Arantia (Euarantia) excelsior Karsch, 1889

Hemp, Claudia & Massa, Bruno, 2017, Review of the African genera Arantia Stål and Goetia Karsch (Orthoptera: Tettigoniidae: Phaneropterinae), Zootaxa 4362 (4), pp. 451-498 : 482-483

Arantia (Euarantia) excelsior Karsch, 1889 (Figs. 34–37, 39–40, 64, 96–98)

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:464787

Karsch (1889). Berlin Ent. Z., 32: 434–435.

Type locality: SIERRA LEONE. Depository: MZPW, Warsaw. Kind of type: holotype male. Syn. Arantia (Euarantia) mammisignum Karsch, 1896

Karsch (1896). Stett. Entomol. Z. 57: 332.

Type locality: CAMEROON. Lolodorf. Depository: MfN, Berlin. Kind of type: holotype female. Syn. Arantia (Euarantia) tigrina Bolivar, 1906

Bolívar I. (1906), Mem. Soc. espan. Hist. nat. 1: 330.

Type locality: EQUATORIAL GUINEA. Bioko ( Fernando Póo). Depository: MNCN, Madrid. Kind of type: holotype male.

Material examined. SIERRA LEONE. A. excelsior (♂ holotype images on OSF, Cigliano et al. 2017, MZPW, Warsaw). (1♂, 1♀) ( MNCN) . CAMEROON. Kiroi 1908, S. Lamey (1♀) ( MSNG) . CENTRAL AFRICAN REPUBLIC. Dzanga-Ndoki National Park, Ndoki 26.I.2012; Border of Lac 1 , 13–14.II.2012. Lac 1, 24–25.II.2012 (light trap), P. Moretto (5♂). IVORY COAST. Taï Nat. Park , Res. Station 20–22.III.2017 (light trap), B. Massa (6♂) ( BMCP) . Taï National Park , Res. Station 5–10.VII.2015 (light trap), M. Aristophanous, P. Moretto, E. Ruzzier (5♂). Man, Mt. Tonkoui (1171m) 12–18.VII.2015 (light trap), M. Aristophanous, P. Moretto, E. Ruzzier (7♂). Telo Village (415m) 10–13.XI.2015 (light trap), M. Aristophanous, P. Moretto, E. Ruzzier (1♀) ( NHM) . Taï Nat. Park , Res. Station 25.III.2017 (light trap on platform at 40m), P. Annoyer (2♂). Taï Nat. Park, Res. Station 25.III.2017 (light trap), P. Annoyer (1♂) ( PACT) . GABON. N’Toum 19.XI.1982, V.1985 , 16.IX.1985, A. Pauly (3♂) ( RBINS) . A. tigrina : EQUATORIAL GUINEA . Fernando Póo ( Bioko ) (♂ holotype) ( MNCN) . CAMEROON. Dibongo , (♀ paratype) ( MNCN) . A. mammisignum : CAMEROON. Lolodorf (♀ holotype) ( MfN) .

Measurements. Body length: 33.8±1.3; pronotum length: 8.3±0.3; pronotum height: 9.3±0.2; hind femur: 28.4±1.3; hind tibiae: 33.6±0.4; tegmina: 57.5±1.4 (♀ holotype: 68.4); tegmina width: 15–21; tegmina length/ width: 2.7–3.2 (♀ holotype: 3.2); tegmina width/pronotum length: 1.9–2.1.

Characters. Karsch (1896) described A. excelsior on a single male from Sierra Leone (Fig. 34). A few years later he described A. mammisignum on a single female from Cameroon (Fig. 37). The most conspicuous characters of A. mammisignum are the two shiny white patches on the posterior part of the pronotum, and black markings on the fore margin of the tegmina. Obviously because of the conspicuous two white patches on the posterior pronotum Karsch did not realize that the newly described female was conspecific with A. excelsior . However, also the male shows this conspicuous character of white patches on the posterior margin of the pronotum, as well as black markings on the tegmina ( Figs 39–40 ). Now more specimens became available for study and it became obvious that A. mammisignum is conspecific with A. excelsior . Collections of MNCN hold a specimen from southern Cameroon (Dibongo) identified as A. tigrina , which is almost identical with the female of A. mammisignum including the colour pattern of the two large white patches on the posterior margin of the pronotum. The male holotype of A. tigrina (Fig. 36) has the same genitalic morphology as A. excelsior : the male cerci are stout at their base tapering to the apex, are sinuous midway and end in a dark coloured club (compare Figs 96, 97, 98 ). The male subgenital plate is very distinctive being elongate, almost rectangular and very narrow without styli but blunt short processes. Also the costal area of the tegmina has brown to black markings both in the A. excelsior and the A. tigrina types. In specimens studied the metazona of the pronotum is often brown with a whitish area at the posterior margin. Two large white patches may be present on the posterior pronotum (holotype A. mammisignum , female paratype A. tigrina ), may cover the whole posterior down-curved part of the pronotum (holotype A. tigrina ) or may be restricted to the immediate margin (holotype A. excelsior ). Typical is also a strong deflection of the pronotal disc in the area of the metazona ( Fig. 39 ). The face of the holotype in A. excelsior is reddish brown while it is ivory white in A. tigrina ; the face of the female of A. tigrina in MNCN is uniformly brown. Therefore, colour variation is apparent in this species as has also observed e.g. in specimens of A. fasciata from East Africa, as well as differences in body size. Some specimens of A. excelsior have blackish stripes on the legs (including the tympana of the fore tibia). Thus, both A. tigrina and A. mammisignum are here synonymized with A. excelsior . The stridulatory file of A. excelsior is short and broad and consists of ca. 65 more evenly spaced teeth ( Fig. 64 ). Further, some specimens (from Ivory Coast) have both inner and outer tympana closed on the fore tibia.

Affinities. A. excelsior is closely related to A. rectifolia and A. regina having a similar habitus of broad leaflike wings and similar male genitalia. A. rectifolia has tegmina less broad than A. excelsior and A. regina . In addition, in A. regina the male cerci are more slender and the club at the tips of the cerci is not as large as in A. excelsior . The female ovipositor is smaller in A. rectifolia . Also A. rectifolia lacks the brown-black patches at the anterior margin of the tegmina which seem typical for A. excelsior (Fig. 34). Another striking difference is seen on the metazona of the pronotum. In A. excelsior a conspicuous deflection is present while in A. rectifolia and in A. regina the posterior part of the metazona is only shallowly bent.

Distribution. Central and West Africa (records from Sierra Leone, Equatorial Guinea, Central African Republic and Cameroon).

Figures

FIGURES 39–44. Dorsal view of the pronotum and stridulatory area of tegmina (left) and lateral view of head, pronotum and base of tegmina (right) of Arantia (Euarantia) excelsior (39, 40), A. (Euarantia) scurra (41, 42) and A. (Euarantia) tibiaspinosa n. sp. (43, 44).

FIGURES 96–105. Cerci of Arantia excelsior (96, 97), Arantia tigrina (= A. excelsior) (98), Arantia scurra (99), Arantia tibiaspinosa n. sp. (100), Arantia griffinii n. sp. (101), Arantia dimidiata (102), Arantia gestri (= A. dimidiata) (103), Arantia galbana (104)and Arantia purpurea (105).

FIGURES63–71.Stridulatory files of Arantia retinervis (63), Arantia excelsior (64), Arantia scurra(65), Arantia tibiaspinosa n. sp.(66), Arantia griffinii n. sp. (67), Arantia bispinosa n. sp.(68), Arantia galbana (69), Arantia dimidiata (70) and Arantia purpurea (71).