Research Article |
Corresponding author: Zhen Liu ( qingniao8.27@163.com ) Corresponding author: Shi-hong Jiang ( sjiang@szpt.edu.cn ) Academic editor: Hume Douglas
© 2019 Zhen Liu, Shi-hong Jiang.
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:
Liu Z, Jiang S-h (2019) The genus Scutellathous Kishii, 1955 (Coleoptera, Elateridae, Dendrometrinae) in China, with description of three new species. ZooKeys 857: 85-104. https://doi.org/10.3897/zookeys.857.29011
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Five species of Scutellathous Kishii, 1955 are recognized from China, of which three are new. Scutellathous habenularis sp. nov., S. nanlingensis sp. nov., and S. quadrata sp. nov. are described and illustrated. A key to species from China, a checklist, and a distribution map are provided. The relationships and comparisons among genera Athous Eschscholtz, 1829, Ohirathous Han & Park, 2012, Parathous Fleutiaux, 1918, and Scutellathous Kishii, 1955 are discussed.
Athous, catalogue, distribution, Elateroidea, key, new taxa, Ohirathous
The genus Scutellathous (Coleoptera, Elateridae), as currently defined, is distributed only in East Asia: China (Taiwan), Japan, and Korea. It was erected by
Scutellathous includes mid-sized beetles (body length: 11–16 mm), resembling the monotypic genus Ohirathous Han & Park, 2012 in sharing similar shaped frons (supra-antennal carina thickened, overhanging nasale, raised above part of frons immediately posterior to it, (‘pentroof shape’, sensu
During our study of the Chinese elaterids, we found three undescribed species from south China. These new species resemble monotypic genus Ohirathous Han & Park, 2012 in sharing the ‘pentroof’ shape of frons and broad sublateral incisions (
The studied specimens are deposited in the following collections:
MHBU Museum of Hebei University, Baoding, China.
The terminology used mainly follows
Measurements: body length was measured along the midline from the anterior edge of the head capsule to the apex of the elytra; the body width was measured across the broadest part (usually across the elytra). The pronotal length was measured along the midline; the pronotal width was measured at the broadest part (usually at the hind angles). The ocular index is obtained by dividing the minimum distance between the eyes by the maximum distance across both eyes and multiplying the quotient by 100 (
The specimens were mounted on paper points. The genitalia were removed, cleaned and fixed under the body of the specimen in glycerol mounts as described by
The studied specimens were all collected by hand netting.
Scutellathous
Kishii, 1955: 79 (type species: Athous comes Lewis, 1894: 200 (Sapporo, Japan; by original designation);
Body length: 11–16 mm; frons triangularly depressed behind supra antennal carina, which is strongly thickened and overhanging labrum and nasale, carina elevated above part of frons immediately posterior to it in dorsal view; supra-orbital groove broadly excavated; antennae serrate from 3rd antennomere; pronotum mostly longer than wide, pronotal disc with weak median depression; hind angles of pronotum unicarinate; sublateral incisions at posterior margin of pronotum small, or tooth-like; prosternal sutures not grooved anteriorly; apical end of tarsomeres 2 and 3 lobed beneath; aedeagus with simple and narrow parameres apices, without apico-lateral expansion at apex, penis gradually narrowed and acute at apex (after
China, Japan, and Korea.
Based on a study of the descriptions and photos of Athous (Elateridae, Dendrometrinae) species from North America, we found the Athous cucullatus (Say, 1825) species-group shares many characters with Scutellathous (Becker, 1979). These include head flattened with triangular depression; frontal carina prominent, well elevated above labrum; eyes large; punctures on pronotum umbillicate; tarsomeres 2- and 3-lobed; and male genitalia with parameres lacking subapical lateral tooth and dorsal carina. However, lobes on tarsomeres 2 and 3 are smaller in Scutellathous, the carinae on the pronotal hind angles are present and sharp in all Scutellathous (absent or present in A. cucullatus group), and base of pronotum with sublateral incisions near hind angles in all Scutellathous (some without incisions in A. cucullatus group). Further comparison of members of the North American Athous cucullatus species group to Ohirathous is needed.
