Pseudosarcotretes, Yumura & Nishikawa & Ohtsuka, 2024

Yumura, Nanami, Nishikawa, Jun & Ohtsuka, Susumu, 2024, A New Species and a New Genus of the Family Pennellidae (Copepoda: Siphonostomatoida) Parasitic on North Pacific Lightfish Maurolicus japonicus (Actinopterygii: Stomiiformes: Sternoptychidae) Collected from Suruga Bay, Japan, Species Diversity 29 (1), pp. 81-90 : 83

Genus Pseudosarcotretes gen. nov.

Type species. Pseudosarcotretes sp. nov., fixed by the present designation.

Diagnosis. Female. Body elongated and straight, with reduced abdomen without brush-like structure. Cephalothorax with pair of lateral holdfasts with semicircular expansions. Oral cone on anteroventral tip in form of conically elongated proboscis. Neck comprising pedigers 1–3. Anterior part of trunk slightly narrow, posterior part cylindrical; caudal rami present. Egg string straight and uniseriate.

Antennule incompletely two segmented. Antenna well developed and subchelate, 3-segmented; second segment in form of stout process close to edge; third segment curved inward, forming subchela with preceding segment. Mandible short, with three teeth at tip. Maxillule simple, inner lobe with only one terminal seta; outer lobe absent.

Legs 1 and 2 biramous; leg 3 uniramous; rami distinctly 2-segmented; armature elements are shown in Table 2.

Male. Unknown.

Remarks. The new genus Pseudosarcotretes is defined by a combination of the following features: (1) a pair of cephalothoracic processes in the form of lobate lateral expansions, (2) elongated proboscis, (3) abdomen reduced, (4) the presence of distinct caudal rami, (5) legs 1 and 2 biramous and leg3 uniramous, and (6) leg 4 absent. Maxilla not observed and may have been lost during detaching from the host.

Adult females of Pseudosarcotretes gen. nov. shares some features with Cardiodectes , Protosarcotretes and Sarcotretes . Pseudosarcotretes differs from Cardiodectes in having elongated proboscis (vs. proboscis not formed); differs from Protosarcotretes in absence of leg 4 and endopod of leg 3; differs from Sarcotretes in having a distinct caudal ramus (vs. absent or as small swellings) and lacking leg 4 completely (vs. vestige). These differences and more detail information are shown in Table 3.

Etymology. The new generic name refers to pseudo - (Ancient Greek adjective, meaning counterfeit) and its closely related genus Sarcotretes . Gender masculine.