A Review of the Genus Miresa Walker in China (Lepidoptera: Limacodidae)

Eight species of the genus Miresa Walker are recognized in China including two new species, M. fangae Wu & Solovyev and M. polargenta Wu & Solovyev, described herein. M. burmensis Hering species is reported for the first time in China. The M. argentifera kwangtungensis Hering, 1931 taxon is raised to full specific status. The lectotypes are designated for the following 5 taxa: M. bracteata Butler, 1880 (♂, Natural History Museum, London); M. fulgida Wileman, 1910 (♂, Natural History Museum, London); M. bracteata var. orientis Strand, 1915 (♂, Rijksmuseum van Natuurlijke Historie, Leiden); M. argentifera kwangtungensis Hering, 1931 (♂, Zoologisches Museum der Humboldt Universität zu Berlin) and M. urga Hering, 1933 (♂, Zoologisches Museum der Humboldt Universität zu Berlin). The photographs of moths and their genitalia are given, a key to the Chinese species of the genus is provided, and the distributional maps are also given.


Introduction
The genus Miresa was erected by Walker in 1855 and it included 5 species from the Indian region. The type species, Nyssia albipuncta Herrich-Schäffer [1854] 1850-1858, was designated subsequently by Moore (1882-3: 128). The genus is presently considered pantropical -occurring in Asia, Africa, and America (van Eecke 1925;Hering 1928Hering , 1931Hering , 1933Dyar 1935;Epstein, Corrales 2004) and includes more than 30 species. The check lists of the genus were given more than 70 years ago (van Eecke 1925;Hering 1928Hering , 1931Hering , 1933Dyar 1935). These lists were slightly changed later by transferring some species to other genera, but these investigations involved just a few species and were connected with local faunistic studies (e.g. Janse 1964). Therefore, the lists are debatable at present. The recent diagnosis of the genus was given by Holloway (1986) and concerned Asian species only, although the monophyly of Miresa worldwide remained not evident and not supported. The genus needs revising worldwide to determine if taxa presently in the genus belong elsewhere. Perhaps it ranges to South-East Asia only, and the Asian and American members may belong to other genera. The main aim of this paper is to overview Chinese Miresa to observe morphology and biology, and make some notes to their distribution and nomenclature. The examination of Chinese Miresa is urgent due to their economical importance. The larvae are famous pests of various agricultural plants and attribute to the "nettle"-type (Godfray et al. 1987), bearing stinging spurs that can cause burning pain and itching as a result of their contact with a human skin. No outbreaks in China have been reported up to now, but the biological control of Miresa population size is recommended. Up to now 5 species of the genus were recorded from China (Leech 1899;Hering 1931Hering , 1933Cai 1981Cai , 1982Inoue 1992;Fang 1997), but the list needed improvement and reexamination of Chinese fauna. Misidentifications made in previous investigations were found; 3 species are added to Chinese fauna, including 2 new to science and 1 newly recorded species.

