Bioacoustics of Anthracites zebra

New diagnosis. The species can be characterized by the following: the lateral part of tegmen golden or cream colored ( Figs 2A–D ); the stridulatory file on the left tegmen fairly straight, 1.1–1.2 mm , and consisting of 81–83 teeth (although one specimen from Clarin has only 76 teeth) ( Figs 2E–H ); the knee areas (for all legs) never black/ dark colored; the male cercus short conical with a stout apico-internal process and having a short spinose apex, apicoexternal margin bent at 90° ( Figs 3A–H ); the male subgenital plate at the bottom of the apical excision provided with a stout, long, styliform projection; margin around bases of styli with a triangular, robust dorsal projection ( Figs 3A–H ); the male titillators with the lateral arm/ apical extensions and its apex stiffened and truncated, sometimes slightly enlarged than arms, but always with a small spine pointing ventrad ( Figs 3I–M ).

Discussion. Anthracites sebu Tan, Bahoy & Sabang, 2024 from Lake Sebu in South Cotabato resembles the holotype of Anthracites zebra Hebard, 1922 from Mount Apo in North Cotabato in the coloration of the head, pronotum, tegmina, and legs; as well as the shapes of the male cercus and subgenital plate. The male titillators and stridulatory file of the left tegmina between the A. sebu and the male holotype of A. zebra could not be compared. The light form of A. zebra sensu Bahoy et al. , 2024 from Mount Malindang shares similarities with A. sebu in the male cercus and subgenital plate; but differs by the male titillators having its apical spine at the apex of the lateral arms smaller and less robust, produced rather than extension of apex, and by the coloration of the face, pronotum, and fore tibia. Therefore, A. sebu from South Cotabato may be a junior synonym of A. zebra from North Cotabato . The A. zebra from Mount Malindang, including sensu Bahoy et al. , 2024 and sensu Ingrisch, 2015 , could potentially represent a different species owing to the minute differences in the lateral arms of the male titillators. But at present, it is best to consider all these variants as a single species under A. zebra until we have a better understanding of its distribution between Mount Malindang in Misamis Occidental to South Cotabato in southern part of Mindanao, as well as awaiting the calling song and molecular data.