Mecopoda fallax He, 2019

Heller, Klaus-Gerhard, Baker, Ed, Ingrisch, Sigfrid, Korsunovskaya, Olga, Liu, Chun-Xiang, Riede, Klaus & Warchałowska-Šliwa, Elżbieta, 2021, Bioacoustics and systematics of Mecopoda (and related forms) from South East Asia and adjacent areas (Orthoptera, Tettigonioidea, Mecopodinae) including some chromosome data, Zootaxa 5005 (2), pp. 101-144 : 123-124

Mecopoda fallax He, 2019

Recordings: THAILAND: 3254538 (CI), Phetchabun, Nam Nao 1000 m a.s.l., 13 ix 1989, leg. S. Ingrisch (song and stridulatory organs) . MALAYSIA: CHX066, MALAYSIA: Pahang, Krau Game Reserve (study area) bei Kuala Kerau, Kuala Lompat near Temerloh (3°43’N, 102°16’E), 28 iii–12 iv 1981, leg. K.-G. Heller & M. Volleth (song only) . VIETNAM: one specimen from Vinh Phu , Hoa Binh and Gia Lai Provinces, leg. A. Gorochov; stridulatory file only .

The species was described from China (Liu Yf et al. 2019, Liu Cx et al. 2020), but is obviously more widespread.

The long lasting trilling song of M. fallax ( Fig. 6 ) is composed of quite short song units (less than one second) which are repeated without intervals. Within these units regular changes in amplitude are observed ( Fig. 7 ). The duration of one unit was 0.3–0.8 s in China (T=24–29ºC; Liu Yf et al. 2019, Liu Cx et al. 2020), 0.7 s in Thailand (T=21.5ºC) and 0.2 s in Malaysia (T=27ºC).

M. fallax has a long stridulatory file carrying about 110 teeth ( Fig. 11 E ). Concerning the inter-tooth distances, the file is relatively homogenous. The distances start anally around 40–50 µm, reach the maximum at about 60–70 µm and become smaller than 40 µm only very near to the articulation ( Fig. 12 ).

It will be interesting to study the songs and the relationships between the two Vietnamese species M. prominens and M. ampla and the widespread M. fallax . All three have with quite similar files ( Figs. 11–12 ) and occur in Vietnam.

Figures

FIGURE 6. Oscillograms of the calling songs of species of the Mecopoda niponensis subgroup and of M. cf. yunnana. Overview (12 s sections).

FIGURE 7. Oscillograms of the calling songs of species of the Mecopoda niponensis subgroup. Details (1 s sections). In M. himalaya synchronous registration of movement of left tegmen and sound (upper line: upward deflection indicating opening, downward closing; lower line: sound).

FIGURE 11. Stridulatory files in Mecopoda and Eumecopoda. A M. niponensis niponensis, lectotype, B M. niponensis vietnamica subsp. nov., holotype, C M. himalaya, CH3737 (Malaysia), D M. himalaya (=M. ampla malayensis, holotype), E M. himalaya (=M. ampla javaensis, holotype), F M. himalaya (=M. fallax aequatorialis, holotype), G M. macassariensis, holotype, H M. fallax, Thailand, I M. stridulata stridulata, CRTmeceloM02 (Borneo), J M. stridulata stridulata, holotype, K M. paucidens sp. nov., (Java), L M. sismondoi sp. nov., holotype, M M. javana, neotype, N M. javana, Sri Lanka, O M. mahindai sp. nov., holotype, P M. angusta, CH3697, Q M. dilatata, ORT 2005/413 (Borneo), R E. cyrtoscelis zhantievi subsp. nov., holotype, S M. prominens, holotype, T M. ampla ampla, holotype. Scale 1 mm.

FIGURE 12. Inter-tooth spacing in stridulatory files of Mecopoda species. Thick lines and filled symbols indicate specimens with known song. A–D: M. elongata group: A M. niponensis subgroup and M. marmorata, B M. himalaya and macassariensis, C M. fallax and species with similar files, D M. confracta subgroup, E other Mecopoda and Eumecopoda species.