Gong Jun, Song Weibo, Li Lifang, Shao Chen, Chen Zigui
Laboratory of Protozoology, Ocean University of China, Qingdao, PR China.
Eur J Protistol. 2006 Mar;42(1):63-73. doi: 10.1016/j.ejop.2005.12.001. Epub 2006 Feb 3.
The morphology and infraciliature of the type species of the ciliate genus Trachelostyla, T. pediculiformis (Cohn, 1866) Borror, 1972, collected from the Bohai Sea near Tianjin, north China, were investigated using live observation and protargol impregnation. The Chinese population corresponds well with the original description, as follows: size about 80-150 x 20-30 microm in vivo; body dorsoventrally flattened and non-spiral; outline elongate, with anterior region conspicuously narrowed while posterior not; on average 14 macronuclear nodules, two micronuclei and 42 adoral membranelles; 16-24 cirri in left and 21-31 in right marginal row. In total 18 frontoventral-transverse cirri: constantly 11 cirri in frontal area and two ventral ones together with five enlarged transverse cirri (TC). Three inconspicuous caudal cirri (CC); six dorsal kineties with prominent cilia. The literature on T. pediculiformis is critically reviewed, showing that the descriptions so far do not agree very well. To clarify the taxonomic status of this species, the population from the Chinese coast of the Bohai Sea is designated as a neotype. The small subunit rRNA gene was sequenced for the neotype and the molecular phylogenetic tree basically supports the establishment of the family Trachelostylidae Small & Lynn, 1985. Based on the data obtained, the genus Trachelostyla Borror, 1972 is redefined thus: dorsoventrally flattened trachelostylids, body non-spirally twisted and elongate, with peristomal region conspicuously narrowed; ciliature generally in 11:2:5:3 pattern, i.e. 11 cirri in frontal region, two ventral cirri located anterior to five TC, three CC present; one left and one right row of marginal cirri not confluent posteriorly. A new genus Spirotrachelostyla nov. gen. is proposed to include the taxa which were previously assigned to Trachelostyla but characterized by spirally twisted, spindle-like body shape and a variable number of cirri in the peristomal area. Three new combinations are suggested: Spirotrachelostyla spiralis (Dragesco & Dragesco-Kernéis, 1986) nov. comb. [basionym: Trachelostyla spiralis Dragesco & Dragesco-Kernéis, 1986], S. tani (Hu & Song, 2002) nov. comb. [basionym: T. tani Hu & Song, 2002] and S. simplex (Kahl, 1932) nov. comb. [basionym: Stichotricha simplex Kahl, 1932].
利用活体观察和蛋白银染色法，对采自中国北方天津附近渤海海域的纤毛虫类柱颈虫属（Trachelostyla）的模式种——纤颈柱颈虫（Trachelostyla pediculiformis (Cohn, 1866) Borror, 1972）的形态和纤毛下器进行了研究。中国种群与原始描述非常相符，具体如下：活体大小约80 - 150×20 - 30微米；身体背腹扁平且不呈螺旋状；轮廓细长，前部明显变窄而后部不变窄；平均有14个大核结节、两个小核和42个口围小膜；左缘纤毛列有16 - 24根纤毛，右缘纤毛列有21 - 31根纤毛。共有18根额腹横纤毛：额区始终有11根纤毛，两根腹纤毛以及五根增大了的横纤毛（TC）。三根不明显的尾纤毛（CC）；有六列背纤毛，纤毛显著。对有关纤颈柱颈虫的文献进行了批判性综述，结果表明目前的描述并不十分一致。为了阐明该物种的分类地位，将来自中国渤海海岸的种群指定为新模标本。对新模标本的小亚基rRNA基因进行了测序，分子系统发育树基本支持了1985年Small和Lynn建立的柱颈虫科（Trachelostylidae）。根据所获得的数据，对1972年的柱颈虫属（Trachelostyla Borror）重新进行了定义：背腹扁平的柱颈虫类，身体不呈螺旋状扭曲且细长，口区明显变窄；纤毛下器通常呈11:2:5:3模式，即额区有11根纤毛，两根腹纤毛位于五根TC之前，有三根CC；左、右缘纤毛列在后部不汇合。提出了一个新属——螺旋柱颈虫属（Spirotrachelostyla nov. gen.），以包括那些以前被归入柱颈虫属但具有螺旋状扭曲、纺锤形身体形状且口区纤毛数量可变特征的类群。提出了三个新组合：螺旋螺旋柱颈虫（Spirotrachelostyla spiralis (Dragesco & Dragesco-Kernéis, 1986) nov. comb.）[基原异名：柱颈虫属螺旋柱颈虫（Trachelostyla spiralis Dragesco & Dragesco-Kernéis, 1986）]、谷氏螺旋柱颈虫（S. tani (Hu & Song, 2002) nov. comb.）[基原异名：柱颈虫属谷氏柱颈虫（T. tani Hu & Song, 2002）]和简单螺旋柱颈虫（S. simplex (Kahl, 1932) nov. comb.）[基原异名：单缝毛虫属简单单缝毛虫（Stichotricha simplex Kahl, 1932）]。
