Bothroponera pumicosa (Roger)

Ama JOma & Wp MacKay, 2015, Revision of the African Ants of the Bothroponera pumicosa Species Complex (Hymenoptera: Formicidae: Ponerinae), Sociobiology 62 (4), pp. 538-563 : 556-558

Bothroponera pumicosa (Roger)

Figures 18, 19 and Plate 8 ; Map 9

Ponerapumicosa Roger,1860:290 (w)SOUTHAFRICA, Kaffernlande; Bothroponera pumicosa: Mayr, 1862: 717 (w); Joma and Mackay: 2013: 3; Schmidt and Shattuck 2014: 76; Bothroponera pumicata: Raffray, 1887: 21 [Misspelled name for B. pumicosa ( Bolton, 2012) ]; Pachycondyla (Bothroponera) pumicosa: Emery, 1901: 45 ; Stitz 1910: 130; Arnold, 1915: 62; Santschi, 1914: 4 Pachycondyla pumicosa: Forel, 1901: 344 (m); Wheeler, 1922: 771; Wheeler, G. C. and Wheeler, J. 1971: 390 (l); Brown, in Bolton, 1995: 308

Diagnosis: The worker of Bothroponera pumicosa is characterized by a large total length (11- 12 mm). The main distinguishing character of the B. pumicosa worker is the long (up to 0.50 mm or more) golden hairs that are distributed on the entire body including the mandibles, clypeus, and legs. The hairs on the scape are long, at least as long as greatest diameter of the scape. The mandibles are hairy and smooth. The anterior medial margin of the clypeus is convex, “u” shaped, with a raised smooth medial clypeal area on the lower part and is partially carinate on the upper part between the frontal lobes. The lower part of the medial raised area tends to form a groove. The scape does not reach the posterior lateral corner of the head.

Worker Description: (n=5), HL 2.50 - 2.75, HW 2.05 - 2.15, ML 1.30 - 1.40, EW 0.30 - 0.35, EL 0.40, SL 1.75 - 1.80, FL 2.35 - 2.60, WL 3.25 - 3.70, WPL 4.10 - 4.30, PL 1.00, PW 1.20 - 1.25, PH 1.00 - 1.55, CI 82.00 - 78.18, OI 19.51 - 18.60, MandI 51.00 - 52.00, SI 81.39 - 85.36, PetI 120 – 125. Head subquadrate; mandibles with about 8 teeth, covered with hair (0.20 mm in length); maximum clypeal length 1.85 - 2.00 mm; scape not reaching posterior lateral corner of head; maximum frontal lobes width 0.90 - 0.95 mm; frontal furrow well developed; length of malar space from lower edge of eye to base of mandible 0.50 mm; length from upper edge of eye to edge of posterior lobe 1.20 mm; frontal furrow well developed; lower margin of pronotum straight with anteropronotal area forming strongly curved angle, rounded inferior pronotal angle; basalar sclerite oval shaped; mesometapleural suture developed; anterior face of petiole from dorsal view rounded, slightly narrowed, posterior face vertical, slightly concave posteriorly (side view); posterior edge of petiole with slight depression (seen from above); mandibles shiny; antennae, legs, edges of frontal lobes, surface of head densely punctate; pronotum, mesonotum, propodeum, lateropropodeum, and metapleuron densely foveolate; mesopleuron rough with few scattered punctae and foveolae; petiolar and postpetiolar surfaces covered with larger foveolae than those of mesosoma; postpetiolar dorsum partially covered with striae; dorsum of second segment of gaster covered with shallower foveolae than those of petiole and postpetiole, covered with large striae; gastral segments rough, shiny; long golden hairs (up to 0.50 mm or more) distributed on entire body including mandibles, clypeus, legs; hairs on scape long, at least as long as greatest diameter of scape; erect and suberect hairs on body surface as following: head, funiculus, mandibles with long hairs (0.20 mm), hairs on scape about 0.20 mm on far end, about 0.40 mm on near area of scape’s base, hairs on legs about 0.25 - 0.30 mm, on pronotum, mesonotum, propodeum (0.40 - 0.45 mm), on petiole, postpetiole, entire gaster (0.50 - 0.55 mm); head, pronotum, mesonotum, mesopleuron, propodeum, petiole, postpetiole, entire gaster black; femora, mandibles brownish black; tibia, tarsi, antennae, edges of frontal lobes brown.

