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411.
412.
S.R. Telford 《International journal for parasitology》1982,12(1):17-22
Telford S. R., jr. 1982. Interpopulation variation of a saurian malaria. Plasmodium sasai Telford & Ball, 1969, in three host species distributed within a range of 24° north latitude. International Journal for Parasitology12: 17–22. The saurian parasite P. sasai has been found in four populations of three host species which range from Niigata Prefecture, Honshu to Bangkok, Thailand, a distance exceeding 4600 km and 24° north latitude. Variation of P. sasai within samples from the type population exceeds that found among samples from all three hosts, Takydromus tachydromoides (Honshu), T. smaragdinus (Amami Island, Ryukyus) and T. sexlineatus (Thailand). Plasmodium sasai was associated with Trypanosoma sp., Schellackia sp. and Pirhemocyton in two or more host species in ricefield-margin habitat bordered by shrub-like or heavier vegetation. This association possibly represents persistence of a host-parasite complex which evolved with an ancestral lacertid stock that later diversified into the present Takydromus species. 相似文献
413.
Millipedes tend to have a near random dispersion pattern when surface active. Only in a few species do juvenile stadia form dense swarms. This study describes the occurrence and composition of aggregations in an adult population of the tropical spirostreptid millipede Alloporus uncinatus (Attems) inhabiting riparian forest in Zimbabwe. Also presented are the results of a field experiment designed to induce aggregation behaviour in a separate population with the addition of high quality food to the habitat.
Our initial hypothesis that the natural aggregations of between six and 42 individuals observed during the period of surface activity were part of the mating system in this species was refuted. Few mature males were present in aggregates and less than 1%, of copula pairs sampled were taken from aggregates. The composition of aggregates and the results of the experiment suggest that aggregations are associated with the feeding activities of immature individuals and are not related to reproductive activity. We suggest that the aggregations observed in A. uncinatus , although related, may perform different functions to the swarming behaviours observed in other millipede species. 相似文献
Our initial hypothesis that the natural aggregations of between six and 42 individuals observed during the period of surface activity were part of the mating system in this species was refuted. Few mature males were present in aggregates and less than 1%, of copula pairs sampled were taken from aggregates. The composition of aggregates and the results of the experiment suggest that aggregations are associated with the feeding activities of immature individuals and are not related to reproductive activity. We suggest that the aggregations observed in A. uncinatus , although related, may perform different functions to the swarming behaviours observed in other millipede species. 相似文献
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