Notes on and key to the genus Phengaris (s. str.) (Lepidoptera, Lycaenidae) from mainland China with description of a new species

Th e lycaenid genus Phengaris (s. str.) from mainland China is briefl y characterized, and a short identifi cation key presented. Phengaris xiushani sp. n. is described and illustrated from northwestern Yunnan. Th e new species is similar to P. daitozana from Taiwan with respect to the wing maculation in having a whitish upperside and much smaller spots on the underside. Genitalia features are similar to Phengaris (Maculinea) nausithous from the western Palaearctic region. Th e type specimens are kept in the Insect Collection, South China Agricultural University, Guangzhou, China (SCAU), and the “S enckenberg Museum für Tierkunde” in Dresden, Germany (MTD).


Introduction
Th e large blues of the lycaenid genus Phengaris Doherty, 1892 (s.str.) hitherto only encompassed three species: P. atroguttata Oberthür, 1876, P. albida Leech, 1893 andP. daitozana Wileman, 1908.Th ese were distributed in the area between the Oriental and Palaearctic region of E. Asia.Recently, Fric et al. (2007) treated the Palaearctic genus Maculinea Van Eecke, 1915 as a synonym of Phengaris and divided the genus (s.lat.) into four species groups and eleven species.
Th e large blues of former Maculinea Van Eecke, 1915 (s. str .;see Balletto et al. in press, on recent discussions of nomenclature) belong to the most intensively studied group of butterfl ies in Eurasia, which is probably due to their "obscure" biology and ecology (Als et al. 2004;Barbero et al. 2009;Nash et al. 2008;Pech et al. 2004;Th omas and Settele 2004;Th omas et al. 2009).Th eir specialized habitat requirements have made them vulnerable to global change (Settele and Kühn 2009), including climate change and habitat alteration.Large Blue populations have suff ered severe declines in Europe, and one species, M. arion (Linnaeus, 1758) went extinct in the UK in the 1970s, but was then reintroduced from Sweden (Th omas et al. 2009), which sparked increased interest in the conservation and habitat restoration of this species.Four Maculinea species are listed in the IUCN Red List of Th reatened Species as 'near threatened' and M. rebeli Hirschke, 1904 as 'vulnerable'.Th ree species are included in Annexes II and IV of the European Habitats' Directive, and all European species are being monitored and intensively studied under the European research projects MacMan and CLIMIT (www.climit-project.net)(Settele et al. 2005;Settele and Kühn 2009).
In the course of a Chinese-German workshop on butterfl y conservation held in Guangzhou in December 2009, we examined specimens kept in the Insect Collections of the South China Agricultural University, which led to the discovery of a Phengaris species which had not previously been reported.We herewith describe the new species.

Materials and methods
We investigated 5 dried specimens collected by netting during day time from Nujiang County on the 24 th of July 2006.Pictures of mounted adults were taken with a Nikon Coolpix 990 digital camera.Th e whole abdomen of the holotype was rem oved and macerated in boiling 10% NaOH liquid for 3-4 minutes.Th e genitalia was checked and mounted on a slide in glycerin under the Leica 12.5 stereoscope.Th e genitalic photos were taken with a Nik on Coolpix 990 connected to an eye lens of the stereoscope.All the images were pr ocessed with Adobe Photoshop 6.0.Th e type specimens are deposited in the Insect Collections, Department of Entomology, South China Ag-ricultural University, Guangzhou, China (1 male holotype and 3 female paratypes) and the "Museum für Tierkunde" in Dresden, Germany (1 male paratype).Male.Forewing length 21 mm, antenna length 9.5 mm.Forewing upperside ground colour whitish, with black margin gradually broadened from tornus to the mid of termen and then sharply widened to apex, where overlapped with three darker black dots, one traceable smaller spot each in the mid of space M3 and distal cell.Cilia are white checkered with black.Underside ground color same as upperside, with black spots in mid and distal cell, and postdiscal, submarginal and marginal series.Postdiscal series with the spots in spaces M1 and M2 prominently shifted outwardly.Submarginal series is much broader than marginal series.

Phengaris xiushani
Hindwing upperside ground color similar to that on forewing, with traceable markings which shine through from the underside.Cilia almost white, with fi ne black checkers at the end of each vein.Underside ground color same as upperside, with black spots consisting of discal, postdiscal, submarginal and marginal series, as well as a black spot each at basal and mid space Sc+R1.Th e black spot of postdiscal series in space CuA2 shifted outwardly.
Female.Similar to male, but slightly larger, black margins of both wings are well developed.
Diagnosis.Superfi cially, the species is similar to P. daitozana as shown in Shirôzu's book (1960) from Taiwan in having whitish ground color on upperside and smaller black spots on underside, but the black spot in space CuA1 of the postdiscal series is distinctly shifted outwards, also the valva of the male genitalia with its dorsal part is not so well infl ated distally and, compared with drawings in Higgins (1975), has similar genitalia to the Palaearctic P. (Maculinea) nausithous (Bergsträsser, 1779).Th e species is also easily recognized from P. atroguttata (Figs 1, 2, 10) and P. albida (Figs 7,8,11) by the wing maculation and genitalia features.
Th ere are several taxa names published previously in mainland China and neighboring countries now treated as subspecies of P. atro guttata or separate species: juenana  (Forster, 1940), showed that lampra (Röber, 1926) belongs to P. atrogut tata in having a black spot at basal cell C, whereas intermedia Oberthür, 1916 is identical to P. albida.Th ough the type of juenana (Forster, 1940) was not inspected in our study, we can postulate from Forster's original description that the taxon is related to lampra (Röber, 1926) and belongs to P. atroguttata, which was verifi ed by Huang (2003).
Th e name dohertyi Hemming appeared in D'Abrera (1993) for a taxon from Naga Hills and northern Myanmar, but could not be found in any further literature.It is possible that the name dohertyi was never published (John E. Chainey, personal communication).
Biological notes.Th e species occurs together with P. atroguttata in one locality, which we assume is their usual habitat within undisturbed forested mountains (Fig. 12); many adults were fl ying together.Only one locality was encountered during a 6 days fi eld trip.
Etymology.Th e specifi c name refers: (a) to the beautiful mountain on the slopes of which it was found (Xiu-Shan in Chinese means "beautiful mountain"), and (b) more importantly we dedicate this species to Dr. Xiushan LI who brought the two authors of this description together and who has committed much of his life to research on ecology and conservation of butterfl ies (e.g.Li et al., 2006Li et al., , 2010)).