Kerry A. Hadfield

Review of the fish parasitic genus Ceratothoa Dana, 1852 (Crustacea, Isopoda, Cymothoidae) from South Africa, including the description of two new species.

Abstract The genus Ceratothoa Dana, 1852 is revised for South African waters and re-diagnosed. Ceratothoa retusa (Schioedte & Meinert, 1883) is recorded from the eastern coast, and Ceratothoa africanae sp. n. and C. famosa sp. n. are described; C. imbricata (Fabricius, 1775) and C. trigonocephala (Leach, 1818), are redescribed, revised and excluded from the South African fauna. Ceratothoa africanae sp. n. can be distinguished by the stout body shape of the female; triangular cephalon with a pointed rostrum; short uropods which do not extend past the pleotelson; large carinae on the pereopod basis; a broad pleon; and large medial lobes on female pleopods. Ceratothoa famosa sp. n. is characterised by the long rectangular body shape; pereonite 1 with a raised medial protrusion; narrow antenna with antennule article 1 expanded; uropods which reach the posterior margin of the pleotelson; narrow rami on uropods; and no appendix masculina on pleopod 2 of the male specimens.

Life cycle of the temporary fish parasite, Gnathia pilosus (Crustacea: Isopoda: Gnathiidae) from the east coast of South Africa.

The life cycle of the South African gnathiid isopod, Gnathia pilosus , was studied using the common east coast tidal pool fish, Scartella emarginata and Antennablennius bifilum as hosts. Laboratory studies observing the feeding ecology of these temporary ectoparasites determined that the second and third unfed larval stages (zuphea larvae 2 and 3) took an average of 3 hours 52 minutes and 4 hours 19 minutes to feed respectively. After feeding, the second stage fed larvae (praniza 2) took 35 days to moult into the third zuphea form. Male and female praniza 3 larvae could be discerned before their final moults into adults which took place approximately 42 and 48 days respectively after their blood meals. Fertilization occurred within 24 hours after the female had completed her moult. It was thus estimated that the complete life cycle from the first larval stage to adult took between 134 to 140 days in water temperatures ranging between 20°C and 25°C. The length for this life cycle is unexpectedly long for gnathiids living in subtropical waters and may indicate that water temperature is not always the main factor in determining the duration of gnathiid life cycles.

Description of a new gnathiid, Afrignathia multicavea gen. et sp. n. (Crustacea : Isopoda : Gnathiidae), from South Africa

ABSTRACT A new genus and species of gnathiid isopod, Afrignathia multicavea gen. et sp. n., is described from material collected during the 1960s and 1970s in False Bay, offshore between Still Bay and Mossel Bay, and off Cape Point. This gnathiid does not conform to any other known species, having morphological characteristics not seen in the other 11 recognized genera. Features making the genus unique include a pylopod consisting of only one article, a mandible with two rows of unequal teeth on the blade and apex, and cephalosome appendages that could be maxillae 1 (maxillules), which are usually absent in all known male gnathiids. This species is also characterized by clusters of sensory pits scattered over the cephalosome and pereon.

Redescription of poorly known species of Ceratothoa Dana, 1852 (Crustacea, Isopoda, Cymothoidae), based on original type material

Abstract Due to the difficulty in accurately identifying cymothoids, these parasitic isopods are often incorrectly named or confused with other species. Within the genus Ceratothoa, a number of recent studies have aimed at clarifying some of the problematic species; however, several of the less studied species still require revision. This paper redescribes, from type material, several poorly known Ceratothoa species including Ceratothoa angulata, Ceratothoa capri, Ceratothoa carinata, Ceratothoa collaris, Ceratothoa gilberti, Ceratothoa gobii, Ceratothoa guttata, Ceratothoa italica, Ceratothoa oestroides, and Ceratothoa verrucosa, further resolving taxonomic uncertainties within the genus.

Elthusa winstoni sp. n. (Isopoda, Cymothoidae), a new fish parasitic isopod from Hawaii

Abstract The new cymothoid species, Elthusa winstoni sp. n., a branchial parasite of fishes from the family Acanthuridae Bonaparte, 1835 in Hawaii, is described and figured. The female adults can be distinguished by the strongly vaulted body and compacted body shape; rostrum with a small median point; short antennae which are close together (only 6 articles in both antennula and antenna); short and wide uropods extending to half the length of the pleotelson; short dactyli on pereopod 7; and large recurved robust setae on the maxilla. This is the first record of an Elthusa Schioedte & Meinert, 1884 species from the Hawaiian Islands and only the fifth cymothoid described from this region.

Revision of the fish parasitic genus Pleopodias Richardson, 1910 (Isopoda, Cymothoidae), with the description of a new species and key to the genus

Abstract The cymothoid genus, Pleopodias Richardson, 1910, is revised and a new species from South Africa is recorded. Pleopodias nielbrucei sp. n. can be distinguished by large eyes covering majority of the cephalon (almost in contact), antennula bases wide apart, antenna extending to middle of pereonite 2, subtruncate pleotelson, pereopod 7 with numerous acute robust setae on the propodus as well as the carpus, and the uropod exopod longer than the endopod. The three known species, Pleopodias diaphus Avdeev, 1975; P. elongatus Richardson, 1910; and P. vigilans Richardson, 1911 are also redescribed. Pleopodias nielbrucei sp. n. differs from these known species in both morphological characters as well as geographical distribution. A key to the Pleopodias species is provided.

Molecular assessment of three species of Anilocra (Isopoda, Cymothoidae) ectoparasites from Caribbean coral reef fishes, with the description of Anilocra brillae sp. n.

Abstract A morphological review and molecular characterization of Anilocra haemuli Bunkley Williams & Williams, 1981, were completed using specimens collected from Haemulon flavolineatum Desmarest, 1823 (French grunt) and Epinephelus guttatus Linnaeus, 1758 (red hind). Molecular and morphological data suggest that the isopods parasitizing H. flavolineatum and E. guttatus are different species. The specimens collected from E. guttatus are recognized as a new species, Anilocra brillae sp. n. Differences between Anilocra brillae sp. n. and A. haemuli include but are not limited to the pleonites 1–3 of A. brillae sp. n. being wider than 4–5 and 4–5 subequal, whereas the pleonites 1–2 of A. haemuli are wider than 3–5, and 3–5 are subequal. The seventh pereopod of A. brillae sp. n. is proportionally larger, has more robust setae, and the setae are distributed more extensively over the articles when compared to A. haemuli. Additionally, this study provides the first genetic characterization of three Anilocra spp. from the Caribbean, and is based on mitochondrial cytochrome c oxidase subunit gene (COI) for A. haemuli from H. flavolineatum, A. brillae sp. n. from E. guttatus, and A. chromis Bunkley Williams & Williams, 1981 from Chromis multilineata Guichenot, 1853.