THOMPSONIIDAE HØEG & RYBAKOV, 1992

Høeg, Jens T., Noever, Christoph, Rees, David J., Crandall, Keith A. & Glenner, Henrik, 2020, A new molecular phylogeny-based taxonomy of parasitic barnacles (Crustacea: Cirripedia: Rhizocephala), Zoological Journal of the Linnean Society 190, pp. 632-653 : 645

FAMILY THOMPSONIIDAE HØEG & RYBAKOV, 1992

Type genus: Thompsonia Kossmann, 1874 .

Type species: Thompsonia globosa Kossmann, 1874 .

Diagnosis (amended): By molecular data. Morphology-based characters are numerous globular or club-shaped colonial externae without receptacles that emerge simultaneously from the host. and each releases only a single brood. These externae are replaced through several generations of new externae that often appear in increasing numbers. The cyprids carry one bifurcated seta and some smaller setae and structures apically on the fourth segment. The second pair of lattice organs is not different from the remaining four pairs.

H o s t s: A n o m u r a, B r a c h y u r a, C a r i d e a a n d Stomatopoda.

Genera: Diplothylacus Høeg & Lützen, 1993 (four spp.), Jensia Boyko & Williams, 2015 (two spp.), Thompsonia (five spp.) amd Thylacoplethus Coutière, 1902 (13 spp.).

Remarks: The family comprises taxa that originate at node 13 in Figure 3. The family is monophyletic in all relevant analyses based on molecular data. Jensia was formerly named ‘ Pottsia ’ Høeg & Lützen, 1993, but this was a preoccupied name (see Hiller et al., 2015). Høeg & Lützen (1993) gave an extensive account of the systematics, morphology and phylogeny of this family, and to this is added the paper by Hiller et al. (2015). Among all Rhizocephala, Thompsoniidae have the widest taxonomic range of host animals.

FAMILY CHTHAMALOPHILIDAE BOCQUET-VEDRINE, 1961

Type genus: Chthamalophilus Bocquet-Vedrine, 1957 .

Type species: Chthamalophilus delagei Bocquet-Vedrine, 1957 .

Diagnosis (amended): By molecular data. Morphology-based diagnosis amended from Høeg & Rybakov (1992) is cypris larvae being minute (<100 µm long) and completely lacking a thorax, whence they can move only by walking on the antennules. The fourth segment is reduced to a mere rudiment. The cypris carapace is furnished with only four long setae located posteriorly. The externa is always surrounded by a double layer of cuticle separated by a fluid filled space, rendering the externa surface distinctly refringent. The male organs are invaginated from the mantle into the mantle cavity as free-floating bodies enveloped in cuticle. These ‘primary spermatogenic islets’ later split into several ‘secondary islets’ devoid of cuticle and in which spermatogenesis proceeds ( Høeg et al., 1990, 2019).