Justine Jean-Lou, Euzet Louis
Equipe Biogéographie Marine Tropicale, Unité Systématique, Adaptation, Evolution (CNRS, UPMC, MNHN, IRD), Institut de Recherche pour le Développement, BP, A5, 98848 Nouméa Cedex, Nouvelle Calédonie.
Syst Parasitol. 2006 Jul;64(3):147-72. doi: 10.1007/s11230-006-9028-8. Epub 2006 May 5.
Echinoplectanum n. g. is erected for diplectanids which have a male copulatory organ comprising a tubular sclerotised penis with a muscular reservoir at its proximal extremity and an protrusible cirrus, often with spiny ridges, at its distal extremity, and a female copulatory organ comprising a sclerotised vaginal sac, often with two thin tubes. All species have similar squamodiscs made of rows of rodlets, with the central rows forming closed circles, and haptoral parts with a similar shape but different measurements; they are distinguished on the basis of the size and morphology of the male copulatory organ and sclerotised vagina. Five new species are included in Echinoplectanum and are all parasites of coralgroupers, Plectropomus spp., off New Caledonia, South Pacific. Two are from P. laevis (Lacépède): E. laeve n. sp. (type-species) has a large elongate penis, 53[Formula: see text]m in length, a cirrus with spiny ridges and a spherical vagina with two long thin tubes; and E. chauvetorum n. sp. has a large elongate penis, 51[Formula: see text]m in length, a cirrus with thin spiny ridges, and a pear-shaped vagina with two short thin tubes. Three species are from P. leopardus (Lacépède): E. leopardi n. sp. has an elongate penis, 36[Formula: see text]m in length, an unspiny cirrus and a triangular vagina; E. pudicum n. sp. has a very small elongate penis 14[Formula: see text]m in length and no visible vagina; and E. rarum n. sp. has a short thick penis 18[Formula: see text]m in length and a ring-shaped vagina with two thin tubes. In addition, Diplectanum plectropomi Young, 1969, from P. maculatus off Western Australia, and D. echinophallus Euzet & Oliver, 1965 from Epinephelus marginatus in the Mediterranean Sea and Senegal, West Africa, both herein redescribed from the type-specimens, are transferred to Echinoplectanum, as E. plectropomi n. comb. and E. echinophallus n. comb., respectively. Six of the seven species of Echinoplectanum are parasitic in members of Plectropomus from the South West Pacific, but one (E. echinophallus) is a parasite of Epinephelus marginatus and has been recorded only from the Mediterranean and East Atlantic; it is suggested that Echinoplectanum is associated with Plectropomus, a basal genus among the epinephelines, and that host-switching to Epinephelus marginatus occurred, whose distribution extends from Europe to the Indian Ocean. Morphological characteristics of the copulatory organs suggest that a "chastity belt versus spiny penis" sperm competition pattern prevails in Echinoplectanum spp.
新建立的棘盘虫属（Echinoplectanum n. g.）是指那些具有以下特征的双身虫类：雄性交配器官包括一个管状硬化阴茎，其近端有一个肌肉质贮精囊，远端有一个可伸出的阴茎，通常带有刺状脊；雌性交配器官包括一个硬化的阴道囊，通常有两根细管。所有物种都有由成排小杆组成的类似鳞片盘，中央排形成封闭的圆圈，以及形状相似但尺寸不同的吸器部分；它们根据雄性交配器官和硬化阴道的大小和形态来区分。棘盘虫属包括五个新物种，均为南太平洋新喀里多尼亚附近珊瑚石斑鱼（Plectropomus spp.）的寄生虫。其中两个来自光滑石斑鱼（P. laevis (Lacépède)）：新种光滑棘盘虫（E. laeve n. sp.）（模式种）有一个大型细长阴茎，长53[公式：见原文]微米，一个带有刺状脊的阴茎，以及一个带有两根长细管的球形阴道；新种肖韦棘盘虫（E. chauvetorum n. sp.）有一个大型细长阴茎，长51[公式：见原文]微米，一个带有细刺状脊的阴茎，以及一个带有两根短细管的梨形阴道。三个物种来自豹纹石斑鱼（P. leopardus (Lacépède)）：新种豹纹棘盘虫（E. leopardi n. sp.）有一个细长阴茎，长36[公式：见原文]微米，一个无刺的阴茎，以及一个三角形阴道；新种羞怯棘盘虫（E. pudicum n. sp.）有一个非常小的细长阴茎，长14[公式：见原文]微米，且无可见阴道；新种稀有棘盘虫（E. rarum n. sp.）有一个短粗阴茎，长18[公式：见原文]微米，以及一个带有两根细管的环形阴道。此外，1969年扬描述的来自西澳大利亚斑鳍石斑鱼（P. maculatus）的斑鳍双身虫（Diplectanum plectropomi Young），以及1965年厄泽和奥利弗描述的来自地中海和西非塞内加尔的边缘石斑鱼（Epinephelus marginatus）的具棘阴茎双身虫（D. echinophallus Euzet & Oliver），在此均根据模式标本重新描述，并分别转移到棘盘虫属，成为新组合种斑鳍棘盘虫（E. plectropomi n. comb.）和具棘阴茎棘盘虫（E. echinophallus n. comb.）。棘盘虫属的七个物种中有六个寄生于西南太平洋石斑鱼属成员，但一个（具棘阴茎棘盘虫）是边缘石斑鱼的寄生虫，仅在地中海和东大西洋有记录；有人认为棘盘虫属与石斑鱼属有关，石斑鱼属是石斑鱼科中的一个基部属，并且发生了宿主转换至边缘石斑鱼，其分布范围从欧洲延伸至印度洋。交配器官的形态特征表明，在棘盘虫属物种中存在一种“贞操带与带刺阴茎”的精子竞争模式。
