A review of the genus Monema Walker in China (Lepidoptera, Limacodidae)

Abstract Four species and one subspecies of the genus Monema Walker, 1855 are recognized from China, in which Monema tanaognatha Wu & Pan sp. n. is described as new, Monema coralina Dudgeon, 1895 and Monema meyi Solovyev & Witt, 2009 are newly recorded for China. The female of Monema meyi is reported for the first time. Monema nigrans de Joannis, 1901 and Monema melli Hering, 1931 are synonymized with Monema flavescens Walker, 1855. Cnidocampa rubriceps Matsumura, 1931 is regarded here as a subspecies of Monema flavescens Walker, 1855. The photographs of moths and their genitalia are given. A key to the species of the genus is provided.


Introduction
The genus Monema was erected by Walker in 1855, based on the type species, Monema flavescens Walker, 1855.
Prior to the present study the genus included the following species: M. flavescens Walker, 1855, M. nigrans de Joannis, 1901, M. coralina Dudgeon, 1895 (Matsumura, 1931), M. melli Hering, 1931 andM. meyi Solovyev &Witt, 2009 and it is distributed in Nepal, Bhutan, China, Far East of Russia, Korea, Japan, and northern Vietnam (Hering 1913(Hering , 1933Solovyev 2008;Solovyev and Witt, 2009;Yoshimoto 1993Yoshimoto , 1994. The diagnosis of the genus is given below. In China three taxa have been recorded (Cai 1981;Inoue 1992;Wu 2005Wu , 2012Wu and Fang 2010) up to now. In this paper, four species are reported for China, including one species described as new to science and two species newly recorded for China. Monema nigrans and M. melli are synonymized with M. flavescens. Cnidocampa rubriceps is regarded here as a subspecies of M. flavescens.

Materials and methods
Material examined for this study originates from the insect collections of the Institute of Zoology, Chinese Academy of Sciences (IZCAS), Beijing, P. R. China. All types of new species are deposited in IZCAS Photographs of moths and their genitalia were captured using Canon-EOS-7D with the help of micro-lens. Standard methods of dissection and mounting in Euparal follow Holloway et al. (1987). Description. Moths medium-sized, body yellowish. Male antennae filiform and thicker than in female. Labial palpi extremely long, more than three times eye diameter. Forewings with R 3 + R 4 stalked from R 5 and R 2 stalked with their stem. Hindwings with M 1 and Rs stalked. Forewings with two narrow brown fasciae running from apex to 3/4 and 1/3 of inner margin respectively; basal part of forewing bordered by proximal fascia yellow, rest brown. Hind tibiae with two pairs of spurs. Male genitalia: tegumen narrow; uncus narrow and long, usually with short ventral process at apex; gnathos narrow and long, nearly as long as uncus; juxta with lateral elongate process or spines; valva elongate, with apically saccular process; saccus usually long and large, more than half of valva's width.
Female genitalia: posterior apophysis long, anterior apophysis very short and less than the half length of posterior one; sclerotized exterior flap at posterior margin of ostium bearing minute hair; ductus bursae very long, more than the half length of the abdomen, base narrow and straight, apical part wider and spiraled; corpus bursae ovate, large; a pair of signa trigonal, bearing spines.
The larva belongs to the nettle-type, and is known only for M. flavescens. Its final instar larvae are 19-25mm in length. Head yellowish brown. Thorax yellowish green. Dorsum with a large purple-brown spot shaped as a dumbbell. Subdorsal scoli on T2-A9 and lateral scoli on T2, T3 and A2-8 ( Fig. 22) (Long et al. 2008).
The cocoon of M. flavescens Walker is very hard and shaped as a sparrow-egg. It is white, with longitudinal brown stripes (Fig. 23).
The genus is related to Hyphorma Walker, 1865, but differs from the latter by the shorter terminal segment of the labial palpi and the stalked R 2 and R 3-5 in the forewings. Scopelodes Westwood, 1841 and Phocoderma Butler, 1886 also have very long palpi, but the absence of a tuft of hair in 2nd or 3rd segments distinguish them from Monema (Hering 1931). Description. Wing expanse 30-32 mm in male, 35-39 mm in female. In male genitalia, the juxta is short and ends in 1-3 long spines each side. In female genitalia, the sclerotized base of ductus bursae is diagnostic.  flavescens. Solovyev and Witt (2009) treated M. flavescens var. nigrans as a full species. However, the black form (var. nigrans ) and the normal form (flavescens) are from the same population and the var. nigrans do not show any differences in the male or female genitalia with flavescens. Therefore we treat M. flavescens var. nigrans merely as a dark form. In Guiyang 2.75% of the population of flavescens belonged to the black form; the black individuals can interbreed with the non black individuals and produce fertile offspring (Long et al. 2008). Distribution. Taiwan. Remarks. Cnidocampa rubriceps is treated here as a subspecies of Monema flavescens because the male genitalia have the same structure, except for the aedeagus that is longer in ssp. rubriceps than in ssp. flavescens.
Male genitalia: tegumen narrow; uncus narrow and long, ventrally with short process on apex; gnathos narrow and very long; juxta U-shaped, each lateral bar with distal tuft of long spines; valva elongate, with a strong short apically saccular process; saccus long and relatively narrower than that of flavescens; aedeagus slightly longer than valva, narrow and straight.
Remarks. The abdomen of the female from Xizang is missing. The species is reported for the first time in China.