A new genus record and species of Dromoceryx Schmidt-Goebel, 1846 (Coleoptera, Carabidae, Lebiini) from Taiwan, with a revised key to species.

We describe a new genus record for Taiwan and a new species of the genus Dromoceryx Schmidt-Goebel, 1846. We add to the known fauna and distribution of the genus with a description, habitus, genitalic images, as well as a geographic range map for Dromoceryxnigrofovealis sp. n. A revised key to all species of the genus is included.


Introduction
Until a thorough revision of this genus by Mateu (1984) in French, Dromoceryx was considered by many (Atkinson 1890;Bates 1892;Andrewes 1923) to be a likely synonym of Metabletus Schmidt-Goebel, 1846. Mateu treated the three known species and cited the structure of the mentum (with a median tooth), glossal sclerite, unique elytral macula pattern, and genitalic form of both male and female as characteristics that define Dromoceryx as a genus. Other than an apparent South (India) and South-east (Vietnam) Asian distribution, little else is known about the natural history of this group. Here, we describe a new species of the genus Dromoceryx based on the examination of several specimens recently collected in Taiwan.

Material
This work is based on the study of 36 specimens. Adult specimens were collected by or borrowed from various institutions listed below, along with a four-letter coden used to identify sources of specimens (Arnett et al. 1993). The names of the curators of these collections appear in parentheses below.

Fieldwork.
We first encountered this species when Yen-Chiu Lan (University of Kang Ning, Tainan) provided specimens collected from her 2010 faunistic study on the insects of Kenting National Park, Pingtung County, Taiwan. Our examination of this material indicated that it was both a new genus record for Taiwan and a new species for the genus Dromoceryx. After scouring other museums for specimens of this species, it was clear that little was known about the habitat preferences or biology of Dromoceryx species other than that they readily came to ultraviolet light and light traps. Because of this, we were eager to locate more individuals in the field. Adults of this species had also been previously collected from the Liouguei Research Center of southern Taiwan. In April of 2014, Yi-Ming Weng, Dash Hwang, and Wesley Hunting, went there for several days to try and locate this seemingly uncommon insect species. During that time we were able to collect three individuals, two specimens from a mercury vapour light sheet and one in mixed primary forest on deadwood. Preparation and examination of adults. Standard methods were used for mounting, dissecting, and preparing genitalia, among other technical procedures (Ball and Hilchie 1983;Frania and Ball 2007). Genitalia and other small structures were preserved in glycerine and stored in microvials that were pinned beneath the specimen from which they had been removed.
Images and illustrations. A photograph of species habitus ( Fig. 1) was taken using a Nikon D7100 fitted with an AF-S VR Micro-NIKKOR 105mm f/2.8G IF-ED lens and mounted on a copy stand. Photographs of genitalia ( Fig. 2a-d) were taken with a Nikon D7100 mounted on a Olympus SZX16 trinocular stereoscopic microscope and layered together using Zerene Stacker (Zerene Systems LLC, Richland, WA). A line drawing of the female genital tract (Fig. 3) was prepared by taking photographs with a Nikon D7100 and then importing them into Adobe Illustrator 11.0 (Adobe Systems, Inc., Mountainview, CA). Plates were also prepared using Adobe Illustrator 11.0.
The Geographic range map was prepared using a modified map from Ginkgo Maps (http://www.ginkgomaps.com); projection used is NAD Lambert Conformal Conic, 1983.
Measurements. Measurements were made at 25× with a Wild M5 stereoscopic microscope fitted with an ocular micrometer. Various measurements are expressed in the text by abbreviations, as used by Ball and Shpeley (2005) and Hunting (2013):

HL
Length of head, measured on left side, from base of left mandible to posterior margin of compound eye.

HW
Width of head, maximum transverse distance across head, including eyes.

PL
Length of pronotum along midline. PWM Maximum width of pronotum.

EL
Length of elytra from basal ridge to apex.

EW
Maximum width of elytra.

