摘要
于1991年4,5月在山东潍坊一对虾育苗池中发现一小型盾纤目纤毛虫,经鉴定确定为一新种——双核平腹虫Homalogastra binucleata nov. sp.。借助各银染法及生物统计学方法对其分类及形态学特征作了描述。新种的特点为:体呈倒梨形;胞口位于体后半部;约16列体纤毛,其第n列贯穿尾极后交于背方第8,9列纤毛间;具独特的两个大核。鉴于该属系国内首次报道,同时由于迄今对本属描述所存在的混乱,文中另对平腹虫属的定义、系统地位及与相近种属的关系做了补充和探讨,将其同物异名圆尾虫属(Urocyclon)并入本属并由此建立起两个新组合Homalogastra filificum nov. comb., H. chesapeakensis nov. comb.。
The morphology, infraciliature and silver line system of a new marine scuticociliati, Homalogastra binucleata nov. sp. from Weifang, Shandong Province, China in April and May, 1991, are described.Diagnosis of new species: Small to medium size, pear-shaped marine Homa-logastra in vivo ca. 25-35 μm×12-20 μm, with 2 macronuclear segments; contractile vacuole opening at the end of the 2nd kinety, caudal cilium often connected with a thread of mucus, with which the animals attach themselves to detritus; ca. 16 somatic kinetics; direct as well as check-like indirect silverline system typical of the genus, the basal-body-complex opens into the posterior circular fibril between meridians 8 and 9.Remarks: As compared with its closely related species, H. filificum (KAHL, 1931) nov. comb., the new species is characterized by the following peculiarities: 1) it always has two macronuclear segments, and 2) the location of the last meridional silverline (SKn) at the posterior end, which passes across the caudal pole and joins the circular fibril between kineties 8 and 9 but not between 11 and 12 (Fig. 4).Type specmens: One slide of holotype specimens and 4 slides of paratype speci-mens are deposited in the Laboratory of Protozoology, College of Fisheries, Ocean University of Qingdao.Behaviour and ecology: In fresh collections and in cultures the animals tend to swim near the bottom of the dish and are, occasionally, suspended in great abundance in the) water. On the bottom animals are often connected by a fine thread (through the caudal cilium) with the detritus and like that of H. filificum, revolving about the point of attachment. The species was collected from a marine shrimp farming pond in Weifang on the Bohai coast. Ecological characters: salinity about 24, pH 7.8-8.0, water temperature 19-22℃.By lack of feature 'rear left 1/4 of body unciliated', the genus Urocyclon Small & Lynn, 1985 should be considered as a junior synonym of Homalogastra, Hence, two new combinations can be established: H. filificum (formerly Uroc
出处
《海洋与湖沼》
CAS
CSCD
北大核心
1993年第2期143-150,共8页
Oceanologia Et Limnologia Sinica
基金
国家自然科学基金
39000011号
关键词
海洋
纤毛虫
盾纤目
双核平腹虫
Marine ciliate Scuticoclliatida Homalogastra binucleata
