海水鱼类单殖吸虫鳞盘虫属一新种描述(指环虫目,鳞盘虫科)

ON THE MONOGENEA OF CHINESE MARINE FISHES ONE NEW SPECIES OF THE GENUS DIPLECTANUM DIESING (DACTYLOGYRIDEA,DIPLECTANIDAE)

报告采自长尾大眼鲷PriacanthustayenusRichardson上之鳞盘虫属 1新种 :粗管鳞盘虫Diplectanumrobusti tubumsp .nov.,它以交接器之结构、后吸器中央大钩及联结片形态之差异而区别于D .curvivaginaYamaguti,1968。

This paper reports a new species of genus Diplectanum Diesing, 1958, from Sanya in the South China Sea. Type specimens are deposited in the Department of Biology, South China Normal University. All measurements are in micrometers, the measurement adopted for hamuli refers to that of Oliver, 1968 and Gussev, 1955.Diplectanum robustitubum sp. nov. (图1～2) Host. Priacanth tayenus Richardson. Location. Gills. Locality. Sanya (18°18′N,109°27′E) Hainan Province;Huizhou,Guangdong Province. Description. Worms of medium size, body width 127(104-228), length 575(487-676). Haptor 94(91-130) × 180(169-197) in size. Pharynx suboval, diameter 43(39-47). Squamodiscs are composed of 10-11 concentric rows of rodlets. Marginal hooklets 9.2(8-10). Ventral hamuli with developed outer and inner roots, according to Gussev, 1955, the dimensions are: portion 32 (29-34), point 9 (8-10), total length 46 (42-49), inner root 17 (13-21), outer root 16(13-18); dorsal hamuli portion 29(26-36), point 7(4-8), total length 40(38-42), inner root 12(5-16), outer root 5(3-8). According to Oliver, the dimensions are: ventral hamuli, length a: 46(42-49), length b:45(39-49), length c: 30(20-48), length d:23(13-28), length g:16(13-21), length f: 16(13-18); dorsal hamuli, length a: 40(39-42), length b: 32(23-38), length c: 19(18-21). Median connective plate is arc-like,7(5-8)×73(65-75). Transverse connective plate 10(8-10)×72(65-78) in size, with some spine-like protusions at lower part of inner side. Male copulatory organ C-shaped, consists of copulatory tube and supporting apparatus, length of tube 42(34-46). Its middle part thicker than two ends. The copulatory tube with a bell base crosses the supporting apparatus, which is curve-shaped with the length of 38(31-44) and the middle part middle part thicker and two ends thinner. Vaginal tube and egg were not found. Description is based on 9 specimens. Remarks. The new species is similar to D. curvivagina Yamaguti, 1968, but is well distinguished from the latter in the following structures: the male copulatory organ is shorter and has obvious supporting apparatus; the two ends of male copulatory organ are thinner; the diamete of the sqaumodisc is larger than the length of ventral hamuli; there are little spines in the lower part of inner side of transverse connective plate. What's more,the new species also smaller in it size.