Caecoserolis Wägele, 1994

Bruce, Niel L., 2008, Two new deep­water species of Caecoserolis Wägele, 1994 (Isopoda, Sphaeromatidea, Serolidae) from off North Island, New Zealand *, Zootaxa 1866, pp. 453-466 : 454

Caecoserolis Wägele, 1994

Caecoserolis Wägele, 1994: 10 , 50, 55.— Poore & Brandt, 1997: 161.

Type species: Serolis brinki Kensley, 1978 , original designation ( Wägele 1994).

Remarks. Poore and Brandt (1997) gave a revised diagnosis to Caecoserolis , and discussed some of the difficulties presented by the serolid genera recently established by Brandt (1988, 1991) and Wägele (1994). Those issues are not reappraised here, and the two new species described here are considered to generally accord well with the genus sensu Poore and Brandt (1997), but more particularly ally closely with Caecoserolis novaecaledoniae Poore and Brandt, 1997 rather than with the type species, Caecoserolis brinki ( Kensley, 1978) .

Caecoserolis brinki differs notably from the other species currently placed in the genus in having considerably broader antennal peduncular article 5 (less than 5.0 times as long as greatest width compared to more than 8.6–10.3 times as long as greatest width for other species currently placed in the genus), a posteriorly rounded and apparently dorsally flat (lacking median or sublateral carinae) pleotelson, and the coxal plates of pereonite 6 not extending posteriorly beyond the pleonites. Expanded antennule peduncle articles 4 and 5 is an infrequent character state within the family that also occurs in Thysanoserolis Brandt, 1991 and Glabroserolis Menzies, 1962 ; that state could be of sufficient significance to warrant separation of the type species from those others in the genus which lack this presumed derived character state, but have coxae 6 extending posteriorly beyond the pleonites.

The generic placement of the very briefly described Caecoserolis monodi ( Cals, 1979) is be regarded as uncertain as the pleotelson shape appears unique within the family and the dorsolateral insertion of the uropods is not consistent with that of the type species or other species of the genus, which is ventrolateral. The type material for this species is not held at the Muséum national d’Histoire naturelle in Paris, and deposition of the material was not indicated by Cals (1979). The whereabouts of the type material is at present unknown. Although not discussed by Poore and Brandt (1997) Serolis antarctica Beddard, 1884 (see figures in Schotte 1992) is sufficiently similar to warrant inclusion, and that species is here transferred to Caecoserolis .

Species included in Caecoserolis : C. apheles ( Schotte, 1992) , C. bicolor sp. nov., C. brinki ( Kensley, 1978) type species, C. carinata sp. nov., C. novaecaledoniae Poore and Brandt, 1997 , and provisionally C. antarctica ( Beddard, 1884a) comb. nov.—a probable species complex with attributed specimens from the southern Indian Ocean, tropical western Atlantic off Brazil, and tropical western Indian Ocean (see Beddard 1884b, Schotte 1992). Excluded from the genus is Serolis monodi Cals, 1979 , here regarded as incertae sedis.