Latidrymus , a new genus of Drymini from the Oriental Region ( Hemiptera : Heteroptera : Rhyparochromidae )

Latidrymus gen. nov. (Hemiptera: Heteroptera: Rhyparochromidae: Rhyparochrominae: Drymini) is described, with four new species included: L. puskasi sp. nov. (type species) from India, Thailand and Laos, L. elevatus sp. nov. and L. fl avus sp. nov. from Laos, and L. zetteli sp. nov. from northeastern India. A key to the species and a distribution map are provided.


Introduction
The superfamily Lygaeoidea, predominantly contains ground-dwelling species feeding on seeds, and is a rather neglected group of Hemiptera due to their small body size.About half of the described species of Lygaeoidea belong to Rhyparochromidae.The vast majority of these tiny to middle-sized species (between 1.3 mm of Lilliputocoris Slater &Woodward, 1979 and17 mm of Dieuches Dohrn, 1860) are phytophagous and are distributed all over the world except some minor islands and territories devoid of vegetation.Some are good fl yers and have broad distributions, but many species are fl ightless.The family is divided to 15 tribes (SLATER & WOODWARD 1982), ranging from monotypic to very species-rich.The third most diverse tribe is the Drymini, currently comprising 292 valid species in 57 genera, distributed worldwide except of South America and the majority of the Pacifi c islands, and with rather similar diversity in the Palaearctic, Afrotropical and Oriental Regions (KONDOROSY 2013).
This paper provides the description of a new genus and four included new species of Drymini from the Oriental Region.

Material and methods
Examination of the specimens was carried out using a stereoscopic microscope (Olympus SZ 11).Genitalia were dissected after boiling in KOH solution and stained with Chlorazol Black E. Drawings of genitalia were made partly using a camera lucida, partly based on photographs.Measurements were taken using a micrometer eyepiece.The lengths of head and pronotum were measured not dorsally but in their maximum length.The specimens were photographed with a Nikon D60 digital camera with 60mm/2.8G ED AF-S Micro Nikkor objective with Meike extension tubes and Entangle 0.7.0 software and I used MicroFusion 0.7.4a for photostacking.
For the preparation of the distribution map I used the software Google Earth (version 7. 1.8.3036).
This study is based on specimens deposited in the following institutions:

Description.
Body small, about 2.8-3.5 mm long, general facies rather broadly oval, weakly convex dorsally.Integument and vestiture dull, subshining; head, pronotum, scutellum, and fore wings deeply and rather coarsely punctate, midline of pronotum posteriad to collar, at transversal impression, and at base of posterior lobe as well as Y-or T-shaped median ridge on scutellum impunctate.Dorsum only with very short, inconspicuous pilosity.
Thorax.Pronotum subtrapezoid, with anterior and posterior lobes subequal in length, separated by a strong transverse impression, with a distinctly delimited anterior collar; anterior lobe at transverse impression nearly parallel, rounded at anterior angles; posterior lobe strongly expanded posteriad of transverse impression; lateral margin evenly broadly laminate, terminating abruptly posteriorly, deeply concave at level of transverse impression; posterior margin nearly straight, with a broadly rounded expansion at the base of hemelytra.
Scutellum with distinct, elevated, T-shaped (or slightly Y-shaped) median ridge.Clavus narrow, with three regular rows of punctures; margin of basal portion of corium straight, moderately narrowed in its apical two-thirds therefore connexivum exposed; apical margin of corium straight; endocorium with two regular rows of punctures close to clavus, a third row along apical margin, with some additional punctures laterally.Mesocorium densely punctate, exocorium smooth.Sternum sparsely covered with coarse punctures, mesosternum medially impunctate, on both sides shiny, with extremely fi ne punctures.Metathoracic scent gland ostiole short, peritreme small, evaporatorium reaching about middle of metapleuron.Fore femur slightly incras sate, with a moderately large tooth and with two series of minute teeth ventrally; all tibiae straight.
Abdominal venter almost impunctate (with very fi ne punctures only), with dense white pubescence covering extremely fi nely wrinkled surface.Posterior half of last tergite strongly transversely wrinkled, in male posteriorly bending downward, cup-like.Lateral portions of suture between sterna IV and V curving anteriad, not reaching lateral margin of abdomen; position of trichobothria and spiracles as characteristic in Drymini.Differential diagnosis.Latidrymus gen.nov.can easily be distinguished from other genera of Drymini by the peculiar, broadly explanate and laminate lateral margin of the pronotum, which is only little narrower on the anterior pronotal lobe than width of eyes, and its anteriormost portion is almost perpendicular to the midline of the body, whilst its posterior portion is abruptly, truncately terminated at the humeral angles.Such modifi cation of the lateral margin of pronotum is unique in Drymini.
Drymus Fieber, 1860, which is characterized by a Holarctic distribution with a few species reaching India, is somewhat similar to the new genus, but members of Drymus have a much more narrowly carinate margin of the pronotum, longer and more slender antenna, nearly fully punctate corium, and lack a scutellar ridge (e.g.PÉRICART 1999).
Members of Appolonius Distant, 1901, restricted to tropical areas of the Eastern Hemisphere, have similarly short and thick antenna and projecting eyes, but, among other differences,  they have a very broad and vertical head, and the explanate lateral margin of the pronotum distinctly broadens at the transversal impression (CHOPRA & SINGAL 1982).
Scolopostethus Fieber, 1860 is a morphologically diverse genus distributed in the Old World, but some of the currently included species are clearly not congeneric with the type species (KONDOROSY 2013).Some of these are similar to the new genus, but they always have longer antenna and head, the lateral carina on the pronotum is not evenly broad, they lack a T-shaped carina on the scutellum (sometimes a Y-shaped carina is present), and their fore femur is not strongly incrassate, etc. (PÉRICART 1999).The same features distinguish the new genus also from Eremocoris Fieber, 1860 (Old World, mostly Palaearctic), Faelicianus Distant, 1901 (Philippines and Sulawesi) and Grossander Slater, 1976 (Australian and Oriental Regions), which are also more or less similar to Latidrymus in general appearance (e.g.BERGROTH 1918, KONDOROSY & FÁBICS 2015, PÉRICART 1999).
Austrodrymus Gross, 1965 (South and Western Australia) somewhat resembles the new genus too, but it lacks pronotal collar, and the posterior pronotal margin is not laminate (GROSS 1965).
The Afrotropical genus Testudodrymus Slater, 1993 has very short scape with a tooth-like lateral projection, the lateral and basal margins of the pronotum are straight, it lacks scutellar carina, and has unarmed fore femora (SLATER 1993).Etymology.The generic name is derived from the Latin adjective latus, meaning broad, referring the 'dumpy' shape of the species, and the name of Drymus, the type genus of Drymini.The gender is masculine.Diversity and distribution.The new genus is widely distributed in continental South and Southeast Asia (Fig. 16) from India (Meghalaya, West Bengal, Tamil Nadu) and southeastern China (Fujian) to Sumatra.It contains four species described below and probably also some undescribed.
Antenna short, reaching only about middle of pronotum, scape extending beyond apex of head by one third of its length.Apex of labium not reaching mesocoxae, apex of segment I not reaching base of head.
Pronotum without elevations anteriad of transversal impression (Fig. 6), explanate lateral margin wider than diameter of scape; anterior lobe slightly broader at middle than at transversal furrow; posterior lobe unevenly punctate, punctures anteriad of scutellum partly adjacent or confl uent.
Elevation of scutellum Y-shaped, well-developed (transverse part fully punctate), longitudinal ridge on anterior part elevated.Mesosternum transversely wrinkled at middle.Metacoxae almost touching each other, erected much closer than mesocoxae.
Abdomen almost dull, with very dense fi ne pubescence.Male genitalia: phallus as in Figs 8-9, paramere as in Fig. 10.Phallus is different from any type known so far in Drymini.The endophallic reservoir is most similar to Drymus species (PÉRICART 1999) but among others the penisfi lum is very different.Paramere is rather short and wide, with nearly sickle-shaped sensory arm and apophysis.

Latidrymus elevatus
Structure.Similar to L. puskasi sp.nov.(Fig. 3) but labium reaching end of mid coxae, segment I attaining base of head.Anterior lobe of pronotum provided with a pair of strong elevations close to transverse impression.Pronotum with slightly elevated impunctate midline between collar and middle part of posterior lobe.Lateral margin of pronotum narrower than diameter of scape.Posterior half of pronotum evenly punctate, punctures separated from each other.
Scutellum with a nearly T-shaped elevated carina with impunctate area on transverse part, midline only slightly elevated, impunctate.Mesosternum with very fi ne punctures, medially provided with stronger punctures, submedially transversely wrinkled.Metacoxae almost as far apart as mesocoxae.

