Research Article |
Corresponding author: Wesley Hunting ( hunting@ualberta.ca ) Academic editor: Achille Casale
© 2018 Wesley Hunting, Man-Miao Yang.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Hunting W, Yang M-M (2018) A new genus record and species of Dromoceryx Schmidt-Goebel, 1846 (Coleoptera, Carabidae, Lebiini) from Taiwan, with a revised key to species. ZooKeys 803: 121-130. https://doi.org/10.3897/zookeys.803.29737
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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 Dromoceryx nigrofovealis sp. n. A revised key to all species of the genus is included.
Carabidae , Dromiina , Lebiini , new species, new record, Taiwan
Until a thorough revision of this genus by
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 (
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 (
Images and illustrations. A photograph of species habitus (Fig.
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
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.
ML Metepisternum length.
MW Metepisternum width.
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 (
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.
Dromoceryx dorsalis Schmidt-Goebel, 1846: 40–41.
The type of D. dorsalis is in the National Museum of Natural History (NMPC), Prague, Czech Republic. According to
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
1 | Relatively large (4.4–4.5 mm). Elytral disc rufous to red, macula in apical portion of elytra, not contacted to apical third of elytral suture. India, Chennai (Madras) | D. magnus Mateu |
– | Smaller, < 4.1 mm. Elytral disc testaceous, macula covering, at least, basal two-thirds of elytral suture. India and elsewhere | 2 |
2 | Overall body length 3.0–3.2 mm. Elytra disc with isodiametric sculpticells. India, Chennai (Madras) | D. flavocircumdatus Mateu |
– | Overall body length > 3.4 mm. Elytra disc with transverse sculpticells | 3 |
3 | Elytra with foveae of umbilical setae piceous (Fig. |
D. nigrofovealis sp. n. |
– | Elytra with foveae of umbilical setae testaceous. Disc of pronotum brunneous. India,Vietnam | D. dorsalis Schmidt-Goebel |
The name of this species refers to the foveae of the lateral umbilical seta, which is piceous to black.
HOLOTYPE, male, labeled: “TAIWAN: Kaohshiung City / Maolin dist., Chung-Shin vill. / Liouguei Research Center / 22.9709N, 120.6822E”; “m.v. light sheet / 670m, Acc. Ti-209a / April 14, 2014, Y. Weng / D. Hwang & W. Hunting” [
Maolin District, Kaohshiung City, Taiwan.
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 (
OBL 3.52–4.08 mm. Length (n = 10 males, 10 females): head 0.32–0.44, pronotum 0.60–0.72, elytra 2.10–2.42, metepisternum 0.56–0.60 mm; width of head 0.82–0.96, of pronotum 1.04–1.20, of elytra 1.66–1.92, of metepisternum 0.32–0.40 mm.
Body proportions.HW/HL 2.10–2.56; PWM/PL 1.63–1.77; EL/EW 1.25–1.33; ML/MW 1.50–1.75 mm.
Color. Fig.
Microsculpture. Dorsum of head with mesh pattern isodiametric to slightly stretched longitudinally; pronotum with microsculpture almost isodiametric medially to somewhat transverse laterally, cells 1.5–2× wider that long; elytra with sculpticells transverse; ventral surfaces with microsculpture transverse.
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 1/3rd; 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.
Luster. Dorsum of head and pronotum moderately dull; elytra moderately glossy; ventral surface moderately glossy.
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.
Elytra. Intervals moderately flat, striae moderately impressed; elytral apices truncate.
Hind wings. Macropterous.
Legs. Claws pectinate, 4 or 5 denticles per claw. Male protarsi with adhesive vestiture ventrally, two rows of squamo-setae on tarsomeres 1–3 of fore-leg.
Male genitalia. Fig.
Female genitalia. Fig.
Line drawing of the female reproductive tract of Dromoceryx nigrofovealis, new species. Legend: bc bursa copulatrix; co common oviduct; gc1 gonocoxite 1; gc2 gonocoxite 2; les lateral ensiform setae; lt lateral tergite; ns nematiform setae; sg spermathecal gland; sgd spermathecal gland duct; sp spermatheca. Scale bar: 0.5 mm.
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.
We express our appreciation to all of the curators from the museums listed in the Materials and methods. Further, Wes Hunting thanks his friends and collecting companions, Yi-Ming Weng and Dash Hwang, for their help in collecting specimens in the field, as well as Yen-Chiu Lan (University of Kang Ning, Tainan) for providing specimens from her study on insects of Kenting National Park (project no. 513-99-02, 525-102-01-528, 525-104-01). Lastly, we thank everyone in the Yang lab for their support.