Typophyllum onkiosternum, Braun, Holger, 2015

Braun, Holger, 2015, Little walking leaves from southeast Ecuador: biology and taxonomy of Typophyllum species (Orthoptera, Tettigoniidae, Pterochrozinae), Zootaxa 4012 (1), pp. 1-32 : 11-12

Typophyllum onkiosternum sp. nov.

( Figs. 8 , 9 , 10 , 11 A–C)

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:463836

Braun 2002: 67 (male as Typophyllum sp. 4, “Schwarzgetüpfeltes Spaziergehblättlein“, female as Typophyllum sp. 5, “Schmetterlings-Spaziergehblättlein“, nymphs as T. egregium ), Braun 2008: 220 ( Typophyllum sp. 4).

Etymology. Referring to the hook-like sternal spines, from Greek onkos (hook, barb of an arrow).

Examined specimens. Male holotype cbt004s01 (sound recording), Cordillera del Consuelo 2150 m, 9 May 1999, leg. H. Braun, deposited in the Museo de La Plata; same site and collector and in collection of author: female paratype cbt005s01, 2110 m, 13 September 1998; two female nymphs: cbt002s12, 2150 m, 13 December 1997; cbt002s16, above 2100 m, May 1999 [erroneously assigned to three different species codes: cbt002, -004, -005].

Description. As in the two preceding species the internal tympanal chamber walls are not extending beyond the dorsal surface of the fore tibia, and the hind tibiae are developed normally, so this species also belongs to Vignon’s first group. As in the other species the tegmina shapes of male and female are very different ( Figs. 8 , 10 ). The speculum of the right tegmen in males is fairly small and transparent. This species has unique black hooklike spines on the meso- and especially the metasterum, described for no other Typophyllum species ( Fig. 8 C,D). The prosternum has very small, short and obtuse processes. On the margins of the mesosternum sit delicate, almost straight and obtuse spines that diverge laterally about 45 degrees. The metasternum is equipped with curved and strongly laterally diverging spines that are longer and reach 1 mm in the male. Upon this character was established the conspecificity of the single male, the very dissimilar female, as well as the two nymphs.

Coloration. The only known male is light brown with greyish and yellowish hues ( Figs. 10 A,D and 11B). Its abdominal tergites have black lateral spots and the sternum is blackened. The only female is light green with dark brown legs and reddish brown ovipositor ( Figs. 10 B,C and 11A).

Measurements. Tegmen length in male 15 mm and in female 23 mm, hind femora in males 14 mm and in females 18 mm.

Acoustic behaviour. The single recorded male produced series of pulse pairs ( Fig. 19 B). At 18ºC the pulse length is 20–30 ms (without the soft hemisyllables corresponding to the opening strokes), and the interval about 50 ms. On a field recording of an untraceable male at 13ºC pulse length is 40 ms and interval 70 ms. These series can consist of 10–15 such pulse pairs, separated by 2–5 seconds respectively. The pulses are broken up into not completely fused impulses, and the spectrogram shows a fairly narrow peak between 20 and 22 kHz.

Distribution. Only known from the type locality: northern slope of Cordillera del Consuelo, 2100–2200 m. All four individuals as well as the only acoustic record are from a small area at the origin of a small creek. The male was sitting on a terrestrial bromeliad.

Figures

FIGURE 8. Typophyllum onkiosternum sp. nov.: A. male habitus; B. left fore and middle femora, external view; C. spines on pro-, meso- and metasternum, frontal view, slightly from below; all spines black, distance between tips of metasternal spines almost 2 mm (A, B, C after holotype cbt 004 s 01); D. metasternal spines of female paratype, frontal view; distance between tips almost 3 mm (cbt 005 s 01); E left tegmen of female paratype (24 mm); F. left tegmen of male holotype (14.5 mm, more schematic than in A).

FIGURE 9. Typophyllum onkiosternum sp. nov.: A. female (paratype, cbt 005 s 01); B. female nymph (cbt 002 s 16).

FIGURE 10. Typophyllum onkiosternum sp. nov.: A, D. male holotype (grey-brown morph); B, C. female paratype (green morph) in lateral and dorsal view (cbt 004 s 01, cbt 005 s 01, photos to scale).

FIGURE 11. Typophyllum onkiosternum sp. nov. (A – C): A. female (paratype, tegmen length 24 mm), B. male (holotype, tegmen length 14.5 mm), C. female nymph (cbt 002 s 12); Typophyllum sp., unknown male of species described from females only or new species (D – F, cbt 003 s 08): D. nymph, E, F. adult; G. Typophyllum bolivari, nymph; photos of live individuals staged during day and approximately to scale.

FIGURE 19. Oscillograms and linear spectrograms of calling songs of four Typophyllum species: A. T. egregium, complete call (field recording, 9.5 ºC, specimen cbt 002 s 21); B. T. onkiosternum sp. nov., one double pulse of longer sequence (cage, 18 ºC, cbt 004 s 01); C. T. morrisi sp. nov., one pulse and below complete call, here consisting of three pulse groups (cage, 23 ºC, cbt 003 s 01); D. T. erosifolium one pulse and below seven double pulses from continuous calling (cage, 20 ºC, cbt 001 s 01); all recordings made at night.