172 U.S. NATIONAL MUSEUM BULLETIN 2 60 



Relationship. — This species resembles P. houvieri more than P. 

 longicaudatus by virtue of the dactyls of its pereopods being complexly 

 armed but it has many differences from P. houvieri., as follows: the 

 shape of the head, with its anterior keel extending ventrally from and 

 defining the limits of the rostrum and projecting beyond the distinct, 

 quadrate lateral cephalic lobes ; the weakness of the pleonal serrations ; 

 the absence of a posteroventral tooth on pleonal epimeron 1 ; the poorly 

 developed, nonquadrate posterior lobe of coxa 3; the short coxa 4; 

 the longer tooth of pleonite 5 ; the shorter outer rami of uropods 1 and 

 2 ; the anteriorly beveled coxa 1 ; and the shortness of pereopods 3-5 

 with their short fifth articles. 



Article 2 of gnathopod 2 of P. fervicax has only three anterior setae 

 compared to the numerous setae of that article on gnathopod 1. The 

 mouthparts are similar to those figured for P. longicaudatus by Pirlot 

 (1934) but articles 1 and 3 of the mandibular palp are longer (see fig. 

 84) and the ratios of spines on maxilla 1 differ, the inner lobe having 12 

 setae, the outer 9 spines, and the apex of palp article 2 with only 6 

 stout spines (plus the usual subterminal thin spines shown by Pirlot). 

 Pereopod 1 is longer and more strongly spinose than is pereopod 2. 

 The apices of the rami of uropod 3 are damaged. 



Syrrhoites Sars 



Key to the Species of Syrrhoites 



1. Pleonite 3 bidentate dorsally S. serrata (Sars) 



Pleonite 3 unidentate or iintoothed dorsally 2 



2. Pleonite 5 untoothed 3 



Pleonite 5 with distinct tooth 4 



3. Dorsal carina and teeth commencing strongly on pereonite 5, pleonal epimeron 



3 with medium sized acute posteroventral tooth. 



S. sorpresa (J. L. Barnard) 



Dorsal carina and teeth commencing weakly on pereonite 6. pleonal epimeron 



3 quadrate posteroveutrally, with minute tooth . S. lenella K. H. Barnard 



4. Pleonal epimeron 2 rounded posteroveutrally 5 



Pleonal epimeron 2 quadrate posteroveutrally or with minute tooth . . 7 



5. Pleonal epimeron 3 prolonged posteroventrally but lacking distinct tooth. 



S. walkeri Bonnier 

 Pleonal epimeron 3 with distinct, small posteroventral tooth 6 



6. Dorsal carina and teeth commencing strongly on pereonite 2. 



S. lorida (J. L. Barnard) 

 Dorsal carina and teeth commencing weakly on pereonite 6. 



S. cohasseta, new species 



7. Peduncles of uropods 1 and 2 lacking distolateral processes 8 



Peduncles of uropods 1 and 2 bearing distolateral processes 9 



8. Telson cleft less than halfway S. redox, new species 



Telson cleft more than halfway S. icrceris J. L. Barnard 



