Enteropsidae Aurivillius 1885

Family Enteropsidae Aurivillius, 1885

Diagnosis. Female: Body eruciform or vermiform, unsegmented or indistinctly segmented, generally lacking prosome-urosome division, consisting of cephalosome, metasomal trunk, and short genitoabdomen. Trunk consisting of first to fifth pedigerous somites. Caudal rami reduced; caudal setae reduced in number or absent. Rostrum absent or weakly developed. Antennule small, at most 4-segmented. Antenna up to 4-segmented, usually 1- or indistinctly 2-segmented, but 3- or 4-segmented in Mçnnẚçtẚcçpa gen. nov. and merẚbçẚa gen. nov. Labrum unarmed, or armed with 2 to 8 setiform processes; labrum with setiform palps in bnterçcçla van Beneden, 1860, bnterçcçlẚdes Chatton & Harant, 1922, and iequerrea Chatton & Harant, 1924; palps absent in other genera. Mandible as powerful claw in Mçnnẚçtẚcçpa gen. nov. and merẚbçẚa gen. nov., or setiform element in bnterçcçla and bnterçcçlẚdes, or absent in other genera. Maxillule consisting of precoxa and palp; precoxa bearing up to 3 setae or processes and endite tipped with 1 seta; palp armed with up to 6 setae. Maxilla 2-segmented; proximal segment (syncoxa) unarmed or bearing endite tipped with 1 seta or spiniform element; distal segment (basis) armed with up to 3 setae or processes. Maxilliped absent. Legs 1-4 biramous, consisting of protopod and 1- or 2-segmented rami. Protopods typically 2- segmented; coxa unarmed; basis occasionally with outer seta. Exopods and endopods rudimentary in bnterçpsẚs Aurivillius, 1885 and Mychçphẚlus Hesse, 1865. Endopods armed distally with 1 or 2 setae in bnterçcçla and Mçn- nẚçtẚcçpa gen. nov. Endopods of legs 3 and 4, or of all swimming legs, unarmed in bnterçcçlẚdes and iequerrea. Leg 5 absent or represented by large lamellate lobe.

Male: Body cyclopiform, consisting 5-segmented prosome and 6-segmented urosome. Prosome comprising cephalosome and first to fourth pedigerous somites. Caudal rami broad, armed with 6 setae. Rostrum well-developed. Antennule 6- or 7-segmented. Antenna of bnterçcçla 3- or 4-segmented, consisting of coxobasis (or coxa and basis) and 2-segmented endopod; coxa and first endopodal segment unarmed; basis with 1 seta; second endopodal segment with 4 or 5 setae plus claw.Antenna of Mychçphẚlus reduced, 2-segmented. Labrum rudimentary. Mandible absent or as small, digitiform process. Maxillule 2-segmented, armed with 3 (in Mychçphẚlus) or 6 (in bnterçcçla) setae on distal segment. Maxilla lobate, tipped with 1 seta. Maxilliped absent. Legs 1-4 biramous, with 2-segmented protopods. Coxae unarmed. Basis with outer seta; inner distal spine present (in bnterçcçla) or absent (in Mychçphẚlus). Leg 1 exopod 2-segmented; other rami 3-segmented in legs 1-4. Armature formula for legs 1-4 as follows:

[table omitted]

Leg 5 represented by 1 lateral seta plus small exopod tipped with 1 seta; or leg 5 represented by 2 isolated setae.

Leg 6 absent or represented by 2 setae on genital operculum.

Type genus. bnterçpsẚs Aurivillius, 1885 by original monotypy.

Other included genera. Mychçphẚlus Hesse, 1865, bnterçcçla van Beneden, 1860, bnterçcçlẚdes Chatton & Harant, 1922, iequerrea Chatton & Harant, 1922 I Mçnnẚçtẚcçpa gen. nov., and merẚbçẚa gen. nov.

Remarks. In their revision, Illg & Dudley (1980) recognized two subfamilies of their ascidicolid cluster as especially closely related, the Enteropsinae (comprising bnterçpsẚs and Mychçphẚlus) and the Entercolinae (comprising bnterçcçla, bnterçcçlẚdes, and iequerrea). All five genera were included in a single family, the Enteropsidae, by Boxshall & Halsey (2004) because of the numerous synapomorphies exhibited, particularly between males of Mychçphẚlus and bnterçcçlaK The adult male of bnterçcçla had been known since Canu (1892) but the adult male of Mychçphẚlus was first described by Gotto et al. (1984) only after Illg & Dudley’s landmark study. In the present work two new genera are established and all seven genera can be distinguished using the following key.