Research Article |
Corresponding author: Guodong Ren ( gdren@hbu.edu.cn ) Academic editor: Wolfgang Schawaller
© 2019 Zhonghua Wei, Guodong Ren.
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:
Wei Z, Ren G (2019) Description of larva and pupa of Laena haigouica (Tenebrionidae, Laenini) from China based on morphology and four DNA makers. ZooKeys 852: 101-109. https://doi.org/10.3897/zookeys.852.32095
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The larvae, pupae, and adults of Laena haigouica Schawaller, 2001 were collected during recent fieldwork in the Sichuan Province (China). Since the pupal morphology of Laena has never been investigated this created an opportunity to provide the first description. Moreover, prior to this study larval characters of only one species, Laena starcki Reitter, 1887, were known. Therefore, description of the larva of L. haigouica enabled the first verification of the intrageneric stability of larval characters revealed for other Laena species. Association of the studied immature stages with the adults was confirmed by analysing COI sequences. Additionally, three other loci (16S, Cytb, 28S) were sequenced for L. haigouica during this study.
DNA markers, Laena, larva, pupa, darkling beetle, systematics
The genus Laena contains approximately 261 species in Palaearctic region (
Recently, the larvae, pupae, and adults of Laena haigouica Schawaller, 2001 were collected during fieldwork in damp deadwood in Sichuan Province of China. Therefore we speculated that the larvae of L. haigouica were feeding on deadwood or fungi. The larva and pupa are described, photographed, and figured for the first time in this paper.
Larvae, pupae and adults of Laena haigouica were collected on 27 July 2016 from Zhongcha rangeland, alt. 2870 m, Jiuzhaigou County (Sichuan Province, China) by Xiumin Li, Xinglong Bai, Xianlei Shao and Runyang Zhang. All examined specimens were preserved in 70% alcohol and deposited in the Museum of Hebei University, Baoding, China.
Larvae were observed and described using Nikon SMZ800. Photographs of larvae and pupae were taken with a desktop SEM Hitachi TM3000 and Leica M205A stereomicroscope equipped with a drawing tube, and a Leica DFC450 camera.
Total genomic DNA was extracted from larval, pupal, and adult tissue using EZNA Insect DNA Kit (Omega Bio-tek, USA), following manufacturer’s protocols. One fragment of the mitochondrial protein-coding gene (COI) was amplified respectively from larva, pupa, and an adult; one fragment of the mitochondrial protein-coding gene (Cytb) was amplified from an adult; one fragment of the mitochondrial ribosomal RNA gene (16S) was amplified from an adult; and one fragment of nuclear rRNA gene (28S) was amplified from an adult. The detailed methods of the molecular studies are the same as those used in
Laena haigouica Schawaller, 2001: 19–20, figs 41–44. Type locality: China, Sichuan, Jiuzhaigou.
Larvae (11 ex), pupae (2 ex), adults (4♂7♀), Sichuan, Jiuzhaigou, Zhongcha rangeland, 2870 m, 27.VII.2016, Xiumin Li, Xinglong Bai, Xianlei Shao & Runyang Zhang leg., HBUM.
Diagnosis. The larva of L. haigouica Schawaller, 2001 can be separated from L. starcki Reitter, 1887 by following characters: clypeus transverse, 3.3 times wider than long, surface with four long erect setae; abdominal spiracles on lateral margins of tergites III–VIII in middle or just before middle.
Description.
The description is based on what is probably a later instar larva. Body length 15–17 mm. Body (Fig.
Head.
(Fig.
Thorax. Thoracic tergites light yellow. Prothoracic tergum subquadrate, longer than wide, 1.4–1.5 times as long as meso- or metatergites; surface with short and long erect setae. Meso- and metatergites wider than long; surface with short and long erect setae. Spiracles oval; prothoracic and metathoracic without spiracle; mesothoracic spiracles on anterolateral part, largest, approximately twice size of abdominal spiracles. Metathoracic tergum distinctly wider than pro- and mesothoracic tergum. Coxal cavity distinctly separate.
Abdomen.
Abdominal tergites light brown, slightly darker than sternites; surface smooth, with short and long erect setae. Abdominal tergites I–VIII wider than long, widest in middle; lateral margins of abdominal tergites curved. Abdominal tergite IX distinctly narrower than tergite VIII; anterior margin distinctly wider than posterior margin; tergite IX posteriorly round, armed with pair of acute urogomphi (Fig.
Legs.
Surface with long erect setae; proleg (Fig.
Larval morphology of Laena haigouica Schawaller, 2001 A–B head, in dorsal and ventral views C mouth and appendages, in ventral view D antenna, in lateral view E apex of maxillary palpus F segments IX, in dorsal view G–I pro-, meso- and metalegs, in ventral view J–K urogomphi in ventral and lateral views.
Diagnosis.
Compared to the known pupa of Lagria villosa described by
Description.
Body length 10.5–11.2 mm, body width 2.5–2.9 mm; body white to light brown (Fig.
Head. Dorsal surface smooth, concealed (invisible in dorsal view). Anterior margin of labrum rounded, with sparse short setae. Clypeus with two long erect setae on each anterolateral side. Frons and vertex with sparse granules bearing long erect setae. Eye ovate, black. Mandible apices brown. Antenna long and thick; antennomeres IV–XI with small brown spots on apex in dorsal view, without setae.
Thorax. Pronotum transverse. Anterior margin straight, with eight granules bearing long erect setae; anterior angles subrectangular, posterior angles rounded; lateral margins curved, each side with seven granules bearing long erect setae. Disc surface convex, with sparse granules bearing long erect setae. Mesonotum and metanotum distinctly narrower than pronotum, each with four setae posteriorly. Mesoventrite, metaventrite and elytra glabrous.
Abdomen.
Abdominal spiracles ovate. Tergites I–VIII each with four pairs of setae (Fig.
Legs. Prolegs distinctly longer than meso- and metalegs. Femora covered with sparse erect setae. Tibiae and tarsi glabrous, without setae.
Comment. These two specimens probably represent early stage pupa, which have the body colour light and antenna and tarsi near translucent.
The morphological characteristics of larvae of subfamily Lagriinae were summarized by
The description provided above for L. haigouica is the first contribution to the knowledge on the pupal stages of Laenini. Pupa possess lateral processes which were considered to be plesiomorphic among the whole Tenebrionidae (
We are grateful to Xiumin Li and Xinglong Bai for their collaboration in field work in Sichuan. We also thank Dr. Marcin Kamiński and anonymous reviewer for their valuable suggestions. This work was supported by the National Natural Science Foundation of China under Grant No. 31572309, the Ministry of Science and Technology of the People’s Republic of China under Grant No. 2015FY210300.