Materials and Methods
Material examined for this study was based on the insect collections of the Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. China (IZCAS). Material from the Museum Witt Munich, Germany (MWM), and collections of A. V. Solovyev (CSAV) were also examined for this study. The type specimens of all mentioned taxa examined are kept in the Natural History Museum, London, United Kingdom (NHM), Zoologisches Museum der Humboldt Universität zu Berlin, Germany (ZMHB), Nationaal Natuurhistorische Museum ("Naturalis") (Leiden, Netherlands (formerly the Rijksmuseum van Natuurlijke Historie), (RMNH), and Museum National d'Histoire Naturelle, Paris, France (MNHN). The photographs of moths and their genitalia are given. Standard methods of dissection and mounting in Euparal described by Holloway et al. (1987).
The Asian members of the genus are middlesized limacodids with yellowish brown ground colour. The male antennae are broadly bipectinate in basal part. The labial palps are somewhat upcurved, with a very small 3rd segment. The thorax is usually yellow or pale brown. The forewings have diagnostic silver pattern including S-shaped post-median fascia, terminal fascia and a medial silver spot; some of these silver patterns are absent in some species (Figures 1-10). The forewing ground color is paler below the cell. In the forewing the vein R 1 is slightly curved and close to Sc; the veins R 3 +R 4 are branched from R 5 ; the medial stem is not divided. The hind tibia has only one pair of spurs, a condition found in other Limacodidae, although two pair also commonly occurs.
The male genitalia are not strongly modified  usually bears strongly sclerotized apical spur or strong and well defined apical sclerotization. The gnathos is single and strong. The valvae are elongated, without saccular processes. The juxta is simple and flattened. The saccus is short. The aedeagus is long, much longer of the valva, often curved with defined coecum aedeagus basales, and has an apical spur. The vesica is without cornuti.
In the female genitalia the ductus bursae is spiral; the corpus bursae is ovoid, and bears paired signa (Figures 20-25), the signum can be absent in some species (Figure 20).
The larvae and their host plants are known only for 2 Chinese species. The larvae are of the nettle-type with long scoli; the dorsal scoli on segments A2-A6 are reduced usually. Coffea (coffee), Theobroma, Mangifera (mango), Buchanania, Alseodaphne, Terminalia, Aleurites, Canarium (olive), Cinchona, Vernicia, Eugenia, and Manilkara are known genera of hosts (Piepers, Snellen 1900;Hering 1931;Holloway 1986;Robinson et al. 2001Robinson et al. , 2007. The genus can be confused with Narosoideus Matsumura, 1911, but is well distinguished by the presence of a silver spot or fascia in the forewing. Most probably, the genera Miresa Walker and Narosoideus Matsumura are closely related and present a monophyletic lineage. Moreover, both genera are probable synonyms distinguished only by presence or absence of any silver pattern on the forewings (Holloway 1986: 88). Both, Miresa and Narosoideus, have yellowish brown ground color with pale thorax. Their forewings have a similar pattern, almost monotonous ochrebrown, with distinct pale area below the discal cell and usually with a well defined S-shaped post-median fascia which is often silver in Miresa and dark in Narosoideus (Solovyev and Witt 2009: 106). The male and female genitalia are weakly modified. References : Cai 1982: 32, 1987.

Diagnosis:
The species is similar to fulgida Wileman, 1910 externally, but defined by the absence of the veins proximal to the silver spot extend silver among them and by the absence of the proximal silver spot in bracteata (Figures 1, 2).  yellow just above subdorsal scoli (Holloway 1986: 89;homology sensu, Epstein 1996). Piepers, Snellen (1900: 73)  Nomenclatorial notes: The species Miresa bracteata Butler, 1880 was described on the specimens of each sex kept in NHM. The lectotype: male, with following labels: 1rounded with red frame and printed text "Type"; 2 -rectangle, yellowish, handwritten by brown (faded black) ink text "Miresa | bracteata | Butler Type" and in other side "Darjiling | 79·57"; 3 -rectangle, blue, with black printed text "genitalia slide | No." and black inked "194 " (Figure 2). This male is supplied with additional lectotype label with corresponding text. The other syntypical specimen, female, is designated as paralectotype. Hering, 1931 (Figures 3, 12, 21, 27)

Diagnosis:
The species is distinguishable from other Chinese congeners by having almost uniform dark brown forewings with an ochreous post-median fascia and with a compact silver medial spot; the external and post-median silver fasciae are absent. The species is similar by the forewing pattern to the other Asian members of the genus, M. albipuncta (Herrich-Schäffer, 1853); M. pyronota Hampson, 1910;and M. sibinoides Hering, 1931 known from India and Sri Lanka, but differs in having the aedeagus curvation more than 45° (Figure 12). This diagnostic feature should be verified using more materials from China and the Indian region.

Diagnosis:
The species is similar to demangei de Joannis and bracteata Butler, but its silver medial spot in forewing is smaller, with additional veins proximal to the silver spot extend the silver along them and additional proximal silver spot ( Figure 5).  Larva: It is of the nettle-type, with four rows of scoli. The mature larva has long dorsal scoli present on segments T3, A1, and A7 only; subdorsal scoli of segments T2, T3, and A2-A9 are short, well developed. The larva is green with pair of dorsal, waved, edged by dark green, white fasciae, running from A1 to A7 where they are joined together; with white, edged by dark green, dorsal, ovoid rings between T2 and T3, T3 and A1. The food plants: Camellia spp., Canarium album (Lour.) Rausch. (Burseraceae) (Hering 1931: 682;Robinson et al. 2001Robinson et al. , 2007. There is one generation per year in Xishuangbana Prefecture, Yunnan Province. It overwinters as the mature larva in the cocoon. The larva feeds during late June to October.

