Two new free-living marine nematode species of the genus Anoplostoma (Anoplostomatidae) from the mangrove habitats of Xiamen Bay, East China Sea

Abstract

Two new species of free-living marine nematode from mangrove habitats in Xiamen Bay are identified. Anoplostoma tumidum sp. nov. is characterized by relatively short outer labial setae (0.86–1.00 h. d.), long tail (c 7.2–8.9, c’ 8.3–10.5), an instinct swollen distal portion of slender spicule (Sc 94–101 µm), and well developed copulatory bursae without bursal papillae. A. tumidum sp. nov. differs from all valid species of genus Anoplostoma in copulatory apparatus of males with a distinct swollen distal portion of spicule, and a relatively obvious constriction of head. A. paraviviparum sp. nov. is characterized by relatively long outer labial setae (1.11–1.22 h. d.), and tail (c 6.6–8.5, c’ 8.6–10.2); elongated spicules with distinct knob-like proximal and pointed distal ends (Sc 46–69 µm); distinct strip-like gubernaculum (length with 11–15µm); well developed copulatory bursae with precloacal papillae and post-cloacal papillae; and a distinct constriction of head. A. paraviviparum sp. nov. is similar to A. viviparum Bastian, 1865, but differs in the reproductive mode of female and the constriction of head.