KONGL. SV. VET. AKADEMIENS ITANDLINGAR. BAND. 22. N:0 7. 321 



Hab. The tropical regions of the Atlantic. (D. M.; F. M.; P. M.; K. M.; S. M.; U. M.) 



Syn. 1887. Phronimopsis Sarsi, C. BOVALLIUS. "Systematical list of the Ampliipoda Hyperi- 



idea». Bih. t. K. Sv. Vet. Ak. Handl. 

 Bd. 11. N:o 16, p. 23. 



Of the hitherto known species of the genus Phronimopsis the present comes 

 nearest to the other forms of the family Hyperiidae in general habitus as well as in 

 the shape of the person. From its congeners it is distinguished b}^ the form of the urus 

 and its appendages. Phronimopsis tenella comes, however, extremely near to it in many 

 characteristics. 



I have examined only male specimens. 



The male. 



The body is slender; the integument is very thin and pellucid. The head and 

 perreon together are scarcely longer than the pleon. 



The head is broader than the pera3on, and about a fourth part deeper than long. 

 The antennal groove is very large, commencing above the middle of the front side. The 

 under side of the head is evenly rounded, with the epistoma a little protruding. 



The first pair of antenna? (PI. XIV, fig. 2 and 3) are about as long as the second. 

 The first joint of the peduncle is very thick and robust, and is about three times as 

 long as the two following joints together. The first joint of the flagellum is as long as the 

 whole peduncle, tapering towards the apex, with bulging sides, and is densely set with 

 long olfactory hairs; the second joint is tolerably thick, and almost a third part as long- 

 as the first; the lower front corner is produced into a cylindrical process, which is tipped 

 with two club-shaped hairs (PL XIV, fig. 3): the third joint is longer, but narrower, than 

 the second; the following joints are much longer, slender, cylindrical, and set with a few 

 short hairs on the under margin. The flagellar joints are sixteen or seventeen in number. 



The second pair of antenna? (PI. XIV, fig. 4 — 6) reach beyond the telson. The first 

 free joint is as long as the second, the third is almost as long as the two preceding to- 

 gether. The first joint of the flagellum is longer than the whole peduncle; the following- 

 are shorter, subequal in length, and each provided with a short hair at the middle. The 

 flagellar joints are sixteen or seventeen in number. 



The epistoma is obtusely conical, and unusually large. 



The labrum is symetrically bilobed, with a shallow incision at the middle. 



The mandibles (PI. XIV, fig. 7). The stem is slender, and somewhat constricted at the 

 middle; the incisive lamina is rounded, with five or six sharp teeth and two tufts of short 

 hairs at the base; the secondary lamina of the left mandible has five teeth; the molar 

 tubercle is very broad, like that in Euthemisto. The mandibular palp is slender with the 

 joints equal in length. 



The labium has the lateral processes rounded, and covered with short hairs. 



41 



K Sv. Vet. Akad. Handl. Band. 22. N:o 7. ^ l 



