A contribution to Asian Afidentula Kapur (Coleoptera, Coccinellidae, Epilachnini)

Abstract Two new species of Afidentula, Afidentula dentata sp. n. and Afidentula jinpingensis sp. n. are described from China. Afissa siamensis Dieke is moved to Afidentula comb. n.. All three species are described and illustrated, and a distribution map is given. A key to Asian species of Afidentula is updated. Diagnostic similarities and differences between Afidentula and Afidenta are discussed and illustrated.


Introduction
The genera Afidentula Kapur, 1958 andAfidenta Dieke, 1947 belong to the tribe Epilachnini Mulsant, 1846, the group of phytophagous Coccinellidae. The taxonomy and nomenclatural history of species of both genera have been confused for decades.
The genus Afidenta was established by Dieke (1947) for species having bifid claws with a sharp basal tooth and sixth abdominal ventrite of female not longitudinally divided. Afidenta mimetica Dieke (=A. misera (Weise)) was designated as the type species. Other two species, A. minima (Gorham, 1894) and A. bisquadripunctata (Gyllenhal in Schönherr, 1808) were placed in this genus at the same time, although Dieke noted that the mandibles and male genitalia of A. bisquadripunctata were different from the type species of Afidenta. Kapur (1958) established the genus Afidentula with Epilachna manderstjernae Mulsant as the type species and distinguished it from Afidenta by the antennae subequal to the width of the head with a relatively thick and compact club and subtriangular mandibles with three teeth and without any additional denticulations or serrations. Kapur (1958) also pointed that both A. minima and A. bisquadripunctata should not belong to Afidenta but transferred only A. minima to Afidentula. Subsequently, Afidentula himalayana Kapur, 1963 from India andA. thanhsonensis Hoang, 1977 from Vietnam have been described, and several other mainland Asian species were added to that genus, e.g. Epilachna stephensi was transferred to Afidentula by Booth and Pope (1989). Bielawski (1963) transferred the Papuan Epilachna aruensis Crotch to Afidentula and Bielawski (1963Bielawski ( , 1965 and Jadwiszczak (1986) added further new species from New Guinea.
Li in Li and Cook (1961) described Afidenta arisana from Taiwan, which was moved to Afissula Kapur by Zeng (1995). Pang and Mao (1979) transferred Afissa siamensis Dieke into Afidenta and moved A. bisquadripunctata into Afidentula. Chazeau (1975Chazeau ( , 1976 studied African Epilachninae, and described 29 new species, which included nine species of Afidenta. Fürsch (1986) revised species of Afidenta describing five new species and included 25 species but not Chazeau's (1975Chazeau's ( , 1976 species. Jadwiszczak and Węgrzynowicz (2003) listed 39 species belonging to Afidenta (of which 37 have been distributed in Africa and two in Asia) and 18 species of Afidentula (11 species distributed in mainland Asia and seven in New Guinea and Aru Island). Tomaszewska and Szawaryn (2013), and Szawaryn and Tomaszewska (2013) revised Asian and Papuan species of Afidentula. They concluded that the mainland species of the Afidentula form uniform group which can be characterized by: comparatively small body, brown colour with black markings on elytra, compact and short mandibles provided with three apical teeth of which only middle one is sometimes weakly serrated, maxilla with basistipes and mediastipes separated entirely or almost so, terminal labial palpomere shorter than subterminal one, tibial spurs absent, tarsal claw with basal tooth present, and sternite VIII in females undivided. Species from New Guinea and Aru Island are considerably different having among others the body much larger and entirely black or black with orange spots on elytra, mandibles large and thin laterally with apical and subapical teeth, often additionally serrated, elytral epipleura complete (incomplete in Afidentula), the distance between antennal sockets about three or four times greater than a distance between antennal socket and inner margin of eye (in Afidentula this distance is about twice as great), coxites with styli and the tegmen with stout parameres. For New Guinean species Szawaryn and Tomaszewska (2013) proposed a new genus Papuaepilachna and for A. aruensis form Aru Island a new genus Lalokia. Szawaryn et al. (2015) conducted phylogenetic research on Epilachnini based on molecular and morphological data. According to this study, both Afidenta and Afi-dentula have not been recovered as monophyletic groups and each of them has been redefined. Studied species of Afidenta from Africa formed monophyletic clade with Asian mainland species of Afidentula and exclusion of the Papuan species from Afidentula has been confirmed by the study. From among two species of Afidenta from Asia, the type species (A. misera) was studied and it formed a separate clade by itself, based on the following combination of characters: ventral surface of the mandible densely tuberculate, galea transversely oval, terminal palpomere of labium distinctly narrower than penultimate one, metaventral postcoxal lines joined or almost so on metaventral process, forming somewhat w-shaped line along discrimen, male tergite VIII rounded apically and styli absent. The definition of Afidentula has been extended after inclusion of African species of Afidenta and some Malagasy Epilachna and Henosepilachna, and it has been characterized by the following combination of characters: gular sutures shorter than half-length of gula, mandibular incisor edge without teeth, terminal maxillary palpomere weakly elongate, expanded apically, labial apical palpomere distinctly narrower than penultimate palpomere and styli absent.
Based on the results of the phylogenetic analyses of Szawaryn et al. (2015), the present paper describes two new species of Afidentula from China, A. dentata sp. n. and A. jinpingensis sp. n. The study of Afidenta siamensis permits the move of this species from Afidenta to Afidentula as Afidentula siamensis comb. n., confirming with this that Afidenta now includes only one species.

