Spinitectus osorioi (Nematoda: Cystidicolidae) in the Mexican endemic fish Atherinella alvarezi (Atherinopsidae) from the Atlantic River drainage system in Chiapas, Southern Mexico

Memórias do Instituto Oswaldo Cruz

František Moravec²  Guillermo Salgado-maldonado¹  Juan M Caspeta-mandujano¹ 

[1] ,Biology Centre of the Academy of Sciences of the Czech Republic Institute of Parasitology eské Budejovice,Czech Republic

关键词: parasitic nematode;    Spinitectus;    freshwater fish;    Atherinella;    Chiapas;    Mexico;   

DOI  :  10.1590/S0074-02762010000100007

来源: SciELO

【 摘 要 】

Specimens of Spinitectus osorioi Choudhury and Pérez-Ponce de León, an intestinal nematode species previously considered to be specific to Chirostoma spp and endemic to some lakes in the Pacific drainage in Michoacán, were collected from the freshwater fish Atherinella alvarezi (Díaz-Pardo) (Atherinopsidae) of the Michol River near Palenque, Chiapas, Southern Mexico, which belongs to the Atlantic drainage system. Studies using light and scanning electron microscopy revealed some taxonomically important, previously unreported or erroneously reported features of S. osorioi, such as the location of the vulva, the actual number and distribution of postanal papillae and phasmids and the presence of a short median cuticular ridge anterior to the cloacal opening (in addition to two long subventral ridges). The recorded somewhat shorter spicules (420-465 and 105-111 μm) and mostly smaller eggs (33-36 × 18-20 μm) as compared to the original species description may be due to a different type of host, geographical region or generally smaller body measurements of these specimens. These biometrical differences are considered to be within the limits of the intraspecific variability of S. osorioi. A key to species of Spinitectus parasitizing freshwater fishes in Mexico is provided.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License