Mecopoda himalaya Liu, 2020

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 : 118-119

Mecopoda himalaya Liu, 2020

Mecopoda ampla malayensis Gorochov, 2020 syn. nov.

Mecopada ampla javaensis Gorochov, 2020 syn. nov.

Mecopoda fallax aequatorialis Gorochov, 2020 syn. nov.

The species was described in 2020 from two males in Yunnan, China, but it is obviously quite widespread. Its characteristic song was first recorded in 1985 by Sismondo on Sumatra, and later by others in several localities in Thailand, Malaysia, Brunei and Indonesia (see below). Also the stridulatory file with relatively few teeth seems to be unique (but see below for the Sulawesian species M. macassariensis ) .

Song recordings and stridulatory organs: THAILAND: 3254539 (CI), Tak Ban Mae Salit, Monkrating resort (17°30’N, 98°5’E), 700–800 m a.s.l., 18 ix 1989, leg. S. Ingrisch. MALAYSIA, peninsular: CH 3737, CH 3740, Selangor, Ulu Gombak Field Study Centre (20 km nno Kuala Lumpur) (3°20’N, 101°45’E), 260 m, 8–28 iii 1981 and 12–19 iv 1981, leg. K.-G. Heller & M. Volleth (both songs and stridulatory organs) . MALAYSIA, Sabah: CRT-meceloM01 ( ZFMK), Mt. Kinabalu NP, Poring , 04.10.1993, 500– 700 m a.s.l., leg. K. Riede. INDONESIA: Java: 2534643 (CI) Indonesia West Java Palabuan Ratu, Samudra beach (6°58’S, 106°30’E), 2 iii 1995, leg. S. Ingrisch. NHMUK010210933 , Sumatra: Brastagi [probably Berastagi, 3° 11′N, 98° 31′E], 17 ii 1985, leg E. Sismondo .

Song only. THAILAND: 3254540 (CI) Thailand Nan Doi Phukha , guesthouse near “Pass” (19°15’N, 101°10’E), 1500 m a.s.l., 5 x 1991, leg. S. Ingrisch. INDONESIA: 3254644-5 (CI) Indonesia Java Bogor, Kebun Raya (6°35’S, 106°47’E), 250 m a.s.l., 15 ii 1995, leg. S. Ingrisch (both song) . 3254541 (CI) Indonesia North Sumatra Pematang Siantar (2°59’N, 99°0’E), 400 m a.s.l., 2 iii 1993, leg. S. Ingrisch. 3254646 (CI) Indonesia West Sumatra Maninjau (0°18’S, 100°15’E), 400 m a.s.l., 13 iii 1995, leg. S. Ingrisch.

Stridulatory organs only. THAILAND: Male, Surat Thani Prov. (Malay Peninsula), ~ 40 km WSWof Phanom Town, environs of Khao Sok NationalPark, secondary-primary forest, 20–28 July 1996, A. Gorochov (holotype of Mecopoda ampla malayensis ). INDONESIA: Male, “ Java merid. 1500′ 1891 H. Fruhstorfer”, “104-98”, “Mecopoda elongata № 42” (holotype of Mecopoda ampla javaensis ). Male, Indonesia, West Sumatra Prov., environs of Harau Valley National Park, equator, 24–26 November 1990, A. Gorochov (holotype Mecopoda fallax aequatorialis ; relative mirror width 1.28).

Other material: Males CH3742, CH 3489, 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 and 18–21 iii 1992, leg. K.-G. Heller & M. Volleth. Males CH3741, CH 3750, CH3754, CH 3755, CH3756, MALAYSIA: Selangor, Ulu Gombak Field Study Centre (20 km nno Kuala Lumpur) (3°20’N, 101°45’E), 260 m, 8–28 iii 1981 and 28 ii–24 iv 1984, leg. K.-G. Heller & M. Volleth. Seven pairs of male tegmina CH3411, CH 3412, CH3413, CH 3657, CH3659, CH 3660, CH3691 (2) from the same localities. Females (assumed to belong to himalaya because of large size and green coloration): CH 3743, MALAYSIA: Pahang, Krau Game Reserve (study area) near Kuala Kerau , Kuala Lompat near Temerloh (3°43’N, 102°16’E), 28 iii–12 iv 1981, leg. K.-G. Heller & M. Volleth. CH3745, CH 3749, MALAYSIA: Selangor, Ulu Gombak Field Study Centre (20 km nno Kuala Lumpur) (3°20’N, 101°45’E), 260 m, 8–28 iii 1981, leg. K.-G. Heller & M. Volleth.

Literature data on song: Korsunoskaya 2008 ( INDONESIA: Java), Kostarokas & Römer 2015, Krobath et al. 2017, Siegert et al. 2013 (all MALAYSIA), Liu Cx et al. 2020 ( CHINA), Tan & Wahab 2018 ( BRUNEI).

The most detailed study of the song was undertaken by Krobath (2013; Krobath et al. 2017) under the name ‚trilling species of the Mecopoda complex‘. At intervals of many minutes, the males produce calling bouts which last several minutes and start with an alternation between soft and loud trilling parts and end in a continuous long loud trill ( Krobath 2013; Krobath et al. 2017). The stridulatory movements differ between soft and loud parts. When singing softly, the males make simple to-and-fro movements (single syllables), but during the loud part they alternate between long and short syllables (echemes), as it can be seen in the wing movement recordings ( Fig. 7 ). Period data are given in Tab. 3 . However, the males are heating up during singing by up to eight degrees ( Erregger et al. 2017) with the effect that all time parameters may change during the song. Impulses are produced during both opening and closing of the tegmina ( Fig. 7 ). Opening and closing hemisyllables differ slightly in spectral composition ( Fig. 14 ).

The stridulatory file of himalaya has less teeth (73–98) than that of niponensis and fallax ( Tab. 2 , see also Fig. 12 ). The inter-tooth distances start anally with 60 µm and reach their maximum (between 80 µm and 100 µm) always around the 30th tooth (except one specimen from Thailand with obvious irregularities; Fig. 12 ).

Considering the large range, local variation in file structure as well as in mirror dimensions and other morphological structures are to be expected and do exist (see above listed synonyms). The status of these forms will be established after the relationship to M. macassariensis is solved.

Chromosomes (from holotype): 2n = 27, FN = 54; pair 1 metacentric, pairs 4–14 metacentric or submetacentric, 2 and 3 subacrocentric, X chromosome metacentric ( Fig. 15 ).

Measurements (in mm): CH 3737, 3740: pronotum length 9.5; tegmen length 62–65; tegmen width 15–16; hind femora length 46.0–46.5.

Figures

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 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.

FIGURE 14. Power spectra of the calling songs of Mecopoda species. In A, red line trill, green line chirp; in B–D, grey area opening and closing hemisyllable together, blue line opening hemisyllable only, yellow line closing hemisyllable only (for Eumecopoda opening/closing assumed).

FIGURE 15. C-banded karyotypes (left side) and mitotic metaphase (right side) of five Mecopoda species with different chromosome number (2n). Karyotypes are reconstructed by arranging homologous chromosomes in order of decreasing size. X, sex chromosome.