Material and methods
The external morphology was observed with a dissecting stereoscope (SteREO Discovery V20, Zeiss and Leica Mz Apo). The following measurements were made with an ocular micrometer: total length, length from apical margin of clypeus to apex of elytra (TL); total width, width across both elytra at widest part (TW=EW); height, from the highest part of the beetle to elytral outer margins (TH); head width in front view, widest part (HW); pronotal length, from the middle of anterior margin to margin of basal foramen (PL); pronotal width at widest part (PW); elytral length, along suture, from the apex to the base including scutellum (EL). Male and female genitalia were dissected, cleared in 10% solution of NaOH by boiling for several minutes, and examined with an Olympus BX51 and Leica compound microscope.
Morphological characters were photographed with digital cameras (AxioCam HRc and Coolsnap-Procf & CRI Micro*Color), connected to the dissecting microscope. The software AxioVision Rel. 4.8 and Image-Pro Plus 5.1 were used to capture images from both cameras, and photos were cleaned up and laid out in plates with Adobe Photoshop CS 8.0.
Coccinellidae morphological terms follow Ślipiński (2007) and Ślipiński and Tomaszewska (2010). Type specimens designated in the present paper are deposited at SCAU-the Department of Entomology, South China Agriculture University, Guangzhou, China.
Afidentula is also similar to Afissa Dieke (=Afissula Kapur) in general appearance, but it can be separated by having antennae distinctly shorter than width of the head and with at least antennomeres 7 and 8 subquadrate (in Afissa antennae are longer than width of head and have antennomeres 3-8 elongate) and tibiae without apical spurs (tibial spurs present in Afissa).
Monographic revision of all Epilachnini genera based on the results of phylogenetic analysis is in preparation (Tomaszewska and Szawaryn, in prep.) and richly illustrated; detailed descriptions of all genera will be provided there.

Figures 2, 5
Afissa siamensis Dieke, 1947: 127. Afidenta siamensis: Pang and Mao 1979: 119;Cao 1992: 221;Ren et al. 2009: 250. Diagnosis. This species is most similar to A. dentata and A. stephensi (known from India and Pakistan) but can be distinguished from both by having pronotum with two large black oval spots, apex of penis with small sharp process directed outwardly (Fig.  2a-c, 2l) and apex of penis guide curved outwardly (Fig. 2m-n). Body short oval, dorsum strongly convex, densely pubescent (Fig. 2a-c). Head yellowish brown. Pronotum yellowish brown except anterior corners yellowish white, with two large black, triangularly-oval spots. Scutellum yellowish brown. Elytra yellowish brown, with 14 rounded black spots, arranged as in Fig. 2a-c. Underside yellowish brown, except metaventrite and middle area of abdomen black. Epipleura and legs yellow.
Male genitalia. Penis short and stout, strongly curved at base, apex with small and sharp process directed inwardly, capsule inconspicuous (Figs 2l). Tegmen stout ( Fig. 2m-n); penis guide in lateral view widest at base and narrowing to apex, strongly curved outwardly at apical 1/4, apex pointed (Fig. 2m); parameres slender, distinctly shorter than penis guide (Fig. 2m); penis guide in ventral view flattened and asymmetrical at apex, lateral margins almost parallel, apex blunt (Fig. 2n).
Specimens examined. Holotype. Nan, Siam, Jan. 27/28, Cockerell/ Type No. 57138 USNM/ Afissa siamensis Dieke, holotype. CHINA, Yunnan Prov.: 1 male, Jiluoshan, Xishuangbanna National Natural Reserve, Mengla County, 6.v.2009, Wang XM et al. leg;1 female, Lafu, Menglian County, 1130m, 7.v.2008Guizhou Prov.: 3 males, Dadugang, Badu Town, Ceheng County, 15.x.2006, Wang XM leg. Distribution. China: Guizhou, Yunnan; Thailand. Remark. Pang and Mao (1979) transferred Afissa siamensis Dieke into Afidenta without any explanation. However, a detailed examination of A. siamensis and Afidenta misera left no doubt that they do not belong to a same genus, and that diagnostic characters of A. siamensis match Afidentula. Thus this species in formally transfered to the genus Afidentula. Diagnosis. This species is most similar to A. siamensis in general appearance and colouration, e.g. having two mutual maculae on elytra along suture (anteriorly and medi-ally) but can be distinguished from the latter by having pronotum with a large black spot which almost covers entire surface of the pronotum leaving only lateral and anterior margins brown ( Fig. 3a-d), and apex of penis with two tooth-shaped appendices inwardly ( Fig. 3f-g). In A. siamensis, pronotum has two large black spots, and apex of penis has a small and sharp process directed outwardly (Fig. 2a- (Figs 3a-d). Head yellowish brown. Pronotum mostly black with only lateral and anterior margins yellowish brown (Fig. 3c). Scutellum yellowish brown. Elytra yellowish brown, with 14 rounded black spots arranged as in Figures 3d; spots may connect to each other forming transverse bands (Fig. 3a, b). Underside yellowish brown, except meso-, metaventrite and middle area of abdomen dark brown. Epipleura yellowish brown, except areas close to meso-and metaventrite dark brown. Legs yellow.
Male genitalia. Penis stout, strongly curved, apex simple and pointed, capsule with an expanded outer arm and a small inner one (Fig. 4e). Tegmen stout (Fig. 4f); penis guide in lateral view subparallel along 4/5 of its length and hook-like at apex; apex curved outwardly; parameres extremely slender, distinctly shorter than penis guide. Distribution. China (Yunnan). Etymology. The specific epithet is named after Jingpin County, China, the type locality of this ladybird.