斯氏并殖吸虫第一中间宿主拟钉螺属一新种记述(中腹足目,盖螺科)

A new species of Tricula as the first intermetiate host of Paragonimus skriabini(Mesogastropoda: Pomatiopsidae) from China

为调查斯氏并殖吸虫拟钉螺宿主,现场采集螺标本,进行形态分类和生态考察及螺体寄生虫检查。发现拟钉螺属(Tricula)一新种,命名为建欧拟钉螺(Tricula jianouensissp.nov.),螺壳高3.125 mm,壳宽1.600 mm,体螺层高1.125 mm,壳口长径1.275 mm,壳口宽径0.925 mm。螺口外缘翘起呈铲状;轴缘与外缘形成较窄夹角,内唇嵴明显高出,与体螺层间有一沟状隙。齿舌每一横列有7枚齿,齿式:2-1-2/2-2.3-1-3.11(14).14(15)。该螺充当斯氏并殖吸虫第一中间宿主,斯氏并殖吸虫尾蚴感染率为0.11%。

During the Nov. 2006, lots of minute freshwater snails were collected from Jian＇ou City, Fujian Province, China, and among the collections, a new species of Tricula （Mesogastropoda. Pomatiopsidae） was identified. Based on morphology of the shell and radula, a new specie T. jianouensis sp. nov. was described, and the diagnosis features of the new species and the similar species T. fujianensis were also given. All the type specimens are deposited in Fujian Municipal Center for Disease Control and Prevention.Tricula jianouensis sp. nov. Shells are minute, thick, opaque, size ranging in height from 1.54-1.64 mm. They are broad conicshaped with 5 whorls. Whorls increase rapidly in height with a ladder-liked, penultimate whorl and apical whorl are often absent. Shell height is 2.78 times of body whorl, apex obtuse, shell surface smooth with light green-yellow color. Body whorl is little expended and has weak growth lines on shell surface. Suture is shallow. Columellar fold and outer lip form a narrow angle, outer lip of aperture shovel liked, pronounced varix on inner lip, and form a gouge-liked gap. Operculum is elongate ellips, corneous thin and transparent, with unconspicuous spiral line. The penis is curved finger-shaped, lies on the dorsa of neck. Radula has seven rows of teeth. The most commonly encountered cusp formula is 2-1-2/2-2 ·-3-1-3· 11（14） ·14（15）. Central teeth have 5 cusps and two pieces of basocones on each side of the base, and the middle cusps are obviously longer. Later teeth have 7 cusps. The inner marginal teeth average 11-14 cusps, while outer marginal teeth clearly have fewer, an average of 14-15. Locality and habitat. Type locality of the new species is in Qiliken village, xiaoqiao town, Jianou city, Fujian province, 26 08° 07＂ N,117° 40′ 12＂ E. Snails were collected from a small ditch with slow water flow- ing and rock, dead wood on the bottom. Snails attach on the rock, dead wood and leaves. The diagnosis features of new species and similar species were given in table 1.