Mirollia secunda, Ingrisch, Sigfrid, 2011

Ingrisch, Sigfrid, 2011, New taxa of Mirolliini from South East Asia and evidence for an abdominal gland in male Phaneropterinae (Orthoptera: Tettigoniidae), Zootaxa 2943, pp. 1-44 : 17-19

Mirollia secunda sp. n.

Figs. 2L–M, 11H, 12C–D, 13D, 15G–I, 17A–B, 19H–I, 20F–G, 21D, 22

Holotype (male): Thailand: Chiang Mai, Zoo at foot of Doi Suthep, 350–380 m, 18°48'N, 98°57'E, 5.viii.2006 ex ovo, bred in culture, leg. S. Ingrisch, depository: Museum Koenig Bonn ( ZFMK).

Paratypes: Thailand: 1 female, Chiang Mai, Zoo, 350–380 m, 18°48'N, 98°57'E, 5.viii.2006, leg. S. Ingrisch ( ZFMK); 17 females, 11 males, same locality ex ovo, bred in culture (2 females, 1 male in ZFMK; 2 females, 2 males in EMBT; remainder in CI).

Diagnosis. The new species is similar to M. hexapinna Ingrisch, 1998 and M. ranongi Gorochov, 1999 , with regard to cerci, subgenital plate and phallus sclerites. It differs from both by the peculiar shape of the phallus sclerites with the lateral sclerites having a lobe near base of apical area and the apico-dorsal margin obliquely truncate, the intermediate sclerites have the apex acute, and the medial sclerites are smaller, narrower and with few large teeth at apex. From M. quadripunctata Ingrisch, 1990 that was described from the same mountain, it differs by narrower cerci although they are of similar general shape, the subgenital plate with broadly excised apex, and generally different structure of the phallus sclerites.

Description. Fastigium verticis roughly triangular, moderately descending anteriorly, deeply furrowed; elevated lateral margins forming a small tubercle at tip; vertically sloping at tip, separated from fastigium frontis by a gap (Fig. 11H). Pronotum disc with anterior margin subtruncate or faintly concave; posterior margin widely convex; lateral margins rounded into paranota but apical area flat and margins subangular. Paranota little longer than high or almost as high as long; humeral sinus distinct. Tegmen moderately wide; apex rounded (Figs. 2L–M).

Male. Stridulatory area of tegmen oval triangular; stridulatory vein strongly bulging on dorsal side; following vein also little bulging (Fig. 12C). Stridulatory file on underside of left tegmen 1.60–1.72 mm long; teeth in basal third extremely dense, towards centre and apex dense; with 130–150 teeth, equating 81–87 teeth per mm; at base with 16.4–17.6, in middle with 5.2–5.8 teeth per 0.1 mm (Fig. 13D). Mirror on right tegmen roughly oval with anterior margin straight; with a deep funnel-shaped depression in anterior third 2.30–2.40 mm long, 1.71–1.97 mm wide; index length: width 1.18–1.35 (Fig. 12D). Second abdominal tergite in middle covered by long dense hairs, to which often some glutinous substance was sticking (Figs. 19H–I). Tenth abdominal tergite roundly and deeply excised in middle; basal area of excision bridged by the intersegmental membrane, to which the epiproct is inserted vertically (Fig. 15G). Epiproct tongue-shaped, wide and shallowly grooved. Cerci only moderately strong at base, with a weak internal bump at about end of basal third; afterwards narrow, moderately curved; in apical area with hook-shaped curvation; apex with a small, compressed, curved tooth with acute tip (Figs. 15G, I). Subgenital plate wide at base; with long, narrow, medial, posterior process with slightly deviating margins; at apex with a moderately long obtuse cone at both angles, faintly concave or obtuse-triangular in between (Fig. 15H). Phallus with three pairs of sclerites (Figs. 17A–B): inner pair short, parallel sided, with a few large teeth and also small teeth at apex; intermediate pair styliform with acute tip; lateral pair with long conical shaft and apical area curved dorsomediad with proximal margin concave, distal margin convex and with a round lobe, oblique dorsal margin straight and finely serrulate.

Female. Cerci in apical third curved; apex subacute. Epiproct long triangular with weak medial furrow. Subgenital plate transverse with three apical lobes; the medial lobe much shorter than both lateral lobes (Figs. 20F, 21D). Ovipositor falcate (Fig. 20G).

Coloration. Uniformly green. Antennae with spaced annulation; pedicellus with dark marks. Vertex with a short brown stroke behind compound eyes. Pronotal disc with a pair of indistinct black dots. Tegmen with piles of black dots in cells little conspicuous (Figs. 2L–M). Stridulatory area of male tegmen with a dark brown mark in middle including stridulatory vein (Fig. 12C). Abdominal tergites with red dots and a little larger reddish spot at lateral margins. Hind femur in some specimens with a row of three red dots. Anterior tibia with dark brown lines ornating tympanal opening.

Stridulation (Fig. 22). For sound recording two males were kept separately in a cage a few meters from other specimens including females but within hearing distance. Recording was in darkness and continuous starting at 22.00 h with a portable digital recorder with a recording frequency of 44.1 kHz at a temperature of 21°C. The recording was amplified 2000 fold and run through a high pass filter (> 10kHz) using Amadeus II. That way, stridulation showed a maximum around 18 kHz; but the real frequency peak is probably in the ultrasonic range as it is extremely quiet. The sound pattern has been analysed from 75 min of recording. Stridulation consisted of a continuous but little irregular repetition of double-echemes that were repeated at intervals of about between 1 and 9 seconds, often 2–4 s (mean = 3.5 s, median = 2.81 s, n = 226), longer intervals from 15 s to several minutes were regarded as pauses. One echeme usually consisted of 5–7 pulses and some final reverberation. It took 27–56 ms (mean = 36 ms, n = 13). A double-echeme lasted 106–156 ms (mean = 122 ms, n = 32). At irregular intervals, the double-echemes were replaced by longer chirps with 3–8 echemes, in which the pause between the echemes was longer than in the double-echemes and the number of pulses per echeme especially in the last echeme higher (Fig. 22C). Occasionally these long chirps were preceded by a single-echeme chirp. Sometimes two long chirps followed each other, but usually they were separated by sequences of up to 33 double-echemes (mean = 11.5, median = 9, n = 19). Depending on the number of echemes, the long chirps lasted between 327 and 1075 ms (mean = 744 ms, median = 730 ms, n = 23).

Measurements (11 males, 12 females). Body w/wings: male 30–33, female 32–35; body w/o wings: male 19– 24, female 16–24; pronotum: male 4.3–4.8, female 4.3–4.8; tegmen: male 21.5–24.0, female 25–27; hind wing: male 24–29, female 27.5–30.0; hind femur: male 12–14, female 12.5–14.0; ovipositor: female 6.5–7.0 mm.

Etymology. The name refers to the fact that this is the second Mirollia species found on Doi Suthep. Whereas M. quadripunctata had been collected at the summit, M. secunda was found at the foot of the mountain.