On the ants (Hymenoptera: Formicidae) of the Philippine Islands: III. The genus Recurvidris BOLTON 1992
Author
Zettel, H.
text
Linzer biologische Beiträge
2008
2008-07-10
40
1
891
895
http://antcat.org/documents/4783/Zettel_2008_Linzer_Biol_Beitr.pdf
journal article
10.5281/zenodo.5429936
0253-116X
5429936
Recurvidris nigrans
nov.sp.
E t y m o l o g y: The Latin adjective "nigrans" means dark and refers to the dark body colour of the new species that differs from all other hitherto known congeners.
T
y p e m a t e r i a l:
Holotype
worker labelled "
Philippines
: Negros Or., Cuer-\ nos de Negros, Valencia\ Apolong, Casaroro Falls, 28.\ 1.2007, leg.
H. Zettel
(456)", in the
Entomological Collection
of the
University of San Carlos
, Cebu
City
,
Philippines
.
10 paratype workers
labelled "
Philippines
: Negros Oriental\ Cuernos d.N., Valencia\ Apolong, Casaroro Falls\ 3-
4.3.2008
, lg. Zettel (513)" in the
Natural History Museum
Vienna
,
Austria
, and in the author's collection.
T
y p e l o c a l i t y
Philippines
,
Negros Island
,
Negros Oriental Province
,
Cuernos de Negros Mountains
(=
Mount Talinis
), municipality of
Valencia
, barangay
Apolong
,
Casaroro Falls
;
9° 16' N
,
123° 12' E
, c.
500-550 m
a.s.l.
(
GPS
)
.
D i a g n o s i s (worker):Body chiefly blackish brown, funiculusof antenna and tarsi yellowish. Body surface smooth and shiny. Head broad, HW 0.61-0.65, CI 99-103. Cly- peus without distinct carinae. Mandible with four acute teeth on apical margin and one prominent, acute tooth at basal margin (
Fig. 4
). Propodeum dorsally with 1-2 pairs of short decumbent setae, with long, slender, recurved spines (
Fig. 1
), without infradental lamellae between spines and metapleural lobes. Petiole (
Fig. 1
) with very slender peduncle ventrally bearing a spiniform subpetiolar process; node in lateral view forming an acute angle anteriorly (at insertion of anterior setae).
D e s c r i p t i o n (worker):
Measurements of
holotype
: TL 3.2; HL 0.63; HW 0.65; CI 103; SL 0.57; SI 89; PW 0.35; AL 0.86. Measurements of
paratypes
(n = 10): TL 2.9-3.2; HL 0.61-0.64; HW 0.61-0.65; CI 99-102; SL 0.56-0.59; SI 89-94; PW 0.34-0.35; AL 0.81-0.86.
Head (
Figs 2, 3
) broad and smooth, lacking sculpture except hair pits, setiferous pits and some rugae near mandible base. Mandible (
Fig. 4
) smooth and shiny, with some relatively large hair pits, apical margin with four teeth, forth tooth acute, basal margin with one acute tooth almost as large as forth tooth of apical margin. Clypeus (
Fig. 4
) without paired carinae, but with indistinct paired elongate swellings. Eyes (
Fig. 1
) comparatively large, containing 8 ommatidia in longest row. Profile shape of alitrunk, petiole and postpetiole as in
Figure 1
. Alitrunk smooth and polished, with some very fine setiferous pits, only part of mesopleuron with some fine rugae. Promesonotum with 4 pairs of setae plus one median seta posteriorly. Impression behind mesonotum appearing angular in profile. Propodeum comparatively high, dorsal surface with 1-2 pairs of short subcumbent setae in front of spiracle; spines very high, slender, divergent, and in caudal view very narrow (blade-like). Petiole (
Fig. 1
) with 2-3 pairs of dorsal setae; peduncle in profile long and very slender, its dorsal outline distinctly concave and ending posteriorly in a sharp angle at insertions of anterior pair of setae (insertions separated from each other by shallow impression), its ventral outline with long, spiniform subpetiolar process; node low. Postpetiole with 3 dorsal pairs and 1 ventrolateral pair of setae, low and with deep helcium, as typical for the genus. Gaster moderately depressed. Petiole, postpetiole, and gaster polished except for very fine setiferous pits. Colour blackish brown, alitrunk, petiole and postpetiole slightly lighter. Scape of antenna brown, funiculus yellowish. Mandibles brown, distally yellowish. Legs dark brown, but tarsi yellowish.
C o m p a r a t i v e n o t e s:
Recurvidris nigrans
nov.sp.
meets all morphological criteria of the
R
.
kemneri
group listed by
BOLTON (1992)
, i.e., the characteristic dentition of the mandible (
Fig. 4
), the absence of infradental lamellae on the propodeal declivity, and a broad head (
Fig. 2
) (range of CI
94-106 in
the group,
99-103 in
R
.
nigrans
nov.sp.
). This species group contains only two further taxa,
R
.
kemneri
(WHEELER & WHEELER 1954)
from Borneo and Java and
R
.
proles
BOLTON 1992
from Sulawesi. Comparing the key characteristics which distinguish these two species,
R
.
nigrans
sp. nov.
is more similar to
R
.
proles
, because it is relatively large in size, lacks clypeal carinae and bears 1-2 pairs of setae on the propodeal dorsum. The dark body colour of
R
.
nigrans
nov.sp.
differs from both species (as well as from all other congeners!);
R
.
kemneri
is uniformly yellow,
R
.
proles
is yellow with brown head and gaster. Further differences between
R
.
nigrans
nov.sp. and
R
.
proles
are the following: The tooth on the basal margin of the mandible is strongly developed in
R
.
nigrans
nov.sp.
(almost as large as the forth tooth,
Fig. 4
), but small in
R
.
proles
. The dorsum of the propodeum bears short, decumbent setae in
R
.
nigrans
nov.sp.
, but comparatively long standing setae in
R
.
proles
. The subpetiolar process is narrow, relatively long and acute in
R
.
nigrans
nov.sp.
(
Fig. 1
), but small and triangular in
R
.
proles
(for the latter two characteristics see
BOLTON 1992
: fig. 8). "
Recurvidris
sp_phi1" from
Camarines Sur
in southern Luzon (
ALPERT & al. 2008
: see figures) differs from the new species by much smaller size (TL c. 2.1, HW c. 0.4), uniformly yellow colour, and a relatively stout petiolar peduncle in lateral aspect. On average,
R
.
nigrans
nov.sp.
is the largest known species of
Recurvidris
.