Crematogaster hazolava

Crematogaster hazolava is moderately common in humid forests of eastern Madagascar, with a few disjunct occurrences in the central highland region (P.N. Ranomafana, Ambatovy, Analamay). The species seems predominantly adapted to littoral, low and mid elevation forests, but has been collected from a wider altitudinal range (20–1300 m). It is found in sympatry with Crematogaster madagascariensis and Crematogaster kelleri. Curiously, this species also has a yellow, less common form that partly co-occurs with the yellow form of C. kelleri. Many colonies of C. hazolava have been collected nesting in dead twigs or branches, and a few have been found under bark. This species appears to nest exclusively arboreally. When found together with C. kelleri, this species occurred only in low abundance: during a canopy study at R.N.I Betampona that sampled 48 trees, only seven colonies of C. hazolava (in comparison to 18 colonies of C. kelleri) were obtained.

Identification
A member of the Crematogaster kelleri group. Blaimer and Fisher (2013) - Within the C. kelleri-group, workers of C. hazolava can be separated from Crematogaster kelleri and Crematogaster tavaratra by the position of the propodeal spiracle, which is situated confluent with the base of the propodeal spines in C. hazolava, instead of below the spine base in the two latter species. From Crematogaster madagascariensis workers are most easily separated by body size and coloration, the former being mostly larger (HW 0.86–1.11, WL 0.92–1.16) than C. hazolava (HW 0.66–0.89, WL 0.70–0.97). Brown-colored workers of C. hazolava could potentially be confused with C. madagascariensis, but these can be distinguished by the median postpetiolar stripe. Crematogaster hazolava does not co-occur with C. hafahafa, but in any case workers could potentially be distinguished by larger size and the presence of the median postpetiolar stripe. Queens of C. hazolava can be differentiated from C. kelleri and C. tavaratra queens easily since the metanotum is entirely covered by the scutellum in the former, but projects from below the metanotum in the latter two species. From C. madagascariensis queens of C. hazolava can be distinguished by the presence of the median longitudinal stripe on the postpetiole.

Key to Crematogaster kelleri group workers

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  hazolava. Crematogaster hazolava Blaimer, 2013: 20, figs. 26, 27 (w.) MADAGASCAR.

Worker
(n =31) [holotype]. HW 0.66–0.89 [0.84]; HL 0.63–0.84 [0.79]; EL 0.14–0.18 [0.16]; SL 0.58–0.74 [0.69]; WL 0.70–0.97 [0.90]; SPL 0.07–0.12 [0.12]; PTH 0.13–0.17 [0.17]; PTL 0.19–0.26 [0.24]; PTW 0.21–0.28 [0.22]; PPL 0.11–0.16 [0.16]; PPW 0.17–0.25 [0.22]; LHT 0.54–0.72 [0.66]; CI 1.04–1.13 [1.06]; OI 0.19–0.23 [0.20]; SI 0.82–0.95 [0.88]; SPI 0.07–0.14 [0.13]; PTHI 0.61–0.75 [0.73]; PTWI 0.82–1.08 [0.94]; PPI 1.33–1.68 [1.37]; LBI 1.27–1.58 [1.36].

Very small to small species (HW 0.66–0.89, WL 0.70–0.97), with characters of the C. kelleri-group and the following refinements.

Masticatory margin of mandibles with four teeth; posterior margin of head in full face view laterally rounded, often medially depressed; midline of eyes situated at midline of head in full face view.

Lateral borders of mesonotum angulate to carinulate, and mesonotum with small posterolateral denticles; posterior face of mesonotum sloping into metanotal groove at 45u; propodeal spines short (SPI 0.07–0.12), spiniform, straight, moderately diverging in dorsal view; propodeal spiracle confluent with base of propodeal spines; petiole suboval, dorsolateral carinulate; median postpetiolar impression deep, clearly bisecting postpetiole into two lobes, and usually lighter colored, appearing as longitudinal stripe (can be difficult to see in yellow specimens).

Erect pilosity and pubescence highly variable, but usually abundant. Color brown or yellow, abdominal segments five through seven often darker.

Queen
(n= 3). HW 1.28–1.37, HL 1.20–1.24, EL 0.32–0.36, SL 0.80–0.88, MSNW 1.01–1.13, MSNL 1.17–1.27, WL 1.99–2.07, SPL 0.04–0.09, PTH 0.28–0.34, PTL 0.37–0.38, PTW 0.39–0.48, PPL 0.29–0.34, PPW 0.37–0.58, LHT 0.92–0.94, CI 1.07–1.09, OI 0.29, SI 0.65–0.67, MSNI 0.83–0.96, SPI 0.02–0.04, PTHI 0.84–0.91, PTWI 1.04–1.30, PPI 1.06–1.50, LBI 2.16–2.25.

Small (HW 1.28–1.37, WL 1.99–2.07), with characters of the C. kelleri-group in addition to the following.

Masticatory margin of mandibles with five to six teeth; antennal scapes short, barely reaching beyond level of ocelli; eyes situated distinctly below midline of head in full face view.

Mesonotum covered entirely by scutellum in dorsal view; propodeal spines very short spines or denticles (SPI 0.02–0.04).

Male
(n= 2). HW 0.59–0.65, HL 0.49–0.51, EL 0.24–0.26, SL 0.09, MSNW 0.67–0.76, MSNL 0.66–0.76, WL 1.15–1.24, SPL 0.00, PTH 0.16–0.17, PTL 0.21–0.23, PTW 0.21–0.23, PPL 0.10–0.13, PPW 0.20–0.26, LHT 0.62–0.66, CI 1.20–1.27, OI 0.50–0.51, SI 0.18–0.19, MSNI 1.00–1.01, SPI 0.00, PTHI 0.85–0.94, PTWI 1.11–1.18, PPI 2.05–2.08, LBI 1.86–1.88.

Medium body size (HW 0.59–0.65, 1.15–1.24). Masticatory margin of mandibles with three teeth; antennae with second and third funicular segment globular, as long as wide, and all funicular segments evenly wide; in full face view ocellar triangle situated at posterior head margin and slightly elevated with respect to rest of face; occipital carinae very distinct, but not forming a thin flange that projects backwards.

Mesoscutum in dorsal view round; scutellum in dorsal view laterally pinched, but evenly so and not tapering from anterior to posterior end, dorsoposterior portion pointed; mesonotum projecting posteriorly as a small point, but nonetheless entirely covered in dorsal view by scutellum; dorsal face of propodeum absent.

Head sculpture shiny throughout; face with a paired row of short erect setae on frons; mesoscutum with scattered short erect pilosity. Color as in worker and queen, head darker.

Type Material
MADAGASCAR: Toamasina: R.N.I. Betampona: -17.91106, 49.21111, 3952445 m, rainforest. Holotype worker: pinned, CASENT0317642 (image on AntWeb), B-I-2b-6-GC4, ex dead branch 6 m above ground, 22.vi.2012, E. H. Lokensgard; original locality label: M’dgascar: Prov. Toamasina: R.N.I. Betampona, -17.91106, 49.21111, 3952445 m, 10.vi.22.vii.12, B. B. Blaimer et al., arboreal coll., B-I-2b-6-GC4; deposited at. Four paratype workers, pinned, same collection and locality data as holotype. #1: CASENT0317679, deposited at ; #2: CASENT0317680, deposited at. #3: CASENT0317681, deposited at. #4: CASENT0317682, deposited at.

Etymology
‘‘Hazolava’’ means ‘‘tall tree’’ in Malagasy, after the species’ association with rainforest habitats and preference for arboreal nesting habits. The name should be treated as a noun in apposition.