Notes on Metaphire multitheca (Chen, 1938) (Oligochaeta, Megascolecidae) recorded from Vietnam, with descriptions of two new species

Abstract. The paper deals with Pheretima multitheca multitheca Chen, 1938 recorded from Vietnam (non Pheretima multitheca Chen, 1938 now in Metaphire from Hainan Island). As a result, a new species, Amynthas erroneous sp. n., is revealed from materials which were previously misidentified as Pheretima multitheca multitheca. The new species is obviously distinguished from other Amynthas species by multiple spermathecal pores lateroventral in intersegments 5/6/7/8/9, and presence of two pairs of crescentic genital markings in xviii. In addition, another new species, Amynthas nhonmontis sp. n., is described and easily recognized by multiple spermathecal pores ventral in intersegments 5/6/7/8 and three pairs of genital markings in xvii, xix and xx.