Aegus taurus Boileau, 1899

Cao, Yuyan, Webb, Michael D., Bai, Ming & Wan, Xia, 2016, New synonymies and records of the stag-beetle genus Aegus MacLeay from Chinese fauna (Coleoptera: Lucanidae), Zoological Systematics 41 (3), pp. 261-272 : 264-266

Aegus taurus Boileau, 1899 ( Figs 6–9 , 18 )

Aegus taurus Boileau, 1899 . Bull. Soc. Ent. Fr., 48: 320.

Aegus beauchenei Boileau, 1902a . Bull. Soc. Ent. Fr., 1902: 288. syn. nov.

Aegus caprinus Didier, 1928 . Librairie speciale Agricole, Paris Fascicule 2: 60. syn. nov.

Type material examined. Syntype ♂ of Aegus taurus Boileau ( MNHN), labelled: “Type [red color] / Type [yellow color] / Ht. Tonkin, N. O. De Bao-Lac, Dr. Battarel, 1897–1898 / ex. coll. Boileau / MUSEUM PARIS, Coll. Didier / taurus Boil. ” Syntype ♂ of Aegus taurus (BMNH) , labelled: “ Paratype (red label) / Ht. Tonkin, Dong Van, Cap Gadel 1898 / 7033 / H. E. Bomans BMNH (E) 1999-248” . Syntype ♂ of Aegus beauchenei Boileau ( MNHN), labelled: “ Type [red color] / Type [yellow color] / Tonkin, Montes Manson, April–Mai, 2000–3000 feet, H. Fruhstorfer / Museum Paris, ex. coll. R. Oberthür / Beauchesnei, Types ♂ ♀, H. Boileau / Aegus beauchenei, Boil. , Holotype ♂, J. P. LACROIX, det., 1974” . Syntype ♀ of Aegus beauchenei Boileau ( MNHN), labelled: “ Tonkin, Montes Manson , April–Mai, 2000–3000 feet, H. Fruhstorfer / Museum Paris, ex. coll. R. Oberthür / Aegus beauchenei, Boil. , allotype ♀, J. P. LACROIX, det., 1974” . Syntype ♂ of Aegus caprinus Didier ( MNHN), labelled: “ TYPE [red label] / TYPE [yellow lable] / nam mar, 6-14-1918 / MUSEUM PARIS, Coll. Didier, 1937 / A. caprinus, Did. , Holotype ♂, J. P. LACROIX, det., 1973” .

Additional material examined. China, Hainan, Jianfengling, Tianchi , 750 m, 22.III.1980, 3♂ 2♀, leg. Shuyong Wang ( NZMC) ; Guangxi, Longzhou, Mt. Daqingshan , 360 m, 22.I.1963, 1♂, leg. Chunguang Wang ( NZMC) ; Guangxi, Napo, Beidou , 550 m, 22. VI .2000, 1♀, leg. Jun Chen ( NZMC) ; Guangxi, Jinxiu, Mt. Dayaoshan , 25. VI .2011, 7♂ 2♀, leg. Xiaoyan Hu ( MAHU) .

Distribution. China (Guangxi, Hainan), N. Vietnam.

Remarks. Boileau (1899) described this species from many males from North Vietnam in the following way: “Plusieurs ♂, du Haut-Tonkin: Dong-Van”. It was described on the basis of typical large males but small males were also mentioned and the female was unknown. A large male (syntype) with “Type” and handwritten labels of Boileau in the MNHN has external characters consistent with the original description. A small male labelled “ Paratype ” in the BMNH from Bomans collection is also considered a syntype as its external characters and locality correspond to the original description.

The two species treated here as junior synonyms of A. taurus were described from the same area as A. taurus . The first A. beauchenei was described from many examples (syntypes) in the following way: “ Tonkin, plusieurs exemplaires”. A medium-sized male and a female with “Type” and handwritten labels of Boileau ( MNHN) are considered syntypes ( Figs 7, 9 ); “ beauchenei ” in the paper was wrongly written as “ Beauchesnei ” on the handwritten label ( Fig. 7b ). The second species, A. caprinus was described from an unknown number of males (small) and females (syntypes) in the following way: “Types ♂ et ♀ de Nam-Mia et Pow-Lan ( Tonkin) ex-collection Boileau”. A small male syntype ( Fig. 8 ) has been examined ( MNHN) but the female has not been found during this study.

Morphological comparisons of the above type specimens revealed that of all three species belong to the same species. All share the following stable characters: male mandibles with small, short and triangular ventral basal teeth; labrum laminated and gently curved; pronotum transverse with truncated front angles, median longitudinal depression present but with very sparse punctures; six deep dorsal striae and two weak lateral oblique striae on each elytron; the meso- and hind femora with dense yellow hairs ventrally. As a key character for species identification, the aedeagus of the three type specimens show several similarities: PA laminated, about 1/3 length of BP, apex sharp in the lateral view; BP quite long, almost parallel-sided in basal 2/3 and sharp in distal 1/3; ML almost symmetrical, with almost straight lateral margins and very small, sharp and incurved apex; PES stout, covered with densely hairs, about twice as long as length of tegmen ( Fig. 18 ). Therefore, we proposed A. beauchenei and A. caprinus as two new junior synonyms of A. taurus with the following intraspecific variation: syntype of A. taurus a large male, syntype of A. beauchenei a medium-sized male, syntype of A. caprinus a small male and a syntype of A. beauchenei a female.

Maes (1992) listed A. taurus as a subspecies of A. laevicollis without explanation. In fact, they are totally different species due to the morphology of the mandibles, labrum and pronotum ( Figs 1–9 ). The aedeagus is also distinctly different in the two species, especially the PES of A. taurus ( Fig. 18 ) which is short and very stout, while that of A. laevicollis ( Fig. 17 ) is quite long and thin.

Figures

Figures 6–9. Aegus taurus. 6. Syntype of A. taurus, large ♂. 7. A. beauchenei, syn. nov. of A. taurus, syntype, medium-sized ♂. 8. A. caprinus, syn. nov. of A. taurus, syntype, small ♂. 9. A. beauchenei, syn. nov. of A. taurus, syntype, ♀. a. Dorsal view. b. Labels. c. Ventral view. d. Diagnosed specimen, dorsal view. Scar bars=10mm.

Figures 17–19. Aedeagus. 17. Aegus laevicollis. 18. A. taurus. 19. A. kuangtungensis. a. Ventral view. b. Lateral view. Scar bars= 1 mm.

Figures 1–5. Aegus laevicollis. 1. Syntype of A. laevicollis, large ♂. 2. Medium-sized ♂. 3. Syntype of A. punctiger (synonym of A. laevicollis), ♀. 4. Syntypes of Aegus pichoni (synonym of A. laevicollis), small ♂. 5. Syntypes of Aegus pichoni (synonym of A. laevicollis), ♀. a. Dorsal view. b. Labels. c. Ventral view. Scar bars=10 mm.