Abstract:
Two new records of free-living marine nematodes,
Comesoma bermudense and
Comesoma hermani, were found and described during the taxonomy and diversity study in the Jinhai Bay Mangrove Reserve, Beihai, Guangxi, in spring 2021.
C. bermudense is characterized by four cephalic setae 21-31 μm in length and four subcephalic setae 5-7 μm in length. Its cervical setae are arranged irregularly and transverse rows with lateral differentiation dotted on the cuticle. The buccal cavity is cup-shaped and posteriorly cuticularized. Amphid spirals 2.5 turns. Two spicules are equal, 187-192 μm in arc length, with no apophysis on the gubernaculum. The male has papillary precloacal supplements.The ratio of spicules to tail length is 0.7-0.9, longer than the type species (0.4-0.6) described by Jensen & Gerlach. The other species,
C. hermani is characterized by buccal cavity of two obvious chambers. The anterior chamber is cupshaped with cuticularized base and the posterior chamber is narrow. Amphid spirals 2.5 turns. Two slender needlelike spicules are equal, 187-192 μm in arc length, with no apophysis on the gubernaculum. There are setae before the cloaca. The male body length of the Jinhai Bay specimen is 2.2-2.4 mm, longer than the type species (1.7-2.1 mm) described by Chen & Vincx. These two species are first reported in the mangrove wetland.