双冠属线虫一新种(圆形目:盅口科)

A NEW SPECIES OF CYLICODONTOPHORUS (STRONGYLIDEA: CYATHOSTOMIDAE)

本文记述从中卫县马属动物大肠中检获的双冠属线虫一新种,命名为中卫双冠线虫(Cylicodontophorus zhongweiensis sp.nov.),对新种的形态特征作了详细描述,并与近似种麦氏双冠线虫C.mettami进行了对比。

In 1982—1983, we surveyed parasitic helminthes of the domestic equine animals of Zhongwei County (37°N, 105°E), Ningxia Hui Autonomous Region, China. A species of nematode was collected from the large intestine of domestic horses, donkeys and mules, and by careful examination, it was found different from the others member of the genus Cylicodontophorus and nominated as a new species.Cylicodontophorus zhongweiensis sp. nov. (figs. 1—7)Body filiform, medium sized. Mouth collar conspicuous, anterior margin flat and straight, 0.0272—0.0340mm in altitude. Buccal capsule circumference having two around leafcrowns. The internal leafcrown composed of 42—46 big long pointed elements that originate in identical level, slightly under the anterior margin of buccal capsule; the external leafcrowu composed of 62—68 very small and pointed elements. They are about 1:1.5 in proportion. Head with 4 submedian papillae and 2 amphids. Buccal capsule shallow and wide, the width is bigger than the depth, with 3:1 in proportion; the thickness of wall is approximately unanimous; the bottom surrounded by spot-like projections. No dorsal gutter, Oesophageal funnel big with three small teeth in it.Male Body 9.0—10.7mm in length and 0.462—0.588mm in width. Bursa consisting of 3 lobes, the dorsal lobe obvious. External dorsal ray arising from the base of the dorsal. Dorsal ray cleft, each branch giving off two laterals, Spicules one pair, equal in size and similar in shape, 2.100—2.394mm in length and 0.0210--0.0238mm in width, hook-shaped at the posterior extremity. Genital cone well-developed, projecting over the copulatory bursa margin, 0,630—0.816mm in length, the dorsal lip shorter and wider than ventral lip, with two spines situated at the surface of posterior, 0.112—0.140mm from posterior end, spine 0.0272—0.0510mm in length, with spinelet on them.Female Body 13.0—16.5mm in length and 0.847—0.980mm in width. Vulva 0.385—0.560mm to the caudal end. Vagina 0.210—0.826mm in length. Tail 0.259—0.392mm in length and digitiform. Eggs in uterine extremity, long-elliptical, 0.112—0.168mm in length and 0.056—0.070mm in width.Host Equus caballus, Equus asinus and Equus caballus x Equus asinus.Location Large intestine.Locality Zhongwei County (37°N, 105°E), Ningxia Hui Autonomous Region, China.Types Holotype (?), allotype ♀, paratype (?), 9♀♀, deposited in Zhongwei Animal Quarantine Station, Ningxia, China.The ratio of the number of internal and external leafcrown of new species is 1:1.5, different from the other member of the genus Cylicodontophorus. But it resembles Cylicodontophorus mettami, and differs from, the latter in having the ratio of width to depth of buccal capsule 3:1, bottom deeper in ventral than in dorsal, surrounded by spot-like projections; The latter having the ratio of width to depth 2.6:1, bottom smooth. The new species having oesophageal funnel with three small teeth; the latter without; spicules(2.100—2.394mm) longer than the latter (1.950mm); genital cone accessory spinosesform with spinelet on them; the latter bubbleform.