Hoplolaimoidea (Nematoda: Tylenchida) from the Aleutian Islands with Descriptions of Four New Species


  • E. C. Bernard


Four new species of hoplolaimoid nematodes (Merlinius adakensis, Pratylenchoides megalobatus, Pratylenchus pratensisobrinus, and Pratylenchus ventroprojectus) are described from Adak Island in the Aleutian chain. M. adakensis n. sp. is separated from other species by body length (0.96-1.3 mm), stylet length (32-36 [mu]m), number of tail annules (49-68), and c' (3.1-4.1). P. megalobatus n. sp. differs from all known Pratylenchoides spp. by having a very long esophageal gland lobe (b' = 2.4-3.3, overlap 3-6 times the body width). P. pratensisobrinus n. sp. closely resembles P. pratensis (de Man) Filipjev, but has a longer stylet (15-17 [mu]m), a longer tail (c = 12-15; c' = 2.8-3.7), and more tail annules (23-37). P. ventroprojectus n. sp. is distinguished by body length (392-475 [mu]m), three lip annules, low and flattened cephalic capsule, and presence of terminal subventral projection. Pratylenchoides variabilis Sher, Helicotylenchus amplius Anderson & Eveleigh, and H. spitsbergensis Loof are also reported from Adak and Amchitka Islands. Key words: stunt nematodes, root-lesion nematodes, spiral nematodes, taxonomy, ectoparasites, endoparasites, new species.