Tetramorium marojejy Hita, 2012

Hita Garcia, F. & B. L. Fisher, 2012, The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy region - taxonomic revision of the T. kelleri and T. tortuosum species groups., Zootaxa 3592, pp. 1-85 : 71-72

Tetramorium marojejy Hita Garcia & Fisher sp. n.

(Figs. 18, 21, 22, 129, 130, 131, 142)

Holotype worker, MADAGASCAR, Antsiranana, Parc National de Marojejy, Antranohofa, 26.6 km 31° NNE Andapa, 10.7 km 318° NW Manantenina, 14.44333 S, 49.74333 E, 1325 m, montane rainforest, canopy moss and leaf litter, collection code BLF09192, 19.XI.2003 (B.L. Fisher) (CASC: CASENT0247334). Paratypes, 8 workers with same data as holotype (CASC: CASENT0247327; CASENT0247328; CASENT0247329; CASENT0247330; CASENT0247333; CASENT0499782; CASENT0499783; CASENT0499784).

Diagnosis

Tetramorium marojejy can be easily distinguished from the remainder of the species complex by the following character combination: antennal scapes short to moderate (SI 79-85); propodeal spines long to very long (PSLI 34-37); anterodorsal and posterodorsal margins of petiolar node situated at about same height; first gastral tergite with numerous standing hairs; uniform orange to pale brown body colour.

Description

HL 1.07-1.14 (1.11); HW 1.00-1.07 (1.05); SL 0.82-0.88 (0.85); EL 0.23-0.25 (0.24); PH 0.50-0.59 (0.54); PW 0.72-0.78 (0.75); WL 1.36-1.49 (1.42); PSL 0.36-0.41 (0.40); PTL 0.35-0.37 (0.36); PTH 0.37-0.41 (0.39); PTW 0.27-0.31 (0.29); PPL 0.35-0.37 (0.36); PPH 0.37-0.41 (0.39); PPW 0.36-0.39 (0.37); CI 91-96 (94); SI 79-85 (81); OI 22-24 (23); DMI 52-54 (53); LMI 37-39 (38); PSLI 34-37 (36); PeNI 37-39 (39); LPeI 89-97 (93); DPeI 77-84 (80); PpNI 49-51 (50); LPpI 88-95 (91); DPpI 101-109 (105); PPI 125-135 (129) (12 measured).

Head longer than wide (CI 91-96); posterior head margin distinctly concave. Anterior clypeal margin medially impressed. Frontal carinae strongly developed, diverging posteriorly, and ending at corners of posterior head margin. Antennal scrobes developed, but very shallow and narrow, without defined posterior and ventral margins. Antennal scapes of moderate length, not reaching posterior head margin (SI 79-85). Eyes of moderate size (OI 22-24). Mesosomal outline in profile flat to weakly convex, moderately marginate from lateral to dorsal mesosoma; promesonotal suture and metanotal groove absent; mesosoma comparatively stout and high (LMI 37-39). Propodeal spines long, spinose and acute (PSLI 34-37); propodeal lobes well-developed, triangular to elongate-triangular, and acute. Petiolar node in profile rectangular nodiform, approximately 1.0 to 1.1 times higher than long (LPeI 89-97), anterior and posterior faces approximately parallel, anterodorsal and posterodorsal margins situated at about same height, dorsum flat to weakly convex; node in dorsal view approximately 1.2 to 1.3 times longer than wide (DPeI 77-84). Postpetiole in profile globular, approximately 1.1 times higher than long (LPpI 88-95); in dorsal view around 1.0 to 1.1 times wider than long (DPpI 101-109). Postpetiole in profile approximately as high as petiolar node and generally appearing slightly less voluminous, in dorsal view approximately 1.2 to 1.4 times wider than petiolar node (PPI 125-135). Mandibles striate; clypeus longitudinally rugose, with four to six rugae, median ruga always present and distinct, remaining rugae variably developed; cephalic dorsum between frontal carinae with 9 to 11 longitudinal rugae, most rugae running unbroken from posterior head margin to anterior clypeus, few rugae interrupted, rarely with cross-meshes; lateral and ventral head longitudinally rugose to reticulate-rugose. Mesosoma laterally and dorsally distinctly longitudinally rugose. Forecoxae with well-developed and conspicuous longitudinal rugae. Waist segments strongly longitudinally rugose. Gaster unsculptured, smooth, and shining. Ground sculpture generally faint to absent everywhere on body. All dorsal surfaces of head, mesosoma, waist segments, and gaster with abundant, long, and fine standing hairs. Anterior edges of antennal scapes with suberect to erect hairs. Body of uniform orange to pale brown colour.

Notes

Tetramorium marojejy is currently only known from two localities: the type locality Marojejy and Anjanaharibe-Sud. Both localities are montane rainforests located in north-eastern Madagascar at altitudes of 1200 to 1325 m. In addition, the new species was mainly collected from leaf litter.

Inside the T. smaug complex the orange to pale brownish T. marojejy is the only species without a dark brown to blackish body colouration, and thus is easil y recognisable. However, not considering body colour, the species differs from T. latreillei, T. sabatra, and T. smaug in the development of the propodeal spines and pilosity. The latter three species all have massive and extremely long propodeal spines (PSLI 48-72) and have either no, few, or several scattered standing hairs on the first gastral tergite, whereas T. marojejy has much less extremely developed propodeal spines (PSLI 34-37) and numerous standing hairs on the first gastral tergite. Tetramorium marojejy also cannot be confused with T. adamsi since the latter species possesses a petiolar node with the posterodorsal margin situated higher than the anterodorsal while both margins are at about the same height in T. marojejy. The remaining species, T. nazgul, is dark brown to black in colour and therefore is also unlikely to be misidentified with the orange to pale brown T. marojejy. The latter has shorter antennal scapes (SI 79-85), a comparatively lower petiolar node (LPeI 89-97), and a lower and narrower postpetiole (LPpI 88-95; DPpI 101-109) than T. nazgul (SI 89-92; LPeI 81-88; LPpI 78-85; DPpI 113-122).

Etymology

This new species is named after the type locality, the Park National de Marojejy, which is one of the most important places for the conservation of biodiversity in Madagascar due to the extraordinarily high diversity of landscapes, habitats, fauna and flora. The species epithet is a noun in apposition, and thus invariant.

Material examined

MADAGASCAR: Antsiranana, 9.2 km WSW Befingotra, Rés. Anjanaharibe-Sud, 14.75 S, 49.46667 E, 1200-1260 m, montane rainforest, 9.-11.XI.1994 (B.L. Fisher); Antsiranana, Parc National de Marojejy, Antranohofa, 26.6 km 31° NNE Andapa, 10.7 km 318° NW Manantenina, 14.44333 S, 49.74333 E, 1325 m, montane rainforest, 19.XI.2003 (B.L. Fisher).