Review of Chinese Oligaphorurini (Collembola, Onychiuridae) with descriptions of two new Palaearctic species

Abstract A checklist of Chinese Oligaphorurini is given. Two new Chinese species, Micraphorura changbaiensis sp. n. and Oligaphorura pseudomontana sp. n., are described from Changbai Mountain Range. Micraphorura changbaiensis sp. n. has the same dorsal pseudocelli formula and number of papillae in Ant. III sensory organ as Micraphorura uralica, but they can be easily distinguished by number of chaetae in Ant. III sensory organ, ventral pseudocelli formula, ventral parapseudocelli formula, number of pseudocelli on subcoxa 1 of legs I–III, dorsal axial chaeta on Abd. V and number of chaetae on tibiotarsi. Oligaphorura pseudomontana sp. n. is very similar to the species Oligaphorura montana having an increased number of pseudocelli on body dorsally, well marked base of antenna with 1 pseudocellus and 3 pseudocelli outside, subcoxa 1 of legs I–III with 1 pseudocellus each, dorsally S-chaetae formula as 11/011/22211 from head to Abd. V, S-microchaeta present on Th. II–III, claw without inner teeth and with 1+1 lateral teeth, and unguiculus with basal lamella; but they can be separated easily by the number of pseudocelli on Abd. V and VI terga, parapseudocelli on the body, number of chaetae on Th. I tergum, and number of chaetae on tibiotarsi. A key to Chinese species of Oligaphorurini is provided in the present paper.


introduction
The tribe Oligaphorurini, erected by Bagnall (1949) as a subfamily, is characterized by having a small postantennal organ with a 3-5 lobed vesicle. So far, 38 species belonging to five genera were reported in the world (Bellinger et al. 2012). Nevertheless, the Chinese fauna of Oligaphorurini is poorly known, only two species, Dimorphaphorura sanjiangensis Sun & Wu, 2012 and Oligaphorura ursi (Fjellberg, 1984), were reported from northeast China (Sun and Wu 2012).
In the present paper, two new Chinese Oligaphorurini species are described from Changbai Mountain Range in Jilin Province, and two newly recorded species, Oligaphorura judithae (Weiner, 1994) and Oligaphorura koreana (Weiner, 1994), are mentioned. A checklist of Chinese Oligaphorurini and an identification key to all Chinese species of this tribe are given below.

Material and methods
Specimens were mounted in Marc André II solution, after clearing in lactic acid, and were studied using a Nikon Eclipse 80i microscope. Material is deposited in the Key laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun.
S-chaetae formula is the number of S-chaetae by half tergum from head to Abd. VI (for instance: 11/011/222111).
Etymology. Named after the mountain range where we found the new species. Ecology. Found in coniferous forest.
Etymology. Named for the similarity with the Korean species O. montana Weiner, 1994. Ecology. Found in coniferous forest.
Remarks. The new species is very similar to the species montana collected in the mountain of North Korea, sharing the following characters: an increased number of pseudocelli dorsally; well marked base of antenna with 1 pseudocellus and 3 dorsal pseudocelli outside; subcoxa 1 of legs I-III with 1 pseudocellus each; dorsally S-chaetae formula as 11/011/22211 from head to Abd. V; S-microchaetae present on Th. II-III; head with chaeta p1 level with p2; Th. I, II and III sterna without chaetae; anal spines 0.75 times as long as inner edge of unguis; claw without inner teeth but with one lateral tooth; unguiculus with basal lamella. But they can be separated easily by the number of pseudocelli on Abd. V and VI terga (5 and 3 in montana versus 6 and 4 in pseudomontana sp. n.), parapseudocelli on the body (indistinct in montana, versus 00/000/222401 by half-sternite in pseudomontana sp. n.), the number of chaetae on Th. I tergum (7+7 in montana versus 6+6 in pseudomontana sp. n.), and the number of chaetae on tibiotarsi (19, 19, 18 in montana versus 20, 20, 19 in pseudomontana sp. n.).