Pseudochaenichthys georgianus Norman 1937

• Main Authors: Kuzmina, T. A., Salganskiy, O. O., Vishnyakova, K. O., Ivanchikova, J., Lisitsyna, O. I., Korol, E. M., Kuzmin, Yu. I.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2022
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Actinopterygii; Perciformes; Channichthyidae; Pseudochaenichthys; Pseudochaenichthys georgianus; Icefish
• Online Access: https://doi.org/10.5281/zenodo.7171906; http://treatment.plazi.org/id/FD5D87DFED5CFFA4FF20FE53FCAEF8F8

Pseudochaenichthys georgianus In the South Georgia icefish, 16 helminth species were recorded (from 3 to 12 species per host), including 3 species of trematodes, 4 species of cestodes, 5 species of nematodes and 4 species of acanthocephalans (table 3). Estimated species richness was 18 (Chao1), 19 (jackknife) or 17 (bootstrap) species. The diversity indices equalled 1.54 (Shannon), 0.68 (Simpson), and 0.55 (Pielou’s evenness). All the cestode species, as well as the nematodes Anisakis sp., Contracaecum sp. and Pseudoterranova sp. and acanthocephalans Corynosoma spp. parasitize P. georgianus on larval stages. Thus, P. georgianus is considered to be a definitive host for 6 out of 16 helminth species recorded. As in the mackerel icefish, cestodes predominated in the helminth community of P. georgianus together they comprised 78.7 % of the total helminth number (fig. 1). According to the prevalence of infection, 8 species predominated in the helminth community in P. georgianus (table 3). Bilocular and trilocular metacestodes had an infection prevalence higher than 95 %. The cestode Diphyllobothrium sp., the trematodes M. pennelli and N. georgiensis , the nematodes Contracaecum sp. and Pseudoterranova sp. had an infection prevalence of 70–95 %. The nematode D. fraseri and monolocular metacestodes were common, with the infection prevalence of 36.4 % and 45.5 %, correspondingly. Other 8 species of helminth occurred in less than 30 % of examined P. georgianus. In all three latter fish species, the proportion of helminth species found on larval stages was larger (62.5–75 %) than that of the species represented by adult parasites (25–37.5 %) (fig. 2). The helminth species richness appeared to be much higher in fishes from shallowwater (10–30 m deep) habitats than in deep-water (60–800 m) habitats (table 4). Analysis of similarity between helminth faunas in studied samples of shallow- and deepwater fishes (table 5) revealed the highest similarity of helminth faunas in two shallow-water species from the Ukrainian ...