Arantia (Euarantia) rectifolia Brunner von Wattenwyl 1878

Arantia (Euarantia) rectifolia Brunner von Wattenwyl, 1878 (Figs. 19, 21, 22, 57, 88a, b)

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Brunner von Wattenwyl (1878). Monographie der Phaneropteriden, 137.

Type locality: EQUATORIAL GUINEA. Fernando Póo. Depository: NMW, Vienna. Kind of type: holotype male. Syn. Arantia (Euarantia) accrana Karsch, 1889

Karsch, 1889. Berlin Ent. Z., 32: 433, 436.

Type locality: GHANA. Accra. Depository: MfN, Berlin. Kind of type: holotype female.

Material examined. EQUATORIAL GUINEA. Fernando Póo (♂ holotype) (NMW). TOGO. Kpalimé, Ft of Missahohe 29–30.VII.2013 (light trap), P. Moretto (1♂). Fazao 3–4.VIII.2013 (light trap), P. Moretto (3♂). BURKINA FASO. Pama VIII.2005, P. Moretto (3♂). IVORY COAST. Boudoukou Zamou VII.2004, P. Moretto (3♂). Cornal VIII.1998, P. Moretto (1♂). Khorogo, Koko village 20.VII.2013, P. Moretto (3♂). Man, Mt. Tonkoui (1200m) 14–15.VII.2014 (light trap), P. Moretto (3♂); same locality 28.VI–1.VII.2014 (light trap), P. Moretto (3♂, 1♀); same locality 13–15.VII.2014 (light trap), P. Moretto (1♂); 18–20.VI.2015 (light trap), F. Moretto (2♂); same locality 24–28.VII.2015 (light trap), P. Moretto (1♂); same locality 4.VI.2016 (light trap), P. Moretto (1♂). Khorogo, Koko (347m) 31.VII.2014, dry forest (light trap), P. Moretto (3♂). Comoe, Kolomabira (347m) 20.VII.2013, P. Moretto (1♂). Comoe, Kolomabira (228m) 8.VI.2015 (light trap), P. Moretto (2♂); same locality 22.VI.2015 (light trap), P. Moretto (1♂). Comoe, Zamou (280 m) 27.VII.2016 (light trap), P. Moretto (2♂). Taï Nat. Park, Res. Station 18–21.III.2017 (light trap), B. Massa (11♂). Taï National Park, Res. Station 16.III.2017, platform 40m (light trap), B. Massa (1♂). Taï Nat. Park, Res. Station 2–4.IV.2017 (light trap), P. Moretto (5♂, 2♀) (BMCP). Taï Nat. Park, Res. Station 25.III.2017 (light trap at platform 40m), P. Annoyer (1♂) (PACT). Taï Nat. Park, Res. Station 5–10.VII.2015 (light trap), M. Aristophanous, P. Moretto, E. Ruzzier (1♂) (NHM). CENTRAL AFRICAN REPUBLIC. Dzanga-Ndoki National Park, Lac 2, 25.I.2012, 10–11.II.2012, 15–16.II.2012, 28– 29.II.2012, 24–25.II.2012 (6♂) (BMCP). Kaniana 15.II.1939, H.J. Brédo (1♂) Elisabethville (= Lubumbashi) 25.IV.1939, H.J. Brédo (1♂). GABON. N’Toum II.1983, 2.VII.1984, IV.1985, 15.VII.1985, 29.VII.1985, 15.VIII.1985, 15.IX.1985, 30. IX.1 986, A. Pauly (7♂, 1♀). DEMOCRATIC REPUBLIK CONGO. 23–27.II.1948, G.F. de Witte (1♂). Kaziba. N Kivu, Rwankwi 31.V.1961, Y.V. Leroy (1♂). CAMEROON. Akono I–II.1969 (1♂) (RBINS). KENYA Kakamega Forest Reserve, Buyango Hill 27.IX.2005, Holstein & Bartsch (1♂) (CHB).