Diagnosis:
The species is well recognized from other congeners by uniform dark forewing coloration and deep yellow thorax ( Figure 6). Silver medial spot and post-median fascia are absent; the silver terminal fascia is indistinct. In male genitalia the narrower valva and uncus with two apical strongly sclerotized lobes are diagnostic (Figure 15).

Remarks:
The taxon Miresa argentifera kwangtungensis Hering, 1931 is raised to full specific status because of its strong morphological differences with nominate subspecies Miresa argentifera argentifera. The taxon kwangtungensis is much darker than argentifera. The forewing pattern is rather different with a single not well defined terminal silver fascia in kwangtungensis and with both, terminal, and post-median, fasciae in argentifera. The male genitalia of kwangtungensis differ considerably from argentifera and from other members of Miresa, and are characterized by the unique for Miresa morphology of uncus; it has two apical strongly sclerotized lobes. So, the phylogenetic relationships between both, kwangtungensis and argentifera, are not proved and the taxon kwangtungensis is regarded as a separate species.
Perhaps, the species kwangtungensis was misidentified as Miresa decedens Walker, 1855 by Leech (1899: 104) because of external similarity of both species. Miresa decedens ranges to the Indian region only.

Diagnosis:
The species is similar externally to M. fangae Wu & Solovyev, sp. n., but the forewings are more elongated with pointed apex (Figure 7); the aedeagus bears the large, apical, dorsal, rounded, crest-shaped process ( Figure 16). dark reddish brown with yellowish brown area below cell; the post-median fascia is waved, and indistinct excepting its inner margin part; the terminal fascia is composed of a row of the silvery dots. The hindwings are reddish brown.
In the male genitalia the uncus is short and wide; the gnathos is well developed, wide, apically hooked, and gradually slenderized distally; the valvae are narrow and long, slightly tapering to a rounded apex; the juxta is sclerotized weakly, shield-shaped; the aedeagus is slender and long, slightly arched proximally, and contains 3 flattened, compact, triangular spurs, the ventral one is wide, gradually narrowed to the apex ( Figure 18).  ( Figures 10, 19, 25, 33)

Diagnosis:
The species is similar to M. argentifera Walker and M. fangae Wu & Solovyev, sp. n., but differs by the forewing with silvery veins M 2 and CuA 2 proximally to the silver post-median fascia; darker hindwings. In male genitalia the robust and rounded apically uncus, S-shaped in lateral view gnathos, shorter, almost straight aedeagus bearing apically a characteristic craniad dorsal triangular process and not spurlike (as in argentifera) ventral process are diagnostic and well separate polargenta from these similar species.

Description:
The wing expanse is 26-33 mm. The head and thorax are yellowish brown; the tegulae and metathorax are edged with reddish brown (Figure 10). The abdomen is reddish brown. The forewings are dark reddish brown, but are pale reddish brown below cell; the post-median fascia is waved; the veins M 2 and CuA 2 are silvery before post-median fascia; the terminal fascia is composed of a row of silvery dots. The hindwings are reddish brown.
In male genitalia ( Figure 19) the uncus is short and wide, rounded apically; the gnathos is well developed, apically hooked; the valvae are narrow and long, tapering to a rounded apex; the juxta is sclerotized weakly, shieldshaped; the aedeagus is narrow and long, almost straight, apically has 3 triangular processes on the top.
In female genitalia ( Figure 25) the anterior apophyses are as short as 1/3 of the posterior ones; the ductus bursae is very long; the corpus bursae is ovate, large; the paired signa elongated along symmetry axis, strongly widened cranially, bearing spines.

Biology:
The moths were collected in May, June-mid July and early August on the altitudes of 1100-1800 m.

Etymology:
The name is derived from Greek "poly" (= numerous) and "argentum" (= silver), corresponding to the numerous silvery stripes on the forewing.

Conclusions
The Chinese species of the genus Miresa Walker, 1855 are reviewed. In total 8 species were found, and 3 of them are newly recorded. Two of these species  Hering, 1931 ( , ZMHB); and M. urga Hering, 1933 ( , ZMHB).
The fauna of the genus in southern China is characterized by hi-level biodiversity, as well as biodiversity of Xizang (Southwestern China) which belongs to Indian fauna; whereas the provinces Yunnan, Guangdong, and Hainan are related to Northern Vietnamese fauna.
The preimaginal stages and larval host plants are known just for 2 species in China in spite of economic importance of the species as pests of different cultural plants. Further investigations of host plants are urgent.