Latidrymus zetteli
Structure.Similar to L. elevatus sp.nov.but elevations close to transverse impression on anterior pronotal lobe weaker.Labium reaching apex of mid coxae, segment I reaching base of head.Pronotal lateral margin posteriorly continued to basal margin without a strong incision.Posterior half of pronotum more densely punctate, punctures partly touching each other.Median carina of pronotum indistinct.Scutellum with nearly T-shaped carina.Mesosternum with extremely fi ne punctures, medially with strong punctures, submedially transversely wrinkled.Paramere similar to that of L. puskasi sp.nov, albeit with a more slender sensory lobe (Fig. 11).
Measurements (in mm).Holotype.Total body length 2.84; head: length 0.42, width 0.68, interocular space 0.42; pronotum: length 0.86, width at base 1.22; scutellum: length 0.52, width 0.56; claval commissure length 0.20; length of antennal segments: scape 0.22, pedicel 0.36, basifl agellum 0.36, distifl agellum 0.48; length of labial segments: I 0.28, II 0.26, III 0.21, IV 0.16.Differential diagnosis.In some characters Latidrymus zetteli sp.nov. is transitional between L. puskasi sp.nov.and L. elevatus sp.nov., but differs from both species in the small body and the coloration of the antenna, corium and membrane.It is the only species in the genus in which the dark spot of the endocorium extends beyond the two inner rows of punctures.The pale midline of scutellum is present only in L. elevatus sp.nov.and L. zetteli sp.nov., but only L. elevatus has a continuous dark margin on the membrane and the coloration of the anterior lobe of the pronotum of L. elevatus sp.nov. is much paler than the head (it is similarly dark brown to the head in L. zetteli sp.nov.).Etymology.The new species is named in honour of Herbert Zettel, prominent specialist on Oriental Gerromorpha and Nepomorpha, curator of Hemiptera at the NHMW, who made my studies in NHMW possible and helped me with loans of specimens during the last two decades.Collection circumstances.The habitat at the type locality, Balphakram National Park, is illustrated on Fig. 14.Distribution.India (Meghalaya) (Fig. 16).Description.Colour.Nearly unicolorous reddish brown, head, anterior disk of pronotum and sternum (except metepisternum) slightly darker than the rest of body, distifl agellum fuscous; basal part of posterior half of pronotum between the punctures whitish; basal part of scutellum brown; clavus and anterior part of corium indistinctly paler than the rest, second 2/5 of costal margin and three tiny, indistinct spots on apical half of corium pale; membrane translucent, small spots (streaks on veins and triangular spots on margin at end of veins) fuscous; legs stramineous; abdomen reddish brown, posterior third of connexival segments dorsally and ventrally pale.
Structure as in L. puskasi sp.nov.but anterior half of pronotum widest at transversal furrow (slightly narrower in medial portion of anterior pronotal lobe) (Fig. 5).No elevations on anterior half of pronotum; pronotal midline insignifi cant; basal quarter of pronotum sparsely punctate with large impunctate areas; lateral margin fi nely serrate.Mesosternum with very fi ne punctures only, medially not transversely wrinkled.Labium reaching end of mid coxae, segment I reaching base of head.Abdomen very fi nely and rather sparsely punctate, not wrinkled, shiny.Paramere slender with short sensory lobe (Fig. 12).
Measurements (in mm).Holotype (paratype), length of labium provided only for holotype.Body length 2.95 (2.82); head: length 0.45 (0.42), width 0.72 (0.70), interocular space 0.42 (0.42); pronotum: length 0.85 (0.82), width at base 1.42 (1.39); scutellum: length 0.65 (0.62), width 0.72 (0.70); claval commissure length 0.22 (0.24); length of antennal segments: scape 0.22 (0.22), pedicel 0.38 (0.38), basifl agellum 0.40 (0.38), distifl agellum 0.51 (0.50); length of labial segments: I 0.35, II 0.46, III 0.22, IV 0.26.Differential diagnosis.Latidrymus fl avus sp.nov. is the only species in the genus which has a rather unicolorous corium (without dark spot and basal half of it not paler than apical half).This is also the only species of the genus characterised by large impunctate areas on basal part of pronotum and where the pronotum is continuously tapering anteriad.The fi ne serration of the lateral margin of the anterior lobe of pronotum is the strongest in this species.It is different from L. elevatus sp.nov.and L. zetteli sp.nov. in lacking elevations on anterior half of pronotum and in insignifi cant pronotal midline.Etymology.The name of the new species is the Latin adjective fl avus (-a, -um), meaning yellow, referring to the coloration of its body.Collection circumstances.The specimens from Luang Namtha were collected in remnants of a primary forest, in small wet ravines along brooks (Fig. 13).Specimens from Ban Khoun Ngeun were collected in remnants of a (probably primary) lowland forest, near a large river (V.Kubáň, pers. comm.).Distribution.Northern and central Laos (Luang Namtha and Khammouane Provinces, respectively) (Fig. 13).Comment.There is a female from Sumatra (Fig. 16) deposited in NHMW which is rather similar to L. puskasi sp.nov.but larger than the known specimens (4.2 mm) and its colouration is paler.It could merely represent an intraspecifi c variety of L. puskasi sp.nov.but it more likely belongs to another species-group taxon, which cannot be determined in the absence of additional material.
Comment.There is another specimen, a male from China (Fig. 16) which is rather similar to the types of L. elevatus sp.nov.However, it is of darker colouration and its pronotum is of slightly different shape.Currently it is not possible to make a decision about its identity, therefore it is not included in the type material of L. elevatus sp.nov.