Coryphosima danieli Massa

Felix, Rob P. W. H. & Massa, Bruno, 2016, Orthoptera (Insecta: Tettigonioidea, Pyrgomorphoidea, Acridoidea) of Kafa Biosphere Reserve, Bale Mountains National Park and other areas of conservation interest in Ethiopia, Zootaxa 4189 (1), pp. 1-59 : 47-49

Coryphosima danieli Massa n. sp.

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:492582 Figure 40

Material examined. ETHIOPIA: Oromia, Bale, Bale Mountain Lodge , Bale Mountains N.P. (2380 m) (light), 13– 15.XII.2015, B. Massa, A. Carapezza and D. Wiersbowsky (1Ƌ holotype, 1♀ allotype, 1Ƌ, 1♀ paratypes) ( BMPC).

Description. Colour. Green and dark brown, with contrasting darker colour on sides than on upper part of head, pronotum and tegmina. Hind femora darker apically, hind tibiae with darker base.

Male. Antennae nearly longer than head and pronotum together, the first 7–8 segments flattened, others rounded. Foveolae absent. Face oblique, frontal ridge with parallel margins, except near the ocellus, where it is narrowed. Fronto-genal carinae evident. Fastigium of vertex parabolic, prominent, 1.1 times longer than broad, its surface concave, margins smooth.

Pronotum disc slightly tectiform, with irregular longitudinal rugosities, central carina raised, interrupted only by typical sulcus, prozona just longer than metazona. Lateral carinae parallel, lower than central carina, broader and flattened in metazona. Anterior margin of pronotum nearly straight, posterior rounded. Lateral lobes as long as deep, their surface rugulose, lower margin little ascendant. Mesosternal space as long as wide, metasternal space much smaller, nearly square.

Tegmina just exceeding the 3rd abdominal tergite, reaching about 1/3 of hind femur, pointed apically. Veins distinct and straight, except costal margin, where they are rounded above tympanum. Hind wings shorter than tegmina, reduced only to narrow appendices unable to fly.

Abdominal tergites with a central small carina, epiproct longer than large, concave. Cerci narrow, conical and slightly in-curved. Subgenital plate stout. Epiphallus typical for the genus ( Dirsh 1965).

Female. As the male with the following differences. Antennae not reaching hind margin of pronotum, fastigium of vertex as long as broad, lateral carinae on metazona obsolete, tegmina not exceeding the 3rd abdominal tergite, reaching about ¼ of hind femur, cerci stout, conical, ovipositor valves stout.

Measurements