A Survey of the Ants (Hymenoptera: Formicidae) of the Volcanic Caldera of Mt. Melibengoy, Mindanao Island, Philippines

The ants of the volcanic caldera of Mt. Melibengoy in the Allah Valley Watershed Forest Reserve (AVWFR), are surveyed, principally by opportunistic collecting. We report 87 ant species representing 33 genera in six subfamilies. We also report three new species records for the Philippines in addition to 13 new distributional records for Mindanao Island. The new Philippine species records are: Cataulacus granulatus (Latreille, 1802); Myrmecina yamanei Okido, Ogata and Hosoishi, 2016; and Pheidole quadrensis Forel, 1900. The new Mindanao distributional records are Camponotus nigricans Roger, 1863; Camponotus variegatus crassinodis Forel, 1892; Crematogaster subcircularis Mayr, 1879; Parasyscia rufithorax (Wheeler & Chapman, 1925); Pheidole cariniceps Eguchi, 2001; Ph. hortensis Forel, 1913; Ph. spinicornis Eguchi, 2001; Polyrhachis dives F. Smith, 1857; Po. Illaudata Walker, 1859; Po. rastellata (Latreille, 1802); Po. thrinax Roger, 1863; Proceratium papuanum Emery, 1897; and Strumigenys theia Bolton, 2000. The high diversity of ants detected by opportunistic hand collecting suggests that a more intensive survey, using a variety of collecting techniques, will very likely discover more new species and new distributional records from Mt. Melibengoy.  The very diverse native ant community also provides as basis for the high conservation priority of the AVWFR. The knowledge gap of Mindanao ant diversity and its affinity to Bornean ant diversity are briefly discussed.

Keywords: Ant diversity, Lake Holon, new records, South Cotabato