OBL
Overall body length.
The shape of the head and pronotum is shown by the ratio of the width over length (HW/HL; PWM/PL, ML/MW), and elytral shape is indicated by the ratio of the length to the width (EL/EW).
To indicate the range of body size of each species, the overall body length (OBL) was measured from the apex of the extended mandibles to the apex of the elytra of both the largest and smallest individuals of each species (Frania and Ball 2007).
The size of male genitalia was determined by drawing a straight line between the apical area and the basal lobe of the phallus. The size of female genitalia was determined by drawing a straight line across the outside margin of widest portion of left lateral tergite to outside margin of widest portion of right lateral tergite. Taxonomic note. The type of D. dorsalis is in the National Museum of Natural History (NMPC), Prague, Czech Republic. According to Andrewes (1923) and Mateu (1984), it is a single specimen with no antennae or palpi and is in otherwise poor condition.

Systematic zoology
Recognition. This genus is distinguished from others by the following combination of characters: Broad and somewhat flattened body. Small size: 3.5-4.5 mm. Glossal sclerite broad, with narrow latero-apical lobes, four setae visible at apex, two longer seta more laterally and two shorter setae more medially. Mentum with single shallow tooth. Head and pronotum brunneous to piceous, elytral disc testaceous with black macula. Gonocoxite 2 slightly spatulate, broadly rounded at apex; two lateral ensiform setae, one on each side, seta-like as opposed to spine-like, two nematiform setae. For a detailed account and figures of the male and female genitalia of the already described species of Dromoceryx, see Mateu (1984). Elytra with foveae of umbilical setae piceous (Fig. 1). Disc of pronotum brunneo-piceous to piceous. Taiwan  Diagnosis. This species is readily distinguished from other Dromoceryx species by the combination of: head and pronotum piceous to black and lateral margins with foveae of umbilical setae piceous. Individuals of this species also have an elytral macula pattern that is less variable when compared to specimens of D. dorsalis (Mateu 1984).
Macrosculpture and pilosity. Dorsum of head smooth, with a few very fine punctures, hardly visible at 50×. Pronotum smooth, with very fine, randomly scattered setigerous punctures, hardly visible at 50×; elytral intervals with ± single row of very fine, setigerous punctures along length, hardly visible at 50×; stria with few faint punctations, setae not visible at 50×; ventral surface with very fine, randomly scattered setigerous punctures.
Fixed setae. Two pairs of supraorbital setae; clypeus with two lateral setae; labrum with six setae along apical margin; pronotum with two setae along each margin, one at base of lateral margin and one on lateral margin at pronotum maximal width; elytra with two setae in interval 3, one seta just before mid-length, one seta in apical 1/3 rd ; 11-12 lateral (umbilical) setae in interval 9; two setae on each of abdominal sterna III to VI; two setae along apical margin of sternum VII in males, females with four setae near apical margin of sternum VII, medially setae much shorter and finer than outer setae.
Head. Mandibles short, with wide base; labrum wider than long, rectangular; mentum with shallow tooth; eyes somewhat convex.
Pronotum. Anterior transverse impression very shallow; posterior transverse impression very shallow; median longitudinal impression moderately shallow; disc moderately flat, basal angles obtuse, lateral margins broadly rounded, margins narrow.
Male genitalia. Fig. 2A-D. Length 0.84-0.92 mm. Ostium catopic, long, slightly more to left side in ventral view; phallus cylindrical, left side narrowing from mid-length to apex, right side relatively straight in ventral view, apex narrow, rounded, sharply pointed in lateral view; endophallus short and wide, several patches with microtrichia slightly enlarged and more sclerotized than remaining surface, visible in non-everted specimens.
Habitat, habits and seasonal occurrence. The known elevational range of D. nigrofovealis is from 240 to 670 m. Adults of this species live in mixed primary and secondary forests. Adults are crepuscular or nocturnal and readily come to light. All known specimens have been collected from February to May. Collecting methods include ultraviolet light, mercury vapour light sheet, incandescent light, and hand collecting.
Geographical distribution. To date, this species is known from a few localities in the southern third portion of Taiwan (Fig. 4).