A New Species of Orthotomicus Ferrari 1867 (Curculionidae: Scolytinae: Ipini) from Thailand
Author
Cognato, Anthony I.
text
The Coleopterists Bulletin
1867
62
4
496
499
journal article
10.1649/1105
1938-4394
10111203
Orthotomicus chaokhao
,
new species
(
Figs. 1A
&
2
)
Diagnosis.
Compared to the morphologically similar species,
O. angulatus
Eichhoff, 1878
, the spines on the fifth and sixth interstriae of the male elytral declivity of
O. chaokhao
are reduced to tubercules; and a spine occurs on the face of the elytral declivity near the sixth interstria (
Fig. 1A
). In male
O. angulatus
, the fifth and sixth spines are nearly equal in size to the fourth spine, and a spine on the face of the elytral declivity is absent (
Fig. 1B
). The posterior margin of the elytra is scalloped in both males and females of
O. angulatus
, but is straight in males and females of
O. chaokhao
.
Description.
Holotype
, male, total length
2.6 mm
(2.5–3.0 mm,
n
5
14
), 2.6X longer than wide, antennae, head, legs, thorax, and elytra reddish-brown (
Fig. 2A, B
). Head with frons slightly convex, punctate-setose with scattered tubercles; pair of frontal tubercles above epistomal margin approximately mid-frons larger than other tubercles; median epistomal tubercle at least twice size of frontal tubercles (
Fig. 2C
). Antennal club flattened, with sensillae on anterior face, divided by bisinuate suture (
Fig. 2D
).
Pronotal width 1.0 mm (
0.8–1.2 mm
,
n
5
14
), 1.1X longer than wide; summit approximately on anterior third, scalpriform rugosities with interspersed setae on anterior half; posterior half shiny, deeply punctured with few scattered setae.
496
Fig. 1.
Elytral declivity, male, oblique view of: A)
Orthotomicus chaokhao
and B)
O. angulatus
.
Elytra 1.4X longer than wide, 1.2X longer than pronotum, strial punctures on disk impressed, distance between them less than their diameter; interstrial punctures one half diameter of strial punctures, shallow, uniserial, placed approximately every two strial punctures, punctures near lateral and apical margins more numerous, larger, deeper and setose (
Fig. 2A & B
). Declivital margin of each elytron with two acute spines and three tubercles; first spine arising from second interstria; second spine more than twice length of second spine, arising from fourth interstria on wide tumescence; first tubercle arising from third interstria; second arising from fifth interstria; third arising from sixth interstria; remaining margin costate from sixth interstria to declivital suture (
Fig. 1A
). Declivital face with punctures of approximately same size as strial punctures and with spine near sixth interstria (
Fig. 1A
).
Male genitalia with seminal trough consisting of single flattened, twisted rod and internal sac less than or equal in length to medial tube (
Fig. 2E
).
Female similar to male in most features, except elytral spines and tubercles reduced in size.
Type Material.
Holotype
and
16 paratypes
bear the collection data label: ‘‘
THAILAND
: Chang Mai Pr., Doi Inthanon, Mae Klang Waterfall, el.
420 m
.
GPS
N 18.500
°
,
E 98.668
°
,
10 July 2002
,
Cognato
and
Gillogly Coll’
’;
four paratypes
bear: ‘‘
THAILAND
:
Chiang Mai
,
Bo Luang
, 18
°
08
9
N, 98
°
26
9
E, c.
800 m
, ex
Pinus merkusii
,
20.iv.1971
,
R
.
A. Beaver
;’’
seven paratypes
bear: as previous except, ‘‘
10–15.vii.1971
;’’ and
two paratypes
bear: ‘‘
Chiang Mai Prov.
,
Rd
between
Mae Hong Son
and
Pai
, ex
Pinus
sp.
,
9.xi.1986
,
R
.
A. Beaver.
’’
The
holotype
and
10 paratypes
are deposited in the
A. J. Cook Arthropod Research Collection
,
Michigan State University
,
East Lansing
;
13 paratypes
are in the collection of
Roger Beaver
,
Chiang Mai
,
Thailand
;
2 paratypes
are in the collection of
Miloš Knížek
,
Prague
,
Czech Republic
;
3 paratypes
are in the collection of
Michail Mandelshtam
,
St. Petersburg
,
Russia
;
1 paratype
is in the U.S.
National Museum of Natural History
, Washington D.C.
Etymology.
‘‘Chao Khao’’ translates to ‘‘Mountain People’’ which is the Thai name for the indigenous peoples of Southeast Asia. This species is named in their honor.
Notes.
At Doi Inthanon,
O. chaokhao
was collected from a fallen
Pinus
sp.
along with
Ips acuminatus
(Gyllenhal, 1827)
. At Bo Luang,
O. chaokhao
occurred together with
I. sexdentatus
(Boerner, 1767)
and
I. amitinus
(Eichhoff, 1871)
in
Pinus merkusii
Junghuhn and Vriese. It
replaced
I. sexdentatus
on the upper side of large logs (c.
20–40 cm
diameter), but also occurred on smaller branches with a minimum diameter of
4 cm
.
Fig. 2.
Orthotomicus chaokhao
, male: A) dorsal; B) lateral; C) head; D) antenna; and
E) genitalia.
Discussion.
Specimens of
O. chaokhao
were compared to specimens of most species of
Orthotomicus
except for
O. kuniyoshii
(
Nobuchi 1959
)
and
O. nankinensis
Kurenzov and Kononov 1966
. However based on the descriptions,
O. chaokhao
differed from these species.
Orthotomicus chaokhao
is larger and has a different declivital spine morphology as compared to
O. kuniyoshii
.
Orthotomicus nankinensis
will be synonymized with
O. angulatus
and hence, the diagnostic characters given above will identify
O. chaokhao
from
O. nankinensis
(Mandelshtam, pers. comm.).
In addition, Beaver and Browne (1975) recorded this species as
Orthotomicus laricis
(Fabricius, 1792)
. Subsequent study of the voucher specimens connected with Beaver and Browne (1975) indicated that the morphology of these specimens was nearly identical to
O. chaokhao
.