Cestode fauna of Columbiformes in Vietnam.
Eleven species of cestodes, including 4 new species of Raillietina, were found on examination of 258 Columbiformes belonging to 6 species (Streptopelia chinensis, S. orientalis, S. tranquebarica, Treron curvirostra, Sphenurus sieboldii and Chalcophaps indica) from 14 provinces of Vietnam. R. joyeuxbaeri n.sp. from one of 17 Streptopelia tranquebarica is characterized by the size of the strobila (20 to 30 mm long, 0.26 mm wide) with numerous rounded proglottides and an offset spherical scolex, and by having about 250 rostellar hooks 0.011 to 0.013 mm in length and 6 to 7 testes. Although 30 young and mature strobilae were found, none contained gravid proglottides. R. macrorhyncha n.sp. from 3 of 33 T. curvirostra is similar to R. ortleppi, R. idiogenoides, R. columbiella and R. spiralis in having a small strobila (20 to 30 mm long), similar scolex, a large cirrus pouch and a muscular armed cirrus, but differs principally by the relative measurements of the scolex, which when invaginated is 3.5 to 4 times the diameter of the suckers, and in the size of the rostellar hooks which are 18 to 22 mm in the first row and 22 to 26 mm in the 2nd row. R. microrhyncha n.sp. from 2 of 167 S. chinensis, having a round scolex with a relatively small rostellum armed with 100 to 160 hooks reaching 8-9 mu m in length and a small cirrus pouch, is close to species of Raillietina from galliform birds, particularly R. tetragona, and to R. cohni but is distinguished from these in possessing an internal seminal vesicle and in other characters. R. vietnamense n.sp., 2 specimens of which were found in one of 8 S. chinensis, is near to R. tetragona and R. microrhyncha in having a small rostellum and large oval suckers. However, the scolex and its parts are smaller in the 2 new species than in R. tetragona from domestic fowl in Vietnam, the spined zone on the suckers narrows from the front to the back edge and the rostellar hooks are fewer and in 2 rows. R. vietnamense differs from the other 2 species by a considerably shorter and wider strobila (90 to 100 x 4.5 to 5.0 mm) and approximately 300 parenchymatous capsules, each containing 1 or 2 eggs but not more than 4. R. carpophagi from T. curvirostra shows some differences from earlier descriptions from other hosts: the rostellum and hooks are somewhat smaller, the cirrus pouch narrower and there are 35 to 50 capsules with 3 to 13 eggs/capsule. Brief illustrated descriptions are given of R. frayi based on 36 specimens collected from one of 5 Sphenurus sieboldii and of R. fuhrmanni collected from 2 of 33 T. curvirostra (for the first time in Vietnam). R. interrupta [n.comb.] is widely distributed in Vietnam, being found in 15% of Streptopelia chinensis and 12% of S. orientalis. In 1973, Spasski & Jurpalova described the new genus and species Skrjabinotaurus interruptus, from Streptopelia chinensis, which is morphologically identical with the new material. The present authors consider the new genus to be unjustified and synonymise it with Raillietina. They discuss variations in the distribution of sucker spination within Raillietina, pointing to the existence of 2 morphologically distinct groups, one containing most of the species of the genus, the other the new species R. microrhyncha and R. vietnamense. The 3 other species reported are Aporina delafondi, Cotugnia meggitti and Sphenacanthus serrata.