VALVIFERA • IDOTEIDAE 255 



Thermarcturus Paul and Menzies, 1971 



DIAGNOSIS Pereonite 1 not fused with cephalon. Pereonite 4 subequal in 

 length to pereonite 3, not markedly elongate. Pereopods 2—4 having dactyli 

 but lacking elongate setae. Body cylindrical, flexed between pereonites 4 and 

 5. Pleon consisting of two free pleonites plus pleotelson. 



Thermarcturus venezuelensis Paul and Menzies, 1971 

 Figure 107H 



DIAGNOSIS 9 4.5 mm. Cephalon, all pereonites, and anterior two pleonites 

 each with submedian pair of dorsal tubercles, those on pereonites 2 and 3 

 broad and expanded. Pleonite 2 with pair of bulbous lateral swellings, pos- 

 terior margin triangular. Pleotelson with lateral shoulder anteriorly, posteri- 

 orly triangular. 



RECORDS Ofl~ Venezuela, 95 m. 



REMARKS Only the holotype (which seems to be lost) is known of this spe- 

 cies. Considerable uncertainty exists regarding some of the features. 



Family Idoteidae Fabricius, 1798 

 Subfamily Idoteinae Dana, 1852 



DIAGNOSIS Flagellum of antenna either multiarticulate; clavate, i.e., with 

 large basal articles and with or without one to four reduced distal articles; or 



Key to genera of Idoteinae 



1. Antennal flagellum multiarticulate Idotea 



Antennal flagellum clavate 2 



2. Pereopod 4 reduced, considerably smaller than pereopods 3 or 5 .... 3 

 Pereopod 4 not reduced, of similar size to pereopods 3 and 5 



Erichsonella 



3. Pleon consisting of three complete and one incomplete pleonites plus 



pleotelson Cleantioides 



Pleon consisting of two complete and two incomplete pleonites plus 

 pleotelson Miratidotea 



