Simões S B E, Barbosa H S, Santos C P
Laboratório de Avaliação e Promoção da Saúde Ambiental, Departamento de Biologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Rio de Janeiro 21040-900, Brazil.
J Parasitol. 2005 Aug;91(4):931-6. doi: 10.1645/GE-417R.1.
Pygidiopsis macrostomum Travassos, 1928, a poorly known species originally described from a single specimen from Rattus norvegicus (Erxleben, 1777) in Brazil, is redescribed on the basis of metacercariae from the mesenteries of naturally infected guppies Poecilia vivipara Bloch and Schneider, 1801 (Poeciliidae), and adults obtained from an experimental infection of hamsters. Pygidiopsis macrostomum is characterized by the absence of oral spines, vitellaria extending forward to ventral sucker, uterus reaching pharyngeal level, X-shaped excretory vesicle, and an oral sucker/acetabulum ratio of 1:0.8. The surface ultrastructure shows that the tegument of the metacercaria does not strongly differ from that of adults. The brush-shaped spines of P. macrostomum are similar to those reported for Pygidiopsis summa and Pygidiopsis ardeae, but no differences in spine shape were observed throughout the body.
大口矮体吸虫（Pygidiopsis macrostomum Travassos，1928）是一种鲜为人知的物种，最初是根据采自巴西褐家鼠（Rattus norvegicus，Erxleben，1777）的单个标本描述的。本文根据自然感染的孔雀花鳉（Poecilia vivipara Bloch和Schneider，1801，花鳉科）肠系膜中的后尾蚴以及通过仓鼠实验感染获得的成虫，对大口矮体吸虫进行了重新描述。大口矮体吸虫的特征为无口棘，卵黄腺向前延伸至腹吸盘，子宫到达咽部水平，排泄囊呈X形，口吸盘与腹吸盘的比例为1:0.8。表面超微结构显示，后尾蚴的体表与成虫的体表没有明显差异。大口矮体吸虫的刷状棘与报道的苏氏矮体吸虫和鹭矮体吸虫的棘相似，但在虫体全身未观察到棘的形状差异。
