Cycloptiloides bimaculatus Tan, Japir & Chung, 2021

(Figs 1A, 2)

Cycloptiloides bimaculata Tan et al., 2021: 410

Cycloptiloides bimaculatus — Tan et al. 2022b: 600

Specimen examined. Holotype: EAST MALAYSIA • ♂; Sabah State, Sandakan, Sepilok, Rainforest Discovery Centre; N5.87580, E117.94299, 39.1± 5.4 m.a.s.l.; 9 January 2019, 19h11; on the leaf litter; coll. M.K. Tan, R. Japir, M. Binti & J.L. Yukang; SDK.19.20 (FRC)

Additional specimens examined. EAST MALAYSIA • 1♂; Sabah State, Sandakan, Sepilok, Rainforest Discovery Centre; N5.87554, E117.94135, 54.5± 6.1 m.a.s.l.; 11 May 2022, 20h58; on the leaf litter; coll. M.K. Tan & T. Robillard; SBH.22.19 (FRC) • 1♂; Sabah State, Sandakan, Sepilok, Rainforest Discovery Centre; N5.87416, E117.93786, 89.2± 6.8 m.a.s.l.; 18 May 2022, 20h07; on the leaf litter; coll. M.K. Tan & T. Robillard; SBH.22.152 (MNHN) • 1♂; Sabah State, Sandakan, Sepilok, Rainforest Discovery Centre; N5.87328, E117.93749, 95.1± 5.6 m.a.s.l.; 18 May 2022, 20h57; on the leaf litter; coll. M.K. Tan & T. Robillard; SBH.22.153 (FRC) • 1♂; Sabah State, Sepagaya Waterfall, near Lahad Datu; N4.98354, E118.14498, 182.4± 7.4 m.a.s.l.; 13 May 2022, 11h39; on the leaf litter; coll. M.K. Tan & T. Robillard; SBH.22.50 (ZRC) • 1♂, 1♀; Sabah State, Mount Silam, lowland forest; N4.97589, E118.19060, 341 m .a.s.l.; 13 May 2022, 20h; on the leaf litter; coll. M.K. Tan & T. Robillard; TR22-10 (MNHN)

Distribution. Borneo, Sabah State: Sepilok, Mount Silam [new locality record], Sepagaya near Lahad Datu [new locality record]

Type locality. EAST MALAYSIA, Sabah State, Sepilok

Calling song (1 ♂, in captivity, 26.4°C) (Fig. 2). The calling song generally consists of a sequence of echemes which can be highly variable in duration (8–26 s). The echeme sequence typically begins with the echemes more erratic in terms of number of syllables, syllable durations and intervals. Each echeme is made up of 4–10 syllables (= pulses), and has an average duration of 140.9±65.3 ms (78.0–249.1 ms). Consecutive echemes have an average interval of 371.6±86.3 ms (285.6–474.3 ms). The average syllable duration is 14.1±1.5 ms (11.9–15.6 ms) and the average interval between consecutive syllables is 7.2±1.6 ms (5.4–9.7 ms). The dominant frequency is 8.34 kHz.

Compared to the continuous trill of Cycloptiloides timah Ingrisch, 2006 from Singapore (see Tan et al., under review), the calling song of C. bimaculatus also differs by a distinctly shorter syllable duration (14.1 ms in C. bimaculatus vs. 25.7 ms in C. timah) and by the intervals between consecutive syllables (7.2 ms vs. 104.5 ms). The dominant frequency is also distinctly lower (8.3 kHz vs. 9.1 kHz). It should be noted that the average temperature of the recordings for the two species are different (26.5°C in C. bimaculatus vs. 30.5°C in C. timah), which may have contributed partly to the differences in the call parameters between the two species.