Crematogaster razana, Blaimer, Bonnie B., 2012

Blaimer, Bonnie B., 2012, Taxonomy and species-groups of the subgenus Crematogaster (Orthocrema) in the Malagasy region (Hymenoptera, Formicidae), ZooKeys 199, pp. 23-70 : 44-46

Crematogaster razana sp. n. Figure 30

Type locality.

MADAGASCAR: Toliara: R.S. Kalambatritra: -23.4185, 46.4583, 1365m, grassland, under stone; 8.ii.2009; B.L.Fisher et al..

Type specimen.

holotype worker:pinned, CASENT0149655, BLF21485; original locality label: MADG’R: Toliara: R.S. Kalambatritra: 23.4185°S, 46.4583°E, 1365m; grassland, 8.ii.2009; B.L.Fisher et al. BLF#; deposited at CASC.

Other material examined

(CASC). MADAGASCAR: Toliara: R.S. Kalambatritra: -23.45373, 46.45773, 1345m; -23.4185, 46.4583, 1365m (B.L.Fisher et al.); P.N. Andohahela: -24.9300, 46.6455, 300m (B.L.Fisher et al.).

Worker measurements

(n=3). Holotype: HW 0.54; HL 0.50; EL 0.13; SL 0.37; WL 0.53; SPL 0.07; PTH 0.12; PTL 0.18; PTW 0.15; PPL 0.12; PPW 0.16; LHT 0.38; CI 1.08; OI 0.26; SI 0.74; SPI 0.14; PTHI 0.68; PTWI 0.86; PPI 1.31; LBI 1.40.

Other material.

HW 0.49-0.56; HL 0.45-0.52; EL 0.12-0.14; SL 0.35-0.40; WL 0.45-0.54; SPL 0.05-0.07; PTH 0.10-0.12; PTL 0.15-0.19; PTW 0.14-0.16; PPL 0.08-0.11; PPW 0.14-0.17; LHT 0.34-0.40; CI 1.07; OI 0.26-0.27; SI 0.76-0.77; SPI 0.11-0.13; PTHI 0.64-0.67; PTWI 0.86-0.92; PPI 1.46-1.70; LBI 1.32-1.37.

Diagnosis.

A combination of protruding eyes and raised sharp lateral carinae on the propodeum (Figure 13) separates workers of Crematogaster razana from workers of Crematogaster rasoherinae and the Crematogaster volamena -group. From other species within the Crematogaster madecassa -group it can be identified by the lack of median vertical carinae on the clypeus (Figure 17) and the absence of long setae on the posterior end of the lateral mesonotal carinae. Crematogaster razana queens are diagnosed by a combination of the presence of very short propodeal spines, large protruding eyes (OI 0.31), and the presence of a median clypeal notch (Figure 20).

Worker description

(Figures 30 A–C). Very small species (HW 0.49-0.56, WL 0.45-0.54), with characters of the Crematogaster madecassa -group, in addition to the following. Clypeus lacking median vertical carinae; antennal scapes just reaching posterior margin of head.

Metanotal groove constricted to about half the width of pronotum; propodeal spines short (SPI 0.11-0.14), in form of acute triangular points, distinctly directed upwards in lateral view, in dorsal view moderately diverging; subpostpetiolar process absent.

Face with no more than 4 erect, long flexuous setae; promesonotum with 4 erect, long flexuous setae: 2 humeral setae, and 2 setae at anterior end of mesonotal carinae (posterior setae absent). Color yellow to yellowish-brown.

Queen measurements

(n=1). HW 1.10, HL 0.91, EL 0.28, SL 0.65, MSNW 0.94, MSNL 0.98, WL 1.74, SPL 0.04, PTH 0.30, PTL 0.45, PTW 0.41, PPL 0.28, PPW 0.46, LHT 0.83, CI 1.21, OI 0.31, SI 0.71, MSNI 1.77, SPI 0.02, PTHI 0.66, PTWI 0.92, PPI 1.65, LBI 2.09.

Queen description

(Figures 30 E–G). Very small (HW 1.10, WL 1.74), with characters of the Crematogaster madecassa -group, in addition to the following. Clypeus with a median notch; antennal scapes just reaching posterior margin of head.

Mesosoma more compact (MSNI 1.77, WL 1.74); mesoscutum in dorsal view about as wide as long; propodeal spines reduced to minute dents (SPI 0.02).

Petiole with one pair of long flexuous setae posterior to denticles.

Male and intermediate

(if existing) unknown.

Distribution and biology.

Crematogaster razana has only been collected at two localities in southern Madagascar (Figure 30B). One of these sites is a dry forest (west ern slopes of P.N. Andohahela), whereas the other collections were made in a montane grassland habitat (R.S. Kalambatritra). Since the few collections of this rare species have been made mostly on the ground (under stone, pitfall trap or on low vegetation), I assume that Crematogaster razana is ground-nesting. This species is sympatric with Crematogaster rasoherinae and parapatric or narrowly sympatric with both Crematogaster madecassa and Crematogaster telolafy in the Andohahela massif.

Etymology.

TheMalagasy word “razana” means ancestor and alludes to the isolated distribution of this species and its phylogenetic position within the Crematogaster madecassa -group. This name should be treated as a noun in apposition.