Odontomachus banksi Forel, 1910

Sorger, D. M. & Zettel, H., 2011, On the ants (Hymenoptera: Formicidae) of the Philippine Islands: V. The genus Odontomachus Latreille, 1804., Myrmecological News 14, pp. 141-163 : 154-155

Odontomachus banksi Forel, 1910 (Figs. 8, 14, 20, 35, 36, 47)

Odontomachus banksi Forel, 1910: 121 (description of worker, erroneously labelled as "♀" from Mt. Banahaw, Laguna, Luzon); Viehmeyer 1916: 284 (description of gyne from Mt. Banahaw, Laguna, Luzon); Wheeler & Chapman 1925: 71 (distribution: Mt. Banahaw, Laguna, Luzon); Baltazar 1966: 239 (catalogue). Brown 1976: 116, 127 (taxonomy, key, discussion).

Type material examined: Lectotype (worker; MHNG; present designation, Fig. 35) and paralectotypes (2 workers; MHNG), mounted on one pin, from L a g u n a P r o - v i n c e (according to Forel 1910) (labels see Fig. 36).

Notes: There is a discrepancy since the types are workers, but Forel (1910) describes gynes ("♀"). However, we believe that this is due to a typesetting error, as the characters " Mésonotum fortement et largement échancré " [translated: Mésonotum strongly and broadly indented] and "les stries ... du pronotum fines et serrés, parfois longitudinales au milieu" [translated: striae...on pronotum fine and tight together, sometimes longitudinal in the middle] must refer to workers. We select the uppermost worker as the lectotype (Fig. 35).

Additional material examined (59 workers; BMNH, CSW, CZW, NHMW, UPLB, USC): Luzon: L a g u n a: Ubi, no further data, det. W.L. Brown, 1 ∑. C a m a r i n e s N o r t e: SW Daet, San Vicente, Fabrica, Mananap, 6.II. 2001, leg. H. Zettel, E. S. & L. S. Vichozo (264), 4 ∑∑, 17. III.2003, leg. H. Zettel, C. V. Pangantihon & L. S. Vichozo (348), 3 ∑∑. Labo, Tulay na Lupa, Mt. Labo - Mt. Bayabas area, 17.-18.III.2004, leg. H. Zettel & C. V. Pangantihon (382), 9 ∑∑, 18.V.2006, leg. C. V. Pangantihon (P238), 7 ∑∑. C a m a r i n e s S u r: Naga City, ca. 20 km E of city, 5 km E Carolina , slopes of Mt. Isarog, Malabsay Falls, 19.II.1998, leg. H. Zettel (141), 9 ∑∑, 4.III.1999, leg. H. Zettel (192), 18 ∑∑, 4.III.1999, leg. F. Seyfert (19), 6 ∑∑, 20.IX.1999, leg. H. Zettel (208), 8 ∑∑.

Description of worker: Measurements: lectotype: CI 77, 2.80 HW, 3.65 HL, 56 MdI, 2.05 MdL, 4.95 MsL, 1.60 PnW, 1.47 PtH, 1.63 PtL, 0.58 PtW, 132 SI, 3.70 SL, 16 TL worker with smallest HW: CI 67, HL 2.90, HW 1.95, MdI 56, MdL 1.63, MsL 4.13, PnW 1.13, PtH 1.02, PtL 1.16, PtW 0.40, SI 157, SL 3.07, TL 12.38; worker with largest HW: CI 74, HL 3.70, HW 2.73, MdI 55, MdL 2.05, MsL 5.33, SI 138, SL 3.77, PnW 1.59, PtH 1.58, PtL 1.68, PtW 0.58, TL 15.75.

Structures: Striation on head extending from frontal lobes to ocular ridge, rest of head smooth and shiny. Pronotum with round to transverse striation, closed loops and circles may be visible in dorsal view. Mesopleuron with fine transverse striation. Petiole with some fine striation laterally and with long and acute petiolar spine; anterior face of node straight to almost concave.

Pilosity: Pubescence dense, long.

Colour: Bicoloured; head light brown contrasting with reddish brown mesosoma and petiole, dark brown gaster.

Distribution (Fig. 47): Endemic to the Philippines and present only in the central and southern parts of Luzon; records from Laguna, Quezon (Brown 1976), Camarines Norte and Camarines Sur.

Habitats: Only in dipterocarp forests, sometimes degraded, on mountain slopes.

Notes: Odontomachus banksi is the most distinct Philippine member of the O. infandus group species. It can be distinguished from all other species by the relatively long and dense pilosity of the mesosoma and by striation on the petiole. The smooth and shiny posterior of the head is also

present in three other species: Odontomachus philippinus in the Western Visayas, O. scifictus sp.n. on Camiguin, and O. sp. 2 on Mindanao. They have brown heads and a smooth area on the mesopleuron, whereas the head of O. banksi is yellowish orange and its mesopleuron densely and fully striate. A population of O. alius sp.n. from Catanduanes resembles O. banksi in light and (partly) smooth head, but differs in sparse pilosity of mesosoma, fine striation of mesopleuron, distinctly curved petiolar spine (straight in O. banksi ), and brownish gaster (blackish in O. banksi ). The range of O. banksi is within the distribution of the more common O. infandus , which clearly indicates its specific status. See also notes under Odontomachus sp. 1 from Camarines.