Two new species of the genus Caligus (Crustacea, Copepoda, Siphonostomatoida) from the Sea of Japan, with a note on the establishment of a new species group

Abstract

Two new species of Caligus are described from the Japanese coast of the Sea of Japan. Caligus chinglonglinisp. nov. is based on a male specimen found in a plankton sample, whereas C. kajiisp. nov. was collected from the body surface of the host flathead Platycephalus sp. These two new species can be assigned to a distinct species group, the pseudorhombi group newly named and defined by the morphology of the genital complex in both sexes, and by the structure and armature of legs 2 and 4. The species group so far accommodates 19 species including these two new species. The morphology, host specificity and zoogeography of the species group are discussed herein and keys to species groups of Caligus and to species of the C. pseudorhombi species group are provided.

Sea lice (Copepoda: Caligidae) from South Africa, with descriptions of two new species of Caligus

“…The phylogenetic analysis undertaken here was not designed to test these species-groups so that, for example, C. pelamydis is the only representative of the C. diaphanus-group (see Boxshall, 2018) included in the analysis and, similarly, C. dakari is the only representative of the C. productus-group (see Boxshall & El-Rashidy, 2009). No representatives of the C. bonito-group (see Boxshall, 2018), the C. confususgroup (see Boxshall, 2018), the C. pseudorhombigroup (see Ohtsuka & Boxshall, 2019), or the C. undulatus-group (Ohtsuka et al, 2020) were included. However, several species belonging to the C. macarovi-group, first proposed by Boxshall & Gurney (1980), are included in the taxon set.…”

Caligus madeirensis sp. nov. (Copepoda: Caligidae) Parasitic on Pompano, Trachinotus ovatus (Linnaeus, 1758), from Eastern Atlantic Waters, Surrounding the Madeira Archipelago, Portugal

“…nov, is the possession of an accessory process on all 3 outer terminal spines on the oblique distal margin of the second exopodal segment of leg 1. Including the three recently described new species, C. adanensis Özak, Sakarya & Boxshall, 2019, C. chinglonglini Ohtsuka & Boxshall, 2019, and C. kajii Ohtsuka & Boxshall, 2019, the number of valid species within the genus Caligus is now 270 [ 30 , 33 ]. To our knowledge, among these 270 species only the following four species: C. amblygenitalis Pillai, 1961, C. berychis Wilson C.B., 1936, C. rufimaculatus Wilson C.B., 1905, and C. sibogae Boxshall & Gurney, 1980 share this unusual character state with C. madeirensis sp.…”

First record of Caligus dussumieri Rangnekar, 1957 (Copepoda, Siphonostomatoida, Caligidae) from Malaysia, with notes on caligids found from Malaysia and on host-specificity of caligids on lutjanid fishes

“…Seven species groups have been established within the genus Caligus : the bonito -, confusus -, diaphanus -, macarovi -, productus -, pseudrorhombi - and undulatus -groups ( Boxshall 2018 , Ohtsuka and Boxshall 2019 , Ohtsuka et al 2020b ). The bonito -group can be recognised on the basis of the following features: well-developed inner setae on the distal exopodal segment of leg 1 and the presence of a row of robust denticles along the outer margin of the second endopodal segment of leg 2.…”