А Review of Heterometrus in Thailand (Scorpiones: Scorpionidae)
Author
Kawai, Kazusa
Author
Unnahachote, Thornthan
Author
Suttisatid, Yossaphon
Author
Tang, Victoria
text
Euscorpius
2023
373
1
25
journal article
10.5281/zenodo.8108977
1536-9307
8108977
87F75781-5547-4D0F-8DA3-8B64E41B3879
Heterometrus minotaurus
Plíšková et al., 2016
,
stat. rev.
(
Figures 6–7
,
14–15
,
22–23
,
32–33
,
42–43
,
52–53
,
60–61
,
67–71
;
Table 1
)
http://zoobank.org/urn:lsid:zoobank.org:act:7D62EBF1-
8AAD-4D32-B68D-EB6A2EB5625D
Heterometrus spinifer spinifer
:
Couzijn, 1981: 89–91
(misidentification, part).
Heterometrus spinifer solitarius
:
Couzijn, 1981: 96
(misidentification, part).
Heterometrus minotaurus
Plíšková et al., 2016: 467–474
, figs. 1–23.
Heterometrus laevigatus
:
Prendini & Loria, 2020: 236–237
, 240–241, 245 (part), figs. 7E, 9E, 10, 23A, B, 37A, B, 50A–D, 67D, 68D, 69D, 158, 164–168 (part), table 2 (part).
TYPE LOCALITY AND
TYPE
DEPOSITORY
.
Thailand
,
Surat Thani Prov.
,
Phanom District
,
8°52'N
98°36'E
,
395 m
a. s. l.
;
FKCP
.
MATERIAL EXAMINED.
Thailand
,
Phuket Province
,
Phuket
Island
,
1 subadult
,
TUPC
;
Surat Thani Province
,
Chaiya District
[
09.44°N
99.08°E
],
1♂
(THNHM-Ar-00000007)
1♀
(THNHM-Ar-00000008),
25 August 2021
, leg.
T
.
Unnahachote
,
Pa We
[
07.84°N
98.31°E
],
5♂
5♀
,
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.
DIAGNOSIS (modified from
Plíšková et al., 2016
). Total length of adults
83–102 mm
(male
holotype
83 mm
). Base color of adults uniformly black, cuticular surface moderately lustrous (
Figs. 67–71
). Carapace with dorsal essentially smooth and laterals heavily granulated; dorsal profile triangular (resembles isosceles trapezoid) (
Figs. 22–23
). Tergite surface smooth with few granules in both sexes (
Fig. 67
). PTC
14–18 in
both sexes. Pedipalps relatively elongated (more slender in males, thicker and shorter in females) among congeners (
Figs. 68–71
); ChL/W:
♂
3.2–3.4,
♀
2.7–3.0; FL/W:
♂
2.6–3.0,
♀
2.3;
PL
/W:
♂
2.9,
♀
2.4; FL/CL:
♂
1.0–1.1,
♀
0.8. Dorsal surface of chelal manus slightly reticulated in both sexes (
Figs. 32–33
); prodorsal surface scattered with minute spiniform granules (
Figs. 52–53
); fixed finger shorter than manus (
Figs. 42–43
). Male finger relatively straight, manus narrow in vertical aspect (
Fig. 52
). Metasoma with
VSM
intercarinal distance wide;
DL
and
DSM
on metasoma I–IV curved in males; telson in adults reddish black to pitch black (
Figs. 6–7
,
14–15
)
.
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.
DISTRIBUTION. The species is distributed in southern
Thailand
, from Kra Isthmus to the Marui River and
Nakhon Si Thammarat
Mountain Range. This species has also been recorded from
Myanmar
(error).
COMMENTS.
Status of
H. laevigatus
and revalidation of
H. cimrmani
and
H. minotaurus
Heterometrus laevigatus
was originally synonymized with
H. spinifer
by Couzjin (1981: 93), followed by
Kovařík (2004: 40)
;
Kraepelin (1895: 34)
listed both
H. laevigatus
and
H. spinifer
as synonyms of
H. longimanus
. This species was regarded as valid only in
Keyserling (1885: 39)
, apart from the original description (Thorell, 1876b: 221, 222) and
Prendini & Loria (2020)
. However, apart from the differences (reticulations on pedipalp manus, sum length of metasoma I–IV, and trichobothrial distances between
V
series on chela) already noted by Couzjin (1981), the prodorsal surface of the chela differs considerably from that of
H. spinifer
: pronounced spiniform granules are present in
H. spinifer
(
Figs. 38–39
), but they are weaker in
H. laevigatus
(
Figs. 1–2
). Therefore, it is not credible to synonymize
H. laevigatus
with
H. spinifer
.
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 58–61:
Heterometrus
spp.
, post-mating spermatophores in bilateral aspects.
Figures 58–59.
H. cimrmani
from Trang.
Figures 60–61.
H. minotaurus
from Surat Thani.
The
holotype
(and the only type specimen) of
H. laevigatus
is a subadult female labeled as collected from “Nova Hollandia [
Australia
], Melbourne” in 1860 (
Fig. 3
) and was examined by
Prendini & Loria (2020: 237)
who considered it conspecific with
H. cimrmani
, as well as with
H. minotaurus
(
Prendini & Loria, 2020: 240–241
)
. However, they also argued that “…
As in other scorpionid taxa, adult males are important for species identification and delimitation in Asian forest scorpions, and there are several species complexes comprising morphologically similar, range-restricted or narrowly endemic species (Prendini, 2001a)
…
Without series, especially adult males, the diagnostic characters (coloration, granulation, meristic variation) often presented to justify putative new species are unreliable and comparisons made with other species, the adults of which may or may not have been described, invalid
…” (
Prendini & Loria, 2020: 12
). The information of the
holotype
is not sufficient enough to justify their synonymization as it was a single subadult female with erroneous locality. However, the possibility that
H. laevigatus
is either
H. cimrmani
or
H. minotaurus
cannot be discarded. Comparison between subadult females could be biased; thus,
H. laevigatus
is hereby considered as a
nomen dubium
due to the ambiguity of its authentic type locality and the lack of description for adults of both sexes.
Validity of both
H. cimrmani
and
H. minotaurus
is confirmed also by DNA analysis implemented by Charles University in
Prague
(paper in preparation; F. Kovařík, pers. comm.).