Bioacoustics of Mogannia tenebrosa

Remarks This species resembles Mogannia conica (Germar, 1830) (TL: Java ) because its fore wing also has a broad dark-coloured patch halfway from the base, but M. conica has the reddish postclypeus (vs black in the new species),narrower patch on the fore wing, smoothly rounded distal shoulder of the male pygofer (vs with a short triangular tooth in the new species), and a lobe-like process under the lateral clasper lobe (vs absent in the new species). Also similar is Mogannia funettae Boulard, 2008 from northern Thailand , but like M. conica , M. funettae has the fore wing basal cell clear or tinged with bright colour rather than infuscated with dark brown to match the remainder of the basal fore wing (see Boulard 2013 ). As discussed below, the song of Mogannia tenebrosa Lee and Marshall sp. nov. also suggests a relationship to M. funettae . This species is similar also to Mogannia formosana Matsumura,1907 because of the blackish body colour and the brownish patch on the fore wing, but M. formosana has a much more brightly coloured patch on the fore wing and light colouration on the ventral side of the body. Two other Mogannia previously recorded from the Philippines are Mogannia indigotea Distant, 1917 (TL: Tonkin ) and Mogannia viridis ( Signoret, 1847 ) (TL: Java) although we suspect that they are not distributed in the Philippines . Both differ from M. tenebrosa in the main body colour ( M. indigotea is dark indigo blue, and M. viridis green to ochraceous). While the dark body colour of M. indigotea could be confused in poorly preserved specimens, the fore wing colour pattern is different, with some sections of the fore wing hyaline or tinted in indigotea but fully infuscated in tenebrosa (see Chen et al. 2012 ).

Song ( Figure 16 ) The song of the holotype male was recorded and is illustrated here. The sound is a highpitched staccato buzz that continues indefinitely (at least 62s in our recording). Syllables containing approximately six pulses each are closely grouped or coalesced into echemes comprising four syllables, with the beginning and ending pulses of each syllable sometimes overlapping. The syllables are produced at about 200/s, and the echemes at about 20/s. There is minor amplitude modulation that helps to define the syllables,but otherwise sound intensity and frequency are not regularly modulated.The frequency spectrum is broad,reaching from at least 8 kHz to above 20 kHz, but most energy is concentrated within the range 8–12 kHz. The dominant frequency is about 10 kHz.Males were observed to sing while perching on the upper sides of leaves, as noted by Boulard (2013) for other Mogannia in Thailand . No songs have been published previously for the genus Mogannia in the Philippines . The song of M. funettae , as shown in Boulard (2013) , is very similar to that of M. tenebrosa , differing mainly in having a somewhat faster echeme repetition rate of about 28/s and inter-echeme intervals that are about the same duration as the echemes themselves.