Further material examined. A. accrana: GHANA. Accra, Ungar (♀ holotype). TOGO. Misahöhe 5– 15.IV.1894, Baumann (2♂) (MfN).

Measurements. Males. Body length: 26.8–30.0 (mean: 27.0); pronotum length: 5.9–6.5 (mean: 6.2); pronotum height: 6.7–7.1 (mean: 6.9); hind femur: 25.5–28.5 (mean: 27.0); hind tibia: 27.1–30.1 (mean: 28.5); tegmina length: 45.0–49.0 (mean: 47.5); tegmina width: 12.0–13.8 (mean: 12.8); length/tegmina width: 3.5–3.7; width tegmina/length pronotum: 2.0–2.1.

Measurements of the female holotype A. accrana. Body length: 24 mm; pronotum length: 7 mm; tegmina: 53 mm; tegmina width: 12.8; hind femur length: 28 mm; ovipositor: 5 mm (Karsch 1889).

Characters. A. rectifolia is a species of medium size [body length ♂ 26–30 mm; ♀ 27–32 mm; the size of the ♀ (47 mm) reported by Griffini (1908) is uncertain, because doubtfully identified]. Brunner von Wattenwyl (1878) described the male and considered it similar to A. fatidica. Later, both sexes were recorded by Karsch (1889), Brunner von Wattenwyl (1891) and Bruner (1920) from Lolodorf (Cameroon) and the Democratic Republic Congo. Ragge & Roy (1965) reported the species from Senegal, Ragge (1968b) from the Ivory Coast, and doubtfully Griffini (1908) from Mukonje Farm (Cameroon). Ebner (1943) recorded it again from Fernando Póo (Equatorial Guinea). The width of tegmina of the holotype is 12.8 mm, intermediate between Arantia and Euarantia, in other specimens examined it ranged between 12.0 to 13.8 mm. Hind tibiae are not as curved as it was given by Heller et al. (2014) for Euarantia.

Typical is an ivory-coloured coating mixed with some dark traces on the fore tibiae in the area of the tympana. The dorsal sides of the tympana are conchate while the ventral sides are oval and open. The tegmina are not very broad, with sometimes only faintly visible 4–5 ivory (in living specimens) or more tawny to orange spots (in preserved specimens, see Figs 19, 21, 22). The stridulatory file is short, curved and consists of 80–85 teeth (Fig. 57). The fore femora are unarmed or armed with 1–2 small spines ventrally. The hind femora are armed with 3–5 inner and 4–7 outer ventral black-tipped or black small spines. Male cerci are long and slightly sinuous and have a black, chitinous and rounded apex (Figs 88a, 88b). Subgenital plate with tiny styli, in many specimens absent.

Only the female of A. accrana was described by Karsch (1889) although 2 males are also present in the Berlin collection which Karsch himself identified as belonging to A. accrana in 1894 (examined; see Fig. 22). The comparison of material of the male holotype of A. rectifolia with the male identified by Karsch as A. accrana showed no differences between the two taxa. Also the female holotype of A. accrana was compared with females caught together with male A. rectifolia. No differences in size and shape of the ovipositor and subgenital plate could be detected. Brunner von Wattenwyl (1891) separated the taxa on base of the ventral spination of the fore femora (absent in accrana, present in rectifolia) and the presence of ivory spots on the anterior margin of the tegmina. The ivory spots are expressed mostly in males and also the spination varies between specimens checked from being tiny to absent. At that time only the female of A. accrana was described and stored in Berlin and the key of Brunner of Wattenwyl was based on Karsch´s description. For these reasons here A. accrana is considered synonymous with A. rectifolia.

Remarks. A. rectifolia shows some variation in the morphology of the stridulatory area. Probably A. rectifolia is a complex of closely related species. Only studies on songs and molecular analysis will help to clarify the status of this taxon.

Distribution. Probably widely distributed throughout West and Central Africa (records from Cameroon, Equatorial Guinea, Central African Republic, Democratic Republic Congo, Senegal, Togo, Burkina Faso, Ivory Coast).