Variation and diversity of symbiotic protist composition in the damp-wood termite Hodotermopsis sjoestedti

Abstract

SUMMARY It is well recognized that composition of termite symbiotic protist community generally show hostspecies specificity at species-to-species level. On the other hand, studies focused on population or colony level variations of the protist composition are few, although such studies are necessary for understanding the termite-protist mutualism. In this study we investigated symbiotic protist fauna of 34 Hodotermopsis sjoestedti nests collected from five islands in the Ryukyu Archipelago, Taiwan Is., and southern part of Chinese continent. Thirteen parabasalid species and six oxymonad species, which were reported from the host termite collected in Yakushima Is., were recognized in this study. Four parabasalids were identified as recently described species from H. sjoestedti collected in Vietnam. The fauna was the most speciesrich among the termite hosts studied to date, possibly reflecting large host body size. The prevalence rates of the symbiotic protist species are generally high, 100% in all populations for all protist species, except Gen. A sp. and Hoplonympha sp. All host nests had identical protist species composition except for the presence or absence of Gen. A sp. Two host populations lacked this species. In Yakushima Is., both types of termite nests were found, which exhibited mutually exclusive distribution. The distribution pattern suggests that the host termite is a multiple-site nester and nest-budding occurs in the field.