-1 

 or 1-x-l, molar absent; outer lobe of maxilliped equal to inner lobe; 

 gills on pereonites 2-4; pereopods 3 and 4, 6-segmented, pereopod 

 5, 5-segmented; abdomen of male with 2 pairs of small uniarticulate 

 appendages and pair of nonsetose lobes, female with 1 pair of 

 uniarticulate appendages. 



Type-species: Ilemiproto wigleyi, new species (by present 

 designation). 



Remarks. — This new genus is closely related to Proiomina Mayer, 

 1903, in that the males of both genera have 2 pairs of abdominal 

 appendages; however, in Proiomina the appendages are biarticulate 

 and positioned near the posterior part of the abdomen and in Hemi- 

 proto the appendages are uniarticulate, one positioned near midlength 

 and one anteriorly. 



Another character which these genera share is the elongation of 

 the carpus of gnathopod 2. This character is not unique to the 2 

 genera since a slight elongation occurs in Phtisica antillensis and is 

 probably not of genei'ic significance. 



Flemiprofo lacks a molar on the mandible; however, Mayer did not 

 describe all of the mouthparts for his species, including Proiomina. 

 Since specimens of Proiomina are not available to me, I cannot be 

 certain that this character is useful for separating these 2 genera. 



The generic name is a combination of Greek terms, "hemi" meaning 

 half, referring to the number of articles in the abdominal appendages 

 as compared with Phtisica and Proiomina, and "protos" meaning 

 first, which was the original name previously used for Phtisica. 



Ilemiproto tvigleyi, ncAV species 



Figures 31, 32c-e, 50 



Diagnosis. — Since this genus is monotypic, the characters of the 

 genus are diagnostic for the species. 



Description. — Male holotype: Body smooth. Length 7.5 mm. 



Antenna 1 approximately length of body, flagellum of 9 articles. 

 Antenna 2 approximately as long as articles 1 and 2 of anteiuia 1, 

 flagellum of 4 articles. 



Mouthparts as in Phti/^ica marina except setal formula for terminal 

 article of mandibular palp 1-2-1 and outer lobe of maxilla 1 with 4 

 extremely toothed spines and 2 nontoothed spines. 



Propodus of gnathopod 1 triangular with 4 proximal grasping spines, 

 1 large and slightly proximal to others, grasping margin finely serrate; 

 dactylus not serrate. Propodus of gnathopod 2 with 3 grasping spines, 

 1 large and slightly proximal to others, grasping margin with numerous 



