To assess the accuracy of species delimitation in the genus Aphaenomurus Yosii, we conducted a comparative micro-morphological study and molecular analysis using two mitochondrial (COI, 16S) and two nuclear genes (18S, 28S) on 118 specimens from 24 localities. The results showed that the morphological characters of A. vicinus and A. interpositus, as presented in the original description, were intermixed in phylogenetic lineages within the genus and did not form independent lineages. Furthermore, there were enough differences among Aphaenomurus individuals to be considered as morphologically distinct species (Th. III is 1+1 or 2+2, Abd. I is 2+2 or 3+3, Abd. II is 2+2 or 3+3), but they do not form an independent lineage. Molecular and morphological analyses have determined that A. vicinus and A. interpositus are the same species, exhibiting morphological variation in dental spines formula, claws, chaetotaxy, and other features. Additionally, the genus Aphaenomurus forms a monophyletic clade, which is further divided into several lineages within the genus. No morphological differences were observed to distinguish these lineages. This cladistic divergence is attributed to heteroplasmy, which is supported by previous studies that have suggested the possibility and problems of heteroplasmy in Collembola, and by the high genetic distances between individuals in the mitochondrial genes of Aphaenomurus.
A new species of the cave-dwelling springtail Lethemurus coreanus Chang and Bae, sp. n. is described from Korea. Lethemurus coreanus can be distinguished from congeners by the spinelike setae on the tibiotarsus, numbers of dental spines, number of setae on the trochanteral organ, and body macrochaetae chaetotaxy. A key to the species of Lethemurus is provided.
Cave-dwelling springtail studies in Korea initiated during 1960s by the Japanese Collembola researcher, R. Yosii, and comprehensive taxonomic studies on Korean Collembola were conducted by B. H. Lee during 1970-1990s wherein the new family Gulgastruridae was established using the type species Gulgastrura reticulosa from the Gossidonggul cave in Gangwon-do, South Korea. Eight families of cave-dwelling Collembola are known in Korea, and the family Tomoceridae is the most abundant and diverse group of cave-dwelling Collembola with 11 known species belonging to 4 genera in Korea. In this study, 12 species of Korean Tomoceridae are reviewed, and 1 new species from the genus Plutomurus and 2 new species from the genus Tomocerus are described.