Comparison: The worker of B. pumicosa has a similar “u” shaped anterior margin of the clypeus as those of B. strigulosa , B. cariosa , B. berthoudi , and B. laevissima . The upper part of the raised area of the clypeus forms a partial carina while it forms a complete longitudinal sharp carina in both B. strigulosa and B. cariosa , but B. berthoudi , and B. laevissima lack the carina. The long hairs (up to 0.50 mm or more) separate B. pumicosa from all of the other members of the B. pumicosa species complex. The hair length of the other B. pumicosa species complex species is less than 0.20 mm for the head; less than 0.25 mm for the pronotum, mesonotum, and propodeum; and less than 0.35 mm for the petiole and postpetiole. The traits of B. pumicosa are very similar to those of B. berthoudi and B. strigulosa , but it can be separated by the longer hairs and the form of the anterior medial border of the clypeus. The length of the hairs on the head of B. strigulosa is 0.07 - 0.13 mm with a few hairs up to 0.16 mm. The length of the hairs of the head of B. berthoudi is 0.20 mm. The hairs on the dorsum of the pronotum, mesonotum and propodeum are 0.25 mm, and 0.07 - 0.16 mm in B. berthoudi and B. strigulosa respectively. The length of the hairs on the petiole and postpetiole in B. strigulosa is 0.15 - 0.18 mm, and those of B. berthoudi less than 0.30 mm. The hairs length comparison of these species with B. pumicosa shows that B. pumicosa has the longest hair length among those mentioned above. The hairs on the entire body of B. berthoudi are up to 0.35 mm in length, but the hairs of B. pumicosa are longer, up to 0.45 - 0.55 mm.

Among the 5 specimens of B. pumicosa , there is one specimen, a worker # 315926, from the LACM, that appears to be different from the others based on hair length. This specimen was collected from South Africa and determined by Forel without any further information. The hairs on the head measure from 0.07 to 0.11 mm, on the mandibles from 0.10 to 0.20 mm, on the scape from 0.14 to 0.21 mm, hairs on the legs range from 0.15 to 0.22 mm, on the anterior part of the pronotum from 0.20 to 0.22 mm, posterior part of pronotum, sides of pronotum, mesonotum and propodeum from 0.05 to 0.15 mm, on edges of posteropropodeum up to 0.22 mm, on the petiole from 0.05 to 0.13 mm, on the postpetiole up to 0.10 mm, on the sides of postpetiole up to 0.22 mm, hairs between the gastral segments (ventrally) from 0.36 to 0.44 mm, on the pygidium up to 0.22 mm and ventrally (hypopygium) up to 0.30 mm. The other characters for this specimen are quite similar to those of B. pumicosa . It is possible it could be a new species, but when more specimens are collected, it can be reevaluated.

Material examined

Type material: SOUTH AFRICA: Kaffernlande, Transkei District, 31°30’0’’ S; 29°0’0’’ E, Bothroponera pumicosa type ( Roger, 1860) (1 w holotype, #11522.) SAM-ENT (Iziko).

Non-type material: SOUTH AFRICA: Eastern Cape Province, Grahamstown, 33°18’0’’ S; 26°32’0’’ E, 21-iv- 1986, N. G. Robertson, C154, u. stone (3w BMNH). SOUTH AFRICA: No further information, Forel det., collection of W. S. Creighton purchased by LACM 1974, Pachycondyla pumicosa Roger , det. Forel (1w # 315926 LACM).

Distribution: Bothroponera pumicosa is known from the Cape Province of South Africa ( Wheeler 1922), the Cape of Good Hope ( Roger, 1860), the Natal, Province of KwaZulu- Natal ( Forel, 1901; Santschi, 1914: 4) and some other workers were collected from a nest in Burntkraal, Cape Province (The Ants of Africa website, accessed March 2014). This species collected also from Cameroon ( Wheeler, 1922) and Mundame, Cameroon ( Stitz, 1910).

Biology and habitat: The type specimen was collected from Kaffernlande, former name of the Transkei and Ciskei regions, both in the Transkei District (per. comm. Dr. Worden) and the Eastern Cape Province, South Africa. The type specimens of B. cavernosa were also collected from Kaffernlande. The habitat in Transkei District is covered with three types of biomes: Grassland, Savanna, and Thicket biomes ( Map 1 ). These species, with B. cariosa , are recognized by their behavior in that they build small colonies under stones in moist clay soils. They are mainly specialized to feed on termites ( Wheeler, 1922; Wheeler and Wheeler, 1971). The worker and male of B. pumicosa were collected from the Cape Province, Natal, South Africa ( Forel, 1901: Arnold, 1915).

Figures

Map 1: The terrestrial ecoregions of Africa (Burgess et al., 2004) used with permission from Island Press, Washington, D. C.

Plate 8: Bothroponera pumicosa, holotype worker.

Map 9. The distribution of B. pumicosa.