Pachycondyla comorensis (André), Andre

Rakotonirina, Jean Claude & Fisher, Brian L., 2013, Revision of the Pachycondyla wasmannii - group (Hymenoptera: Formicidae) from the Malagasy region, Zootaxa 3609 (2), pp. 101-141 : 120-122

Pachycondyla comorensis (André)

( Figures 1 , 4 , 38–39 , 59 )

Ponera comorensis André, 1887: 292 . Lectotype worker, present designation, Antsiranana, Nosy Be (Ernest André 1914) AntWeb specimen code: CASENT0101406 (MNHN) [examined]. Paralectotype workers with the same data but pins coded as CASENT0101407 (MNHN) and CASENT0102011 (MSNG) [examined]. [Combination in Bothroponera: Forel, 1891: 129 , pl. 4, fig. 5; Dalla Torre 1893: 36; Combination in Pachycondyla (Bothroponera) : Emery, 1901: 45, Forel, 1907: 14, Emery 1911: 78; Combination in Bothroponera: Wheeler, 1922: 1007 ; Combination in Pachycondyla by Bolton, 1995: 304].

Worker diagnosis:

Larger species (HW: 2.49–3.13 mm), antennal scape extending beyond the rear cephalic border; anterior margin of clypeus truncate; eyes not breaking the outline of the sides of head; dorsum of head and mesosoma finely striate, with sparse punctures; stout erect hairs on dorsum of head and the rest of body much more inclined to the body surface.

Worker measurements (n=10): HL: 2.94–3.49, HW: 2.49–3.13, CI: 85–92, SL: 2.47–2.95, SI: 94–99, PW: 1.95–2.30, WL: 4.13–4.98, NL: 1.34–1.62, NW: 1.45–1.67, NH: 1.64–1.94, DNI: 99–115, LNI: 110–126.

Description:

Worker. Head roughly as long as broad, broadest behind eyes on posterior third; sides very slightly convex but converging near base of mandibles; posterior margin weakly emarginate medially. Eyes moderately large, located more to the front and not breaking outline of sides of head. Antennal scape relatively long and extending beyond posterior cephalic margin. Anterior margin of clypeus truncate, not projecting into lobe, but rather straight or feebly notched medially; with head in profile, median portion perpendicular to mandibular surface. Mandibles triangular, apical margins bearing eight to nine teeth and denticles. With mesosoma in profile, outline of dorsum almost continuously convex, without distinct angle between propodeal dorsum and declivity, lateral margins of the latter also generally indiscernable. Mesopleural sulcus visible but incomplete. With petiole in dorsal view, anterior margin rounded and posterior margin straight. In profile, petiole nodiform, with rounded anterodorsal portion and distinct angle in the posterodorsal margin.

Mandibles costate or sometimes smooth with effaced fine striation, and with scattered punctures from which hairs arise. Dorsum of head densely striate and superimposed with piliferous punctures from level of eyes and frontal lobes; striation radiating towards occipital corners on each side of midline of head. Dorsal sculpture of pronotum variable, either densely finely costulate or smooth and shiny with trace of striation between sparse punctures, mesonotal and propodeal dorsum with transverse, dense, and fine striation or microreticulation which becomes fairly effaced on some specimens. Lateral portion of mesosoma characterized by a mixture of fine and dense striation and reticulate–rugulation. Declivitous surface transversely finely striate or almost smooth. Lateral portion of petiole node and first two gastral segments microreticulate to densely finely striate, with scattered large punctures which turn into a smooth and shiny surface on dorsum. Upper surface of body with suberect or appressed black, stout hairs, which are shorter on the dorsum of the head and become yellowish brown to brown on appendages; with mesosoma in frontal view, these hairs inclined towards the midline of the mesosoma dorsum, suberect along the dorsolateral margin and much more appressed near the midline. Slender brownish hairs present on ventral surface of head, gaster, and coxae. Body covered with abundant pubescence except head, dorsum of propodeum, petiole node, and third and anterior half of fourth abdominal segments. Coloration is black with reddish articulations and apices of appendages.

The queen caste is unknown for P. c o m o re n s i s.

Discussion:

Pachycondyla comorensis can be easily confused with P. t a v a r a t r a at first glance. Yet the shape of the anterior clypeal margin, the location of the eyes, and the standing degrees of pilosity on the dorsum of the body allow the separation of these two species. Pachycondyla comorensis has a truncated anterior clypeal margin, eyes that do not break the outline of the sides of the head, and subdecumbent to decumbent stout hairs on the dorsum of the body. The morphological similarity of these two species could be attributed to their adaptation to different ecological habitats in northern Madagascar. Pachycondyla comorensis generally inhabits dry forest and lowland rainforest habitats, whereas P. t a v a r a t r a occupies montane rainforests. Data from different collecting events over several years suggest that these large species may not have a morphologically typical queen caste as do other species within the genus, but reproduce through one or more ergatoid or gamergates in the same colony. The absence of alate queens reduces the spatial connection between geographically distant populations because dispersal must occur by budding.

Distribution and biology:

Pachycondyla comorensis is known only from Madagascar, where it generally occupies dry and lowland humid forests and the coastal region in the north of the island ( Fig. 59 ). Despite its name, P. c o m o re n s i s is not known from the Comoros. This is one of two species with longer antennal scapes which are probably used to forage on the soil surface and in leaf litter. Colonies have been found frequently in the ground, in rotten logs, under stones, rarely in dead twigs and rotten sticks on the ground, and under layers of roots and litter on rock.

Other material examined:

MADAGASCAR: Antsiranana: [Nd. Madagascar, Amber Gebirge Nd. Madagascar H. Rolle, Berlin, S.W.11.] (MHNG); [Nossi-bé; Museum Paris Collection, Ernest André 1914] (MNHN); [Nossi-bé] (MSNG); F Lokobe, Nossi-Be Island (E.S. Ross) (MCZC); Nossi-Be (G.B. King) (MCZC); Nosy Be, 4 km ESE Andoany (=Hellville), - 13.41667, 48.3, 200 m, rainforest (P.S. Ward) (MCZC); Nosy Be, Lokobe Forest, -13.41639, 48.30722, 20 m, lowland forest (G.D. Alpert) (MCZC); Nosy Be: RNI Lokobe, 6.3 km 112° ESE Hellville, -13.41933, 48.33117, 30 m, rainforest (Fisher, Griswold et al.) (CASC); Nosy Be: 4 km ESE Andoany (=Hellville), -13.41667, 48.3, 200 m, rainforest (P.S. Ward) (PSWC); NE, 80 km N Ambilobe; no. 2103 (J.M. Wilson) (BMNH); 5 km S Sambava, - 14.65, 50.16667, coastal forest and vanilla (W.L. & D.E. Brown) (MCZC); ridge behind Sambava, second growth forest (W.L. & D.E. Brown) (MCZC); Ampasindava, F d'Ambilanivy, 3.9 km 181° S Ambaliha, -13.79861, 48.16167, 600 m, rainforest (Fisher, Griswold et al.) (CASC); F Ambato, 26.6 km 33° Ambanja, -13.4645, 48.55167, 150 m, rainforest (B.L. Fisher) (CASC); F d' Antsahabe, 11.4 km 275° W Daraina, -13.21167, 49.55667, 550 m, tropical dry forest (B.L. Fisher) (CASC); F d'Ampombofofo, -12.09949, 49.33874, 25 m, littoral forest (B.L. Fisher et al.) (CASC); F d'Ampondrabe, 26.3 km 10° NNE Daraina, -12.97, 49.7, 175 m, tropical dry forest (B.L. Fisher et al.) (CASC); F d'Analabe, 30.0 km 72° ENE Daraina, -13.08333, 49.90833, 30 m, littoral rainforest (B.L. Fisher et al.) (CASC); F de Bekaraoka, 6.8 km 60° ENE Daraina, -13.16667, 49.71, 150 m, tropical dry forest (B.L. Fisher et al.) (CASC); F de Binara, 7.5 km 230° SW Daraina, -13.255, 49.61667, 375 m, tropical dry forest (B.L. Fisher et al.) (CASC); RS Manongarivo, 10.8 km 229° SW Antanambao, -13.96167, 48.43333, 400 m, rainforest (B.L. Fisher) (CASC); RS Manongarivo, 12.8 km 228° SW Antanambao, -13.97667, 48.42333, 780 m, rainforest (B.L. Fisher) (CASC); RS Ankarana, 7 km SE Matsaborimanga, -12.9, 49.11667, 150 m, rainforest (P.S. Ward) (PSWC); RS Ankarana, -12.90056, 49.14722, 150 m (G.D. Alpert) (MCZC); RS Ankarana, 13.6 km 192° SSW Anivorano Nord, -12.86361, 49.22583, 210 m, tropical dry forest (Fisher, Griswold et al.) (CASC); RS Ankarana, 22.9 km 224° SW Anivorano Nord, -12.90889, 49.10983, 80 m, tropical dry forest (Fisher, Griswold et al.) (CASC); RS Ambre, 3.5 km 235° SW Sakaramy, -12.46889, 49.24217, 325 m, tropical dry forest (Fisher, Griswold et al.) (CASC); Makirovana Forest, -14.103, 50.0198, 390 m; -14.1707, 49.9541, 415 m; -14.1604, 49.9522, 550 m, rainforest (Fisher et al.) (CASC).

Figures

FIGURES 1 – 2. Full-face view of the head showing the length of the antennal scape; Fig. 1: scape surpassing the posterior cephalic margin; Fig. 2: scape not surpassing the posterior cephalic margin.

FIGURES 3 – 4. Shape of the clypeus and location of the eyes when head in full-face view; Fig. 3: P. t a v a r a t r a, anterior clypeal margin broadly triangular; eyes breaking the lateral margin of head; Fig. 4: P. c o m ore n s i s, anterior clypeal margin truncate; eyes not breaking the lateral margin of head.

FIGURES 30 – 39. Full-face view of the head and lateral view of the body of the worker caste of Pachycondyla cambouei and its various forms; Figs 30 – 31: Form 4, CASENT 0034474; Figs 32 – 33: Form 5, BLF 0976 (40) - 2; Figs 34 – 35: Form 6, CASENT 0027983.

FIGURES 59 – 64. Distributional maps of Pachycondyla wasmannii - group from the Malagasy region. Fig. 59: P. c o m o re n s i s; Fig. 60: P. p e r ro t i; Fig. 61: P. planicornis; Fig. 62: P. tavaratra; Fig. 63: P. v a z i m b a; Fig. 64: P. wasmannii.