1 | Pronotum with a median furrow (Fig. |
2 |
– | Pronotum with a median furrow only on posterior half, never with non-furrowed glabrous line | 4 |
2 | Aedeagus with penis reaching beyond parameres (Fig. |
S. nanlingensis sp. nov. |
– | Penis reaching only to apex of parameres (Figs |
3 |
3 | More pubescent, dorsal pubescence partially hiding integument (Fig. |
S. quadrata sp. nov. |
– | Less pubescent and more shiny (Fig. |
S. habenularis sp. nov. |
4 | Elytra with a short spine near humeral angles in dorsal view; antenna falling short of pronotal hind angle apex by length of the last antennomere; hind angles not divergent posterad | S. spinosus Platia & Schimmel, 2007 |
– | Elytra without spine near humeral angles; antenna longer, exceeding apex of hind angle of pronotum by at least length of two antennomeres; hind angles divergent | S. yamashitai Arimoto, 1992 |
Scutellathous habenularis sp. nov. [China (Yunnan)]
Scutellathous nanlingensis sp. nov. [China (Guangdong)]
Scutellathous quadrata sp. nov. [China (Zhejiang)]
Scutellathous spinosus Platia & Schimmel, 2007 [China (Taiwan)]
Scutellathous yamashitai Arimoto, 1992 [China (Taiwan)]
Yunnan, China.
Holotype: ♂ (MHBU), labels: 1) Yunnan Prov., Gaoligong Mts (2000 m, 25°59'8.81"N 98°49'1.40"E) (高黎贡山), 2012.VII.23, leg. Ji-shan Xu et Ling-xiao Chang, Shenzhen Polytechnic; 2) Holotype, Scutellathous habenularis sp. nov., Liu et al. 2019; 3) No. 20180353. Paratype: 1♀ (MHBU), labels: 1) Yunnan Prov., Gaoligong Mts (2000 m, 25°59'8.81"N 98°49'1.40"E) (高黎贡山), 2012.VII.23, leg. Ji-shan Xu et Ling-xiao Chang, Shenzhen Polytechnic; 2) Paratype, Scutellathous habenularis sp.nov., Liu et al. 2019; 3) No. 20180354.
Body bright red-brown, shiny; anterior edge of head truncate in dorsal view; antennae reaching apices of pronotal hind angles, nearly cylindrical from antennomere 6 onward, attached apico-dorsally, antennomere 3 1.8 times as long as 2 and nearly as long as 4; pronotum with hind angles divergent posterad, disc flat medially with only trace of a glabrous non-furrowed longitudinal line, shiny with umbillicate punctures; scutellar shield 1.1 times longer than wide; aedeagus with penis reaching to apex of parameres, penis gradually narrowed to pointed apex.
Scutellathous habenularis is similar to S. yamashitai
Male (holotype). Body (Fig.
Head. Anterior edge truncate in dorsal view (Fig.
Thorax. Pronotum (Fig.
Scutellar shield. 1.1 times longer than wide (Fig.
Elytra. Slender (Fig.
Legs. Slender (Fig.
Abdomen. Surfaces of sternites III–VII like metaventrite, with punctures and pubescence more regular and evenly distributed laterally; sternite VII (Fig.
Genitalia. Aedeagus (Fig.
Female. Like male (Fig.
Larva. Unknown.
The name of the new species is derived from the Latin “habenularis” (Latin for “strip”) referring to its hind coxae abruptly and strongly narrowed into a strip at lateral one-fourth part.
China: Yunnan (Fig.
Collected around the elevation of 2000 m in subtropical evergreen forest.
Its bursa copulatrix resembles Ohirathous in sharing a circular thorny line, but differs in lacking thorny plates. Other characters (carina on hind angles extending only basal 1/5 of pronotal length; antennomere 3 2.1 times as long as 2; shape of male genitalia; shape of female pronotum; only tarsomeres 2 and 3 lobed beneath) are consistent with the diagnosis of genus Scutellathous. Structures of the bursa copulatrix are diverse within Scutellathous species – from five thorny plates (S. comes, S. porrecticollis, S. sasajii, S. shikokuanus) or four (S. seinoi) thorny plates and without thorny line to no thorny plates but with thorny line in S. habenularis. The bursa copulatrix structure of Ohirathous (a circular thorny line and two thorny plates) falls within the range of variation observed in Scutellathous and does not support distinction of Ohirathous from Scutellathous. Unfortunately, male genitalia of Ohirathous is unknown. Further phylogenetic study is needed to understand the monophyly of Ohirathous and the relationship between these two genera.
Ruyuan Nanling Mts, Guangdong, China.
Holotype: ♂ (
Antennae barely reaching apices of pronotal hind angles, antennomere 3 2.2 times longer than 2 and 1.1 times longer than 4; pronotum with narrow median furrow throughout length, shiny with fine, weakly umbillicate punctures; scutellar shield 1.5 times longer than wide; punctures on elytra becoming absent near apex; aedeagus with penis reaching beyond parameres, gradually narrowing to obtuse apex.
Scutellathous nanlingensis is similar to S. sasajii Kishii, 2001, but can be separated from the latter by the short antennae of male (hardly or just reaching apices of pronotal hind angles; longer in S. sasajii, with apical three antennomeres exceeding apices of the hind angles), with narrow median furrow through the length of the pronotum (in S. sasajii the pronotum lacks longitudinal furrow), and the longer male penis.
Male (holotype). Body (Fig.
Head. Anterior edge truncate in dorsal view (Fig.
Thorax. Pronotum (Fig.
Scutellar shield. (Fig.
Elytra. Slender, 2.8 times longer than wide, 2.8 times longer and 1.2 times wider than prothorax, longitudinally oviform, shiny, anterior half nearly parallel-sided, narrowing to apex from midlength, widest at apical third, with deeply-punctate striae, strial punctures elongate, the interpuncture spaces about 1–2 puncture diameters wide (Fig.
Legs. Slender (Fig.
Abdomen. Surface (Fig.
Genitalia. Aedeagus (Fig.
Female. Unknown.
Larva. Unknown.
The new species named after Nanling Mts in Guangdong prov., referring to its only known locality.
China: Guangdong (Nanling Mts) (Fig.
Unknown.
Genitalia of this specimen is shrunken, membranous parameres apices are folded in (Fig.
Scutellathous nanlingensis sp. nov., holotype, male a head, antero-dorsal view b pronotum, dorsal view c prothorax, ventral view d prothorax, lateral view e middle leg, dorso-lateral view f scutellar shield, dorsal view g hind coxae, ventral view h surface of elytra, dorsal view i surface of pronotum, dorsal view j antenna, lateral view.
Tianmu (Qianmutian) Mountains, Zhejiang, China.
Holotype: ♂ (
Body brown-black, dorsal pubescence partially hiding integument; anterior edge of head arched anterior-laterally in dorsal view; antennae reaching apices of pronotal hind angles, antennomere attached apico-dorsally near base, more centrally near apex, antennomere 3 2.2 times longer than 2 and 1.1 times longer than 4; pronotum with hind angles convergent posterad, disc with median non-furrowed glabrous line, with simple punctures; scutellar shield as wide as long, anterior edge straight, widest and rounded posteriorly, concave at sides.
Scutellathous quadrata is similar to S. spinosus Platia & Schimmel, 2007 (see Schimmel 2007) in body shape and size, but can be separated from the latter by the square-shaped scutellar shield (in S. spinosus it is 1.2 times longer than wide, measured from original figure), base without spine near humeral angles of the elytra (with spine in S. spinosus), the wholly brown-black body (in S. spinosus the body is entirely ferruginous), and the shape of parameres.
Male (holotype). Body (Fig.
Head. Anterior edge arched anterior-laterally in dorsal view (Fig.
Thorax. Pronotum (Fig.
Scutellar shield. (Fig.
Elytra. Together 2.4 times longer than wide (Fig.
Legs. Tarsomere 3 with a longer lobe than tarsomere 2 (Fig.
Abdomen. Surface of sternites III–VII like metaventrite, with punctures moreregular and dense and recumbent pubescence, interspaces with satin-like metallic sheen (Fig.
Genitalia. Aedeagus (Fig.
Female. Unknown.
Variability. Body length 14.7–15.7 mm; body width 3.7–4.3 mm.
Larva. Unknown.
The name of the new species refers to its quadrate scutellar shield.
China: Zhejiang (Tianmu Mts) (Fig.
Unknown.
Unfortunately, aedeagi of both specimens were damaged by poor preservation after prior dissection.
Scutellathous spinosus Platia & Schimmel, 2007: 59.
Following
Distinguished from other Scutellathous in China by elytral spine and red-brown colour. Distinguished from S. yamashitai by the shorter antennae not reaching the apices of the hind angles of the pronotum and rounded pronotal anterior angles.
No additions to the male genitalia except the length (1.75 mm) in original description. But we can see from the original image that the penis is reaching a little beyond the apex of the parameres, gradually narrowed to a pointed apex and the parameres are thick, strongly sinuate laterally at midlength, weakly tapered to a blunt apex.
China (Taiwan) (Fig.
Scutellathous yamashitai Arimoto, 1992: 73.
(after
Scutellathous yamashitai is similar to S. comes from Japan, but distinguished from by its darker color, smaller pronotal punctures, and divergent pronotal hind angles (
No specimen was available for this study.
China (Taiwan) (Fig.
We thank Dr. Kôichi Arimoto (Kyushu University, Japan), Dr. Pu Tang (Zhejiang University, China), Dr. Hume Douglas (Agriculture and Agri-Food Canada, Canada) and Prof. Alexander S. Prosvirov (Moscow State University, Russia) for their extensive comments on the manuscript. We are grateful to the collectors for their collecting efforts in the field, and to Prof. Guo-dong Ren (MHBU) for providing specimens for this study. Funding for this study was provided by the National Natural Science Foundation of China (31372231, 31772511) and scientific research project of