Morocera nigrifrons Ingrisch, 2023

Morris, Glenn K, Ingrisch, Sigfrid, Willemse, Fer, Willemse, Luc, De Luca, Paul A. & Klimas, Dita, 2025, Stridulation songs of some Tettigoniidae (Ensifera, Orthoptera) from Papua New Guinea, Zootaxa 5600 (1), pp. 1-81 : 66-68

Morocera nigrifrons Ingrisch, 2023

( Figs 70–72 )

Specimens studied. Holotype male: Papua New Guinea, Morobe, Bulolo Gorge , wall outside station house, 28 viii 1981, coll. G.K. Morris (Depository NBC Leiden).

Other specimens studied: Papua New Guinea, Morobe: Wau, Mt. Missim , elev. 1120 m (7°10’S, 146°54’E), 13.ii.1963, coll. J. Sedlacek 1 ♀ ( BPBM) ; same locality 28 viii 1981, coll. G.K. Morris (Depository NBC Leiden) . PNG. nr Wau, W.E.I., 25 viii 1981, G.K. Morris (1 ♂) ; PNG, Mt. Missim , 18 viii 1981, G.K. Morris (1 ♀) (Depository NBC Leiden) .

Comments. Ingrisch (2023) elevated Gorochov’s (2016) subgenus Morocera to generic status. The type species of the genus is Morocera (Scytocera) loriae Griffini, 1908 ; a third species is M. peniculosa . The titillators of male Morocera nigrifrons have a very distinctive form (ibid, see his Fig. 2D ): “…so far unique among Agraeciini (I [S.I.] have not seen a similar structure in any other species)”. Over their apical half the titillators curl longitudinally, their lateral edges overlapping into submembranous stilletto-like sheaths covered in fine spicules, enclosing tufts of long hairs.

Measurements. (1 male, 2 females in mm). body: male 21, female 21.0–21.5; pronotum: male 5.5, female 5.0–5.25; tegmen: male 11.5, female 11.5–12.5; hind femur: male 10.25, female 10.7; ovipositor: female 8.0–8.5.

Stridulation. This insect produces transient pulses ( Fig. 72D ) grouped tightly together into trains ( Fig. 72A,B ) with a pulse-train period of 66.5 ms at low 20° temperatures. “Stridulatory file on underside of left tegmen 1.70 mm long, with 78 teeth or 45.88 teeth per mm; about the last 20 teeth very small” ( Ingrisch 2023, his Fig. 2A ). The number of file teeth agree reasonably with the number of pulses in the train): mean number of pulses for 10 calls of one male 65.2. Average duration of train 19.1 ms. The spectrum is a broad band ( Fig. 72C ) between 20 and 38 kHz with an average carrier of 28.4 kHz.

Figures

FIGURE 2. Scanning electron micrographs (SEMs) of A. immunis strigin parts: A) Left tegmen ventral aspect, straight file of broad teeth; B) Oblique foreshortened view of wide transverse vein backing scraper (arrow) on underside of right tegmen; C, D) File teeth close-ups show mid-breadth inflections and gullet nodules.

FIGURE 70. Morocera nigrifrons Ingrisch et al., 2023: A) holotype male lateral aspect; B) allotype female lateral aspect. Field name ‘black frons half tegmen’.

FIGURE 71. M. nigrifrons ventral view left tegmen showing stridulatory file.

FIGURE 72. M. nigrifrons acoustic analysis, an example of transient stridulation: A) Three calls taken from a longer series; B) Train of multiple transient tooth events at higher time resolution; C) Spectrum mainly ultrasonic 20–35kHz, using ultrasoniclimited B&K mic ½” 4165; D) Time sample from pulse train of C showing sequential similarity of complex waveforms.