A new species of Uralaphorura Martynova, 1978 from northeast China, with a key to world species of the genus (Collembola, Onychiuridae)

Abstract A new species, Uralaphorura liangshuiensis sp. n., has been reported from Xiao Hinggan Mountains (northeast China). The new species is unique in having the pso formulae as 32/133/33332 dorsally and 0/000/0001(0) ventrally, and the ventral psx formula as 3/000/221000. A key to all known species of the genus is given.


Introduction
established Uralia as a subgenus of Onychiurus Gervais, 1841 for O. schilovi Martynova, 1976. In 1978, she proposed a new name, Uralaphorura, instead of Uralia, as the former name has been used for a genus of birds. Later, Weiner (1996) raised the subgenus to generic level. The genus is characterized by having simple or slightly bilobed vesicles in PAO, chaeta d0 present on the head, eleven chaetae in the distal whorl of tibiotarsi, and a triangular arrangement of the anterior cephalic pseudocelli (Babenko 2009). To date, there are four known species belonging to the genus Uralaphorura: U. schilovi (Martynova, 1976) from northern Europe: U. varicellata Babenko, 2009, U. yanensis Babenko, andU. tunguzica Babenko, 2007 from Siberia. The latter was recently also recorded from China (Sun and Wu 2013).
Based on a study of specimens collected from Xiao Hinggan Mountains (northeast China), a new species is reported and a key to all known worldwide species is given.

Materials and methods
Specimens were collected by hand using a brush, cleared in lactic acid and then mounted in Marc André II solution. They were studied with a Nikon Eclipse 80i microscope.
Labial type is named after Fjellberg (1999). Labium areas and chaetal nomenclature follow Massoud (1967) in D' Haese's (2003) modification. Chaetae on anal valves are named following Yoshii (1996). Chaetae on the furcal area are classified in accordance with Weiner (1996). The formulae of pseudocelli, parapseudocelli and pseudopores are their number on half-tergum (dorsally) or half-sternum (ventrally). The description of tibiotarsal chaetotaxy is based on Deharveng's (1983) scheme and is expressed as a total number of chaetae and also number of chaetae in whorls C, B, and A+T, for example: 22 (3,8,11).
thoracic segments 1 m unpaired pseudopore. The holotype and 23 paratypes (15 females and 8 males) are deposited in Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences; 3 paratypes (2 females and 1 male) in Institute of Systematics and Evolution of Animals, Polish Academy of Sciences.
Description. Body white in alcohol. Length of body 1.1-1.7 mm in females, 0.9-1.1 mm in males; holotype 1.6 mm. Shape of body cylindrical with anal spines on papillae. Anal spines 0.7 times as long as inner edge of hind unguis.
Ecology. Under moss on dead-and-down wood in the Korean pine forest. Derivatio nominis. Named for the national park in which the species was found. Discussion. The new species can easily be distinguished from all known congeners due to the unique number of dorsal and ventral pso. Thus, it shares the presence of ventral pso only with U. varicellata, but clearly differs from the latter in their number (0/000/0001(0) in the new species vs 2/000/0112 in U. varicellata). Dorsal pso formula of the new species is most similar although not identical to that of U. tunguzica (32/133/33333 vs 32/133/33332 in U. liangshuiensis sp. n.). Existed differences in ventral psx formulae (3/000/2210(1)00 in the new species, 2/000/221200 in U. schilovi, 2/000/221100 in U. tunguzica, 2/000/210000 in U. varicellata, and 2/000/221200 in U. yanensis) can also be used in separation of the known species (see also key below).