Cestrophorus ditachus, Braun & Morris, 2022

Braun, Holger & Morris, Glenn K., 2022, New species of awl-head katydids, Cestrophorus and Acanthacara, from the Andes of Ecuador (Orthoptera, Conocephalinae, Cestrophorini), Journal of Orthoptera Research 31 (2), pp. 143-156 : 143

Cestrophorus ditachus sp. nov.

Figs 8C, D , 13

Gymnacoustes ditachus (' Gymnacoustes ditachus ' Morris, 1987)

Material examined. -

Holotype: ECUADOR • ♂; old Baeza; 11 Jul. 1985; G.K. Morris leg.; SN-2, MLP . Paratypes: ECUADOR • 1 ♂; old Baeza ; 10 Jul. 1985; G.K. Morris leg.; 85-1, Glassy Tegmina, ANSP • 1 ♂; Tungurahua; 25 Feb. 1985; G.K. Morris leg.; GLASSY TEG, SN-3, ANSP • 1 ♀; Cosanga ; 19 Feb. 1988; G.K. Morris leg.; MLP • 1 ♀; Cosanga ; 19 Feb. 1988; G.K. Morris; ANSP .

Etymology. -

Named for its two-part, two-pulse-rate, song structure, readily apparent to the human ear in real time. Greek δι di [two], ταξηοσ tachos [speed]. This insect is also named (inadvertently but deservedly) for Dita Klimas, katydid field photographer extraordinaire.

Diagnosis. -

More slender and uniformly colored than C. paradoxus , with shorter tegmina. General coloration pale greenish; in males, metazona of pronotum with brown trapezoidal spot fringed by elongate whitish lateral spots. Male tegmina leaving abdomen tip exposed. Females uniformly greenish and apterous. Male cerci with obtusely triangular dorsal lobe (internally with inconspicuous toothlet at the tip) and robust inward-curved acuminate spine, baso-ventral spine with broad base and tapering in perpendicularly upcurved tip; above it on same lobe, another short spine (difficult to see). Styli completely reduced.

Measurements. -

Male: midline pronotum 4.3 mm, fastigium verticis 1.7 mm, tegmen 7.5 mm, hind tibiae 8.6 mm; female: midline pronotum 4.1 mm, hind tibiae 9.7 mm, ovipositor 8.7 mm (based on holotype and one paratype).

Field notes. -

We hunted in light rain at the [historic pre-earthquake] townsite of Baeza, along a muddy rock-strewn trail fenced by barbed wire, uphill beyond the hospital and cemetery on the night of July 10, 1985. We recorded and captured one male ‘agraeciine’ of "pearly pale cast", [like C. paradoxus ] with white maculae prominent laterad on its pronotal metazona, its very pale greenish tegmina shorter than the abdomen, and its eardrums not recessed behind slits [field name 'glassy tegmina’]. This specimen is now the holotype male. On July 11, GKM recorded another singer up the eastern branch of the trail above Baeza but failed to capture him.

On July 25, 1985, we drove from Quito and parked part way up Volcán Tungurahua at signed "ecological reserve" hut under construction, below Pondua. Many C. ditachus sp. nov. were heard singing from shrubby vegetation scattered about a pasture (never a bovid seen). GKM "recorded a male singing from well above my head in a clump of bamboo and one small hardwood tree. After recording, we bent the bamboo down and searched the foliage with our lights," finding and capturing the presumed singer. "As we left the immediate vicinity of the road and climbed several hundred feet, the incidence of [C. ditacus sp. nov.] singers declined to zero. They had ceased calling by 10:30 pm. Chilly and soon one could only hear single quiet lisps recurring at intervals of several seconds, presumably Acanthacara incisa. "

Figures

Fig. 8. Cestrophorus spp. male genitalia compared. A. White pronotal maculae of C. paradoxus; B. Parameres of C. paradoxus ' upside-down dancing anteaters'; C. Dorsal aspect C. ditachus parameres; D. Lateral view of C. ditachus paramere; E. Photo of terminalia of C. amplitenuis; F. Lateral aspect of C. amplitenuis paramere.

Fig. 13. Field-recorded song (Sony Walkman, audio range only) of C. ditachus: trains of pulses characterized by two different pulse rates, slower (SPR) and faster (FPR). A. Two complete calls taken from an ongoing sequence. Single SPR train prefaces a 9 FPR-train sequence; B, D. FPR trains at higher time resolutions showing waveform of rapid-decay pulses; C, E. SPR train at higher time resolution showing waveform of rapid-decay pulses; F, G. Audio-limited spectra of FPR and SPR respectively; spectra unaffected by scraper speed, peaking at 6 - 10 kHz.