摘要
本文描述了田螺科Viviparidae一新种——滇池圆田螺Cipangopaludina dianchiensis。模式标本采自滇池西南部的白鱼口湖区。本种贝壳大,最大个体壳高25.4mm、宽50.2mm。壳顶尖,有7个螺层,除顶部螺层外,各螺层中部均外凸呈角状,上部具宽阔的阶区。体螺层具7—12条螺棱。相似种长螺旋圆田螺Cipangopaludina longispira(Heude)各螺层中部均不外凸呈角状,上部亦不具阶区,且体螺层只有5条不大清楚的螺棱,两者有明显的区别。齿舌公式:3—4(1)3—4·4(1)4·4(1)4·11—13。幼体4个螺层,壳顶尖,第3和第4螺层上具2—4条螺棱,其上列生角质毛。本种分布仅局限于滇池西南隅。根据湖泊演变状况和湖内田螺科其他属种现行的分布格局推测,它可能是属于分布范围缩减和种群趋衰的种。
In this paper a new species of genus Cipangopaludina belonging to Viviparidae is described.Cipangopaludina dianchiensis sp. nov. (figs. 1-5)Localities: Bai-yu-kou, Guan-yin hill and Kunyang bay in Dianchi lake (N24°50' E102° 40').Shell pyramid, large, thick and solid. whorl 7. Except the apex, each spiral whorl with canvex part as angle in media] part and broad plane in upper part. Breadth of each spiral whorl increases rapidly. Apex acute, suture deep. The surface of shell grey brown with thick grown-line. Body whorl expanded with 7-12 smooth and slender transversal ribs. Aperture oval shaped, outer lip round. Inner lip turned out and upper part covered on body whorl. Operculum red brown, pear shape. Umbilicus covered by inner lip.Radular consists of about 100 ranks tongue teeth. Several ranks of front part red brown and the rest enveloped in a muscle sheath, yellow or colurless.Formular 3-4(1)3-4'4(1)4-4(1)4-11-13.Juvenile (figs. 4-5): Whorl 4, apex acute, third and forth whorl with 2-4 ribsr horny hair arranged on them.Holotype (YD-33095): length 75.4mm, breadth 50.2mm, length of aperture 35.3mm.Paratypes; length 65.7-66.9mm, breadth 45.6-49.7mm, length of aperture 30.8-32.4) mm.All type specimens collected from Dianchl Lake in Yunnan Province, are deposited in Nanjing Institute of Geography.
出处
《动物分类学报》
CSCD
1990年第1期25-27,共3页
Acta Zootaxonomica Sinica
关键词
中腹足目
田螺科
圆田螺属
新种
Mesogastropoda Viviparidae Cipangopatudina new species.
