Heterometrus laoticus Couzijn, 1981

Kawai, Kazusa, Unnahachote, Thornthan, Suttisatid, Yossaphon & Tang, Victoria, 2023, А Review of Heterometrus in Thailand (Scorpiones: Scorpionidae), Euscorpius 373, pp. 1-25 : 15

Heterometrus laoticus Couzijn, 1981

( Figures 10–11 , 18–19 , 26–27 , 36–37 , 46–47 , 56–57 , 72–75 ) http://zoobank.org/urn:lsid:zoobank.org:act:36ECBBCC-

A638-4D5E-AA78-6B9AAC2F626F

Heterometrus laoticus Couzijn, 1981: 94 (part); Prendini & Loria, 2020: 245–252 , figs. 7F, 8F, 10, 24A, B, 38A, B, 51A–D, 70A, 71A, 72A, 157, 169–173, table 2 (reference list until 2020).

TYPE LOCALITY AND TYPE DEPOSITORY. Laos, Neïs ; MNHN RS 0030 .

MATERIAL EXAMINED. Thailand, Lamphun Province, Mae Tha District , May 2019, 1♂ 1♀, TUPC .

DIAGNOSIS (modified from Kovařík, 2004 and Prendini & Loria, 2020). Total length of adults 90–125 mm (male holotype 117 mm; Couzijn, 1981). Base color of adults uniformly black, cuticular surface weakly to moderately lustrous ( Figs. 72– 75 ). Carapace surface essentially smooth, with few granules scattered on lateral surfaces but absent in anteromedian area; dorsal profile triangular (resembles isosceles trapezoid) ( Figs. 26–27 ). Tergite surface in both sexes smooth with few granules ( Figs. 72–75 ). PTC 15–19 in both sexes. Pedipalp relatively stout and short in both sexes among congeners ( Figs. 72–75 ); chelae of both sexes robust and short, ChL/W: ♂ ♀ 2.0–2.3; FL/ CL: ♂ ♀ <0.74. Dorsal surface of chelal manus smooth in both sexes ( Figs. 36–37 ); prodorsal surface scattered with minute spiniform granules ( Figs. 56–57 ); fixed finger shorter than manus ( Figs. 46–47 ). Proximal lobe on cutting edge of movable finger lacks pronounced sexual dimorphism, but that of the males is slightly larger than females ( Figs. 46–47 ). Telson in adults reddish black to pitch black ( Figs. 10–11 , 18–19 ).

DISTRIBUTION. This species is widely distributed in northern, central, and western Thailand. This species is found in Laos; the record from Cambodia is doubtful (see below).

Figures

Figures 4–11: Comparison of Heterometrus spp. in Thailand, metasoma and telson in dorsal aspect. Figures 4–5. H. cimrmani, male from Trang (4) and female from Nakhon Si Thammarat (5), THNHM. Figures 6–7. H. minotaurus, male (6) and female from Surat Thani (7), THNHM. Figures 8–9. H. silenus, male from Chanthaburi (8) and female from Chonburi (9), TUPC. Figures 10–11. H. laoticus, male (10) and female from Lamphun (11), TUPC.

Figures 12–19: Comparison of Heterometrus spp. in Thailand, metasoma and telson in ventral aspect. Figures 12–13. H. cimrmani, male from Trang (12) and female from Nakhon Si Thammarat (13), THNHM. Figures 14–15. H. minotaurus, male (14) and female from Surat Thani (15), THNHM. Figures 16–17. H. silenus, male from Chanthaburi (16) and female from Chonburi (17), TUPC. Figures 18–19. H. laoticus, male (18) and female from Lamphun (19), TUPC.

Figures 20–29: Comparison of Heterometrus spp. in Thailand, prosoma in dorsal aspect. Figures 20–21. H. cimrmani, male from Trang (20) and female from Nakhon Si Thammarat (21), THNHM. Figures 22–23. H. minotaurus, male (22) and female from Surat Thani (23), THNHM. Figures 24–25. H. silenus, male from Chanthaburi (24) and female from Chonburi (25), TUPC. Figures 26–27. H. laoticus, male (26) and female from Lamphun (27), TUPC. Figures 28–29. H. spinifer, males from Yala (28) and Narathiwat (29), TUPC.

Figures 30–39: Comparison of Heterometrus spp. in Thailand, chela in dorsal aspect (trichobothria indicated by red circles). Figures 30–31. H. cimrmani, male from Trang (30) and female from Nakhon Si Thammarat (31), THNHM. Figures 32–33. H. minotaurus, male (32) and female from Surat Thani (33), THNHM. Figures 34–35. H. silenus, male from Chanthaburi (34) and female from Chonburi (35), TUPC. Figures 36–37. H. laoticus, male (36) and female from Lamphun (37), TUPC. Figures 28–29. H. spinifer, males from Yala (38) and Narathiwat (39), TUPC.

Figures 40–49: Comparison of Heterometrus spp. in Thailand, chela in external aspect (trichobothria indicated by red circles). Figures 40–41. H. cimrmani, male from Trang (40) and female from Nakhon Si Thammarat (41), THNHM. Figures 42–43. H. minotaurus, male (42) and female from Surat Thani (43), THNHM. Figures 44–45. H. silenus, male from Chanthaburi (44) and female from Chonburi (45), TUPC. Figures 46–47. H. laoticus, male (46) and female from Lamphun (47), TUPC. Figures 48–49. H. spinifer, males from Yala (48) and Narathiwat (49), TUPC.

Figures 50–57: Comparison of Heterometrus spp. in Thailand, chela in ventral aspect (trichobothria indicated by red circles). Figures 50–51. H. cimrmani, male from Trang (50) and female from Nakhon Si Thammarat (51), THNHM. Figures 52–53. H. minotaurus, male (52) and female from Surat Thani (53), THNHM. Figures 54–55. H. silenus, male from Chanthaburi (54) and female from Chonburi (55), TUPC. Figures 56–57. H. laoticus, male (56) and female from Lamphun (57), TUPC.

Figures 72–75: Heterometrus laoticus, in dorsal (72, 74) and ventral (73, 75) aspects; scale bar = 10 mm. Figures 72–73. Male from Lamphun, TUPC. Figures 74–75. Female from Lamphun, TUPC.