REVISION OF RECENT BAIRDIIDAE 87 



Bythocypris Brady, 1880 



Bythocypris Brady, 1880, p. 45. — Brady and Norman, 1889, p. 119. — Muller, 1894, 

 p. 275.— Sars, 1923, p. 6.— Morkhoven, 1963, p. 37. 



Type-species. — Bythocypris reniformis Brady, 1880, p. 46, pi. 5, 

 fig. la-1. 



Diagnosis. — Carapace moderately robust, smooth, lateral outline 

 oblong to subreniform, cyprid in aspect; muscle-scar pattern an 

 anterior row of 3 scars plus one posteroventral scar, scars often 

 divided. 



Antennule with setae no longer than total of podomeres, antennae 

 relatively stout, podomere 6 \nth long distal claw and 3 or 4 smaller 

 setae; vibratory plate of first thoracic leg oval, ^vith 6-15 long un- 

 feathered setae and 5 or more shorter feathered setae; furca with 3 

 long setae and 3 or 4 shorter setae; maxillar plate with 8-10 unfeathered 

 posteroventral setae. 



Included species. — Recent species whose soft parts have been 

 described, listed by original binomen: 



Bythocypris reniformis Brady, 1880 

 Bairdia bosquetiana Brady, 1866 

 IBairdia complanata Brady, 1867 

 Bairdia ohtusata Sars, 1866 

 Bythocypris elianina, new species 

 Bythocypris spiriscutica, new species 



Recent species assigned to Bythocypris on carapace features only 

 include: 



Bairdia abyssicola Brady, 1880 

 Bairdia affinis Brady, 1886 

 Bythocypris (?) compressa Brady, 1880 

 Bythocypris elongata Brady, 1880 

 Bairdia folini Brady, 1886 

 ^Bythocypris laeva Puri, 1953 

 Bythocypris lucida Seguenza of Ascoli, 1964 

 Bythocypris mozambiquensis, new species 

 Bythocypris prolata, new species 



Affinities. — The soft parts of Bythocypris ristain flexibility of 

 morphology in several characters where the comparable structure 

 in species of '^Bairdia'' is of a rigidly estabhshed type. This greater 

 variability renders the genus difficult to diagnose but easy to recognize. 

 This difficulty is compounded by current ignorance of the male 

 soft-part anatomy; the males described below for two new species 

 represent the first males known in Bythocypris. 



The thin-shelled abyssal forms described below differ somewhat 

 in appendage structures as well and perhaps should be separated as 

 another taxon. The distinction between Bythocypris and Zabythocypris 

 is chiefly one of degree. 



