Systematics and biogeography of the ant genus Crematogaster Lund subgenus Orthocrema Santschi in Asia (Hymenoptera: Formicidae)
Author
Hosoishi, Shingo
Author
Ogata, Kazuo
text
Zoological Journal of the Linnean Society
2016
2016-02-10
176
3
547
606
http://dx.doi.org/10.1111/zoj.12330
journal article
126748
10.1111/zoj.12330
6f1d30f9-d20f-415b-a70c-a65074943adf
0024-4082
5358180
SYNOPSIS OF ASIAN SPECIES OF THE SUBGENUS
Orthocrema
The worker caste of the subgenus
Orthocrema
was diagnosed by
Blaimer (2012c)
on a global scale. For the
purpose of taxonomic convenience, we present the following characteristics for Asian fauna:
1. Mandibles with four teeth on the masticatory margin; the teeth located at equal distance each other in most species, but basal tooth located apart from other teeth in subterranean species (
Hosoishi
et al
., 2010
).
2. Palp formula 5, 3 (
Bolton
, 2003
).
3. Anterolateral margins of clypeus not protruded anteriorly (
Hosoishi & Ogata, 2012
).
4. Clypeus usually striated with longitudinal rugulae; the length of rugulae variable in different species.
5. Antenna 11-segmented.
Figure 51.
Geographical distribution of the species of the
C
.
biroi
group.
6. Antennal club 2-segmented. Apical two flagellar segments clearly distinguished in coloration from other flagellar segments especially in the
C
.
baduvi
group.
7. Sensilla basiconica and sensilla trichodea curvata distributed in the apical two flagellar segments (
Hosoishi & Ogata, 2009c
).
8. Compound eye generally distinct and large, but strongly reduced in subterranean species (
Hosoishi
et al
., 2010
).
9. Ocelli rarely present in intermediate workers.
10. Occipital carina distinct.
11. Mesonotal ridges developed dorsolaterally, but weakly developed in
C
.
masukoi
and
C
.
moatensis
.
12. Ventrolateral katepisternal ridge distinct (Hosoishi, 2015).
13. Propodeal spines usually developed, but undeveloped or small tubercles in
C
.
binghamii
.
14. Petiole usually with subparallel sides.
15. Petiole usually with short process posteriorly.
16. Postpetiole not bilobed. If weakly bilobed, usually without distinct longitudinal median sulcus.
17. Fourth abdominal tergite with erect to suberect setae.
18. Body principally yellow, but sometimes partly brown to black in
C
.
binghami
group,
C
.
biroi
group,
C
.
moatensis
group and
C
.
quadriruga
group, but brown in
C
.
baduvi
group.
Figure 52.
Geographical distribution of the species of the
C
.
quadriruga
group.
19. Monomorphic in size; intermediate workers occasionally present.
20. Nesting in soil; some species nesting in dead twigs on lower vegetation.
SYNONYMIC LIST OF ASIAN
Orthocrema
SPECIES
In this study, five species groups are established within the Asian
Orthocrema
. The species groups were defined based on putative apomorphies and discrete morphological boundaries. The species groups recognized here will provide a possible basis for new monophyletic taxa. The
C
.
baduvi
,
C
.
binghamii
and
C
.
biroi
groups are relatively easily defined, but the
C
.
quadriruga
group is probably not monophyletic as currently defined. The
C
.
moatensis
group was represented by a single species since the position of
C
.
moatensis
in cladograms was always consistent. The taxa should ideally be monophyletic, but also considered as useful units for taxonomic purposes in the case of hyperdiverse genera.
Crematogaster baduvi
group
C
.
baduvi
Forel, 1912b
.
C
.
brunensis
sp. nov.
C
.
macracantha
Creighton, 1945
.
C
.
storki
sp. nov.
Crematogaster binghamii
group
C
.
binghamii
Forel, 1904
.
C
.
brevispina
sp. nov.
C
.
longipilosa
Forel, 1907
.
Crematogaster biroi
group
C
.
biroi
Mayr, 1897
.
=
C
.
aitkenii
Forel, 1902a
.
syn. nov.
=
C
.
biroi smythiesii
Forel, 1902a
.
syn. nov.
=
C
.
urvijae
Bharti, 2003
.
syn. nov.
C
.
fritzi
Emery, 1901
.
C
.
luzonensis
sp. nov.
C
.
masukoi
Hosoishi, Yamane & Ogata, 2010
.
C
.
ocellata
sp. nov.
C
.
osakensis
Forel, 1900
.
C
.
reticulata
Hosoishi, 2009
.
C
.
schimmeri
Forel, 1912a
.
C
.
udo
Forel, 1905
.
C
.
vieti
sp. nov.
Crematogaster moatensis
group
C. moatensis
sp. nov.
Crematogaster quadriruga
group
C
.
bandarensis
Forel, 1913
.
stat. nov.
=
C
.
biroi andelis
Santschi, 1928
.
syn. nov.
C
.
celebensis
sp. nov.
C
.
gavapiga
Menozzi, 1935
.
C
.
javanica
Menozzi, 1935
.
C
.
myops
Forel, 1911a
.
C
.
philippinensis
sp. nov.
C
.
quadriruga
Forel, 1911c
.
stat. nov.
C
.
suehiro
Terayama, 1999
.
=
C
.
miroku
Terayama, 2013
.
syn. nov.
C
.
sundalandensis
sp. nov.
The species groups of Asian
Orthocrema
species
Apomorphies of the species groups obtained by cladistic analysis are given in italics.
Crematogaster baduvi
group
Relatively long scape (SI 98–118). Basal flagellar segment (antennal segment III) longer than broad. Propodeal spines long and
directed laterally
.
Postpetiolar dorsum highly convex in lateral view
;
postpetiole distinctly higher than petiole in lateral view
.
This species group is easily distinguished by the propodeal spines directed laterally and highly convex postpetiolar dorsum from other Asian
Orthocrema
species.
Crematogaster binghamii
group
Basal flagellar segment (antennal segment III) longer than broad.
Posterior margins of mesonotum forming short triangle-shaped process in lateral view
. Propodeal spines undeveloped, or developed and directed posteriorly.
Standing pilosity abundant on body surface
.
This species group is easily distinguished by the short triangle-shaped process on posterior margins of mesonotum and long and abundant standing pilosity from other Asian
Orthocrema
species.
Crematogaster biroi
group
Relatively short scape (SI 70–89). Basal flagellar segment (antennal segment III) broader than long.
Anterior margin of pronotal collar almost straight in dorsal view
.
Dorsal surface of propodeum striated with rugulae
. Mesosoma sculptured. Subpetiolar process developed acutely.
Subpostpetiolar process developed acutely
.
This species group is easily distinguished by the subpostpetiolar process developed acutely and sculptured surface of mesosoma from other Asian
Orthocrema
species.
Crematogaster moatensis
group
Two apical flagellar segments not differentiated in coloration. Pronotum distinctly higher than pronotal collar. Metanotal groove not covered by lamellate ridges. Propodeal spiracles oval. Petiole long and slender.
This species group is unique in having the metanotal groove not covered by lamellate ridges, oval-shaped propodeal spiracles and long and slender petiole from other Asian
Orthocrema
fauna.
Crematogaster quadriruga
group
Relatively long scape (SI 81–100). Basal flagellar segment (antennal segment III) broader than long. Subpetiolar process developed. Subpostpetiolar portion wholly convex in lateral view. Mesosoma generally smooth and shining.
This species group is distinguished by the subpostpetiolar portion wholly convex and smooth and shining surface of mesosoma from other Asian
Orthocrema
species.