Oxyecous magnus Ragge, 1956

Naskrecki, Piotr & Guta, Ricardo, 2019, Katydids (Orthoptera: Tettigoniidae) of Gorongosa National Park and Central Mozambique, Zootaxa 4682 (1), pp. 1-119 : 85

Oxyecous magnus Ragge, 1956

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:11092

( Figs. 36 H–K, 54J–L)

Angustithorax spiniger Massa, 2015 syn. nov.

Diagnostic remarks. O. magnus is recognizable by the presence of a low but noticeable median carina on the dorsal surface of the pronotum, particularly in the prozona, making it appear somewhat tectiform ( Fig. 36J ). Like all species of Oxycous, O. magnus possesses a long and narrow process on the dorsal part of the procoxa. The male cerci are long and strongly incurved, with an s-shaped tip ( Fig. 36K ). Unlike O. lesnei , the male tympana do not carry large external auriculae, and the venation of the tegmina is not reduced. The tip of the ovipositor is blunt (pointed in O. lesnei ).

A comparison of the holotype and freshly collected material of O. magnus with the detailed photographs of the recently described Anustithorax spinger Massa (2015) leaves little doubt that these two taxa are conspecific. They have identical morphology of the cerci, head, pronotum, and stridulatory area of the tegmen as well as a very similar body size. For this reason, A. spiniger is here considered a junior synonym of O. magnus .

Bioacoustics. Unlike O. lesnei , this species does not stridulate in flight and males only call from stationary positions. The call consists of a series of 3-syllable echemes produced every 0.7– 1.3 s; mean syllable duration is 0.0062 s (SD=0.00186, n=50); the peak frequency of the call is 10.5–14.6 kHz ( Figs. 54 J–L). The call is audible from a short distance as a series of faint clicks.

Distribution and natural history. O. magnus has previously been known from the Democratic Republic of Congo and Tanzania ( Massa 2015; Ragge 1956b), and here it is recorded from Mozambique for the first time. So far it has only been found in the Sofala Province, where adults can be seen during the rainy months between February and April. This species is associated with woodland savanna habitats and it often occurs sympatrically with O. lesnei .

Measurements (3 males, 2 females). body w/wings: male 45–48 (46.71.5), female 44–45 (44.5.7); body w/o wings: male 26–29 (27.71.5), female 21–24 (22.52.1); pronotum: male 7–8 (7.7.6), female 7; tegmen: male 35–36 (35.7.6), female 35–36 (35.5.7); hind femur: male 21–22 (21.3.6), female 20; ovipositor: 8–9 (8.5.7) mm.

Material examined (19 specimens). Democratic Republic of Congo: Katanga, Kolwezi , (-10.7166667, 25.4725), ii.1953,coll.Gilbert— 1 female (paratype) ( BMNH) ; Mozambique: Sofala, Cheringoma, nr. Codzo ( Khodzue ), cave and nearby, elev. 216 m (-18.564, 34.872222), 14–25.iv.2017, coll. P. Naskrecki— 2 females ( EOWL) ; Gorongosa , GNP, Chitengo , E.O. Wilson Laboratory, elev. 48 m (-18.977722, 34.351333), 9.ii.–4.iii.2015, coll. P. Naskrecki and R. Guta— 1 male ; Gorongosa Dist., Archway Gorge , campsite, elev. 63 m (-18.95336, 34.61089), 22–29.iv.2013, coll. P. Naskrecki— 1 female ; Wilson Laboratory, GNP, Chitengo , (-18.97775, 34.351333), 19–28.ii.2017, coll. P. Naskrecki— 1 male ( EOWL) ; GNP, Chitengo , elev. 29 m (-18.98194, 34.35122), 17.iii.– 5.iv.2013, coll. P. Naskrecki— 1 female, 3 males ; same locality, 17–31.iii.2013, coll. P. Naskrecki— 1 male ; same locality, 30.i.–13.ii.2014, coll. P. Naskrecki— 2 males ( MCZ) ; Gorongosa Distr., Chitengo , (-18.981944, 34.351222), 2–28.ii.2015, coll. R. Guta— 1 male ; GRP, E.O. Wilson Lab Chitengo , (-18.9783, 34.3514), 9.ii.–4.iii.2015, coll. P. Naskrecki & R. Guta— 3 males ; same locality, 1–21.iv.2015, coll. P. Naskrecki & R. Guta— 1 male ( EOWL) ; Tanzania: Kilosa , iii.1926, coll. Miller— 1 male (holotype) ( BMNH) .

Figures

FIGURE 36. Mozambican Oxyecous spp.: A. Oxyecous lesnei, male right tegmen; B. ditto, male abdominal apex, dorsal view; C. ditto, male subgenital plate; D. ditto, male, lateral view; E. ditto, female, lateral view; F. ditto, ovipositor; G. ditto, male head and pronotum, dorsal view; H. O. magnus, male, lateral view; I. ditto, ovipositor; J. ditto, male head and pronotum, dorsal view; K. ditto, male abdominal apex, lateral view.

FIGURE 54. Oscillograms and power spectra of Mozambican Phaneropterinae: A–C. Gonatoxia helleri; D–F. Debrona cervina, stationary call; G–I. Oxyecous lesnei, stationary call; J–L. O. magnus.