Aegus acuminatus (Fabricius, 1801)

(Figs. 12–14, 17, 21, 27–28, 33)

Lucanus acuminatus Fabricius, 1801: 251 . Type locality: Sumatra. Schönherr 1817: 325; Hope 1837: 78; Hope & Westwood 1845: 6.

Lucanus cornutus Thunberg, 1806: 169 . Type locality: Java, Sumatra, Indie Orientali. Schönherr 1817: 325 (as synonym).

Aegus obscurus Macleay, 1819: 113 . Type locality: not specified. Burmeister 1847: 399 (as synonym).

Dorcus acuminatus: Dejean 1836: 194; Burmeister 1847: 399.

Aegus acuminatus: Burmeister 1847: 399; Reiche 1853: 82; Lacordaire 1855: 30; Thomson 1862: 399; Parry 1864: 91; Parry 1870: 93; Gestro 1881: 331; Van Roon 1910: 40; Benesh 1960: 98; Bomans 1974: 178; Maes 1990: 17; Bomans 1991: 293; Mizunuma & Nagai 1994: 281; Krajcik 2003: 8; Fujita 2010: 319.

Aegus ogivus Deyrolle, 1865: 33, pl. II, fig. 5. Type locality: Malacca, Peninsula. Parry 1870: 54; Gestro 1881: 331; Van Roon 1910: 42; Bomans 1991: 300 (as synonym); Hutacharoen 2011: 247.

Aegus splendidus Nagel, 1928: 288 . Type locality: Borneo. Bomans & Benoit 2007: 7 (as synonym).

Aegus machimus Didier & Séguy, 1953: 104 . Type locality: Medan, Sumatra. Bomans 1991: 300 (as synonym).

Aegus bawangensis Nagai, 1994: 32, pl. 118, fig. 501. Type locality: Mt. Bawang, SW Kalimantan. Bomans & Benoit 2007: 7 (as synonym); Fujita 2010: 321.

Aegus acuminatus simeuluensis Nagai, 1994: 32, pl. 118, fig. 502 (37–39). Type locality: Simeulue Is., Indonesia. Bomans & Benoit 2007: 27 (as synonym); Fujita 2010: 320.

Aegus acuminatus niasicus Nagai, 1994: 32, pl. 118, fig. 502 (40–41). Type locality: Nias Is., Indonesia. Bomans & Benoit 2007: 27 (as synonym); Fujita 2010: 320.

Aegus acuminatus natuensis Nagai, 1994: 33, pl. 118, fig. 502 (42–44). Type locality: Natuna Is., Indonesia. Bomans & Benoit 2007:27 (as synonym); Fujita 2010: 320.

Aegus suzumurai Nagai, 1994: 32, pl. 118, fig. 500 (1–2). Type locality: Natuna Is., Indonesia. Bomans & Benoit 2007:61 (as synonym); Fujita 2010: 330.

Material examined (10♂♂, 6♀♀). Thailand: 1♂ (WPC), Surat Thani Prov., Khao Sok, 10.I.2020, W. Pathomwattananurak leg. ; 5♂♂, 3♀♀ (WPC), Nakhon Si Thammarat Prov., Thung Song Dist., Nam Tok, 15.XII.2021, Aussawa Samudjit leg. ; 1♂ (WPC), Trang Prov., Huai Yod Dist., 2.XII.2018, Aussawa Samudjit leg. ; 2♂♂, 1♀ (WPC), Trang Prov., Huai Yod Dist., 16.V.2018, Aussawa Samudjit leg. ; 2♀♀ (WPC), Trang Prov., Huai Yod Dist., I.2021, Aussawa Samudjit leg. ; 1♂ (RBMF), Prachuap Khiri Khan Prov., Pran Buri Dist., Khaojao Subdist., 27.I.2021, K. Jiaranaisakul leg.

Distribution. Indonesia, Malaysia and Thailand (Satun, Trang, Nakhon Si Thammarat, Phuket, Surat Thani and Prachuap Khiri Khan Provinces) (Mizunuma & Nagai 1994; Krajcik 2003; Fujita 2010; Hutacharoen 2011).

Remarks. The species was already recorded from Thailand under the name Aegus ogivus Deyrolle, 1865 by Hutacharern (2011). We reconfirm its distribution in Thailand and give the northernmost distribution record of this species (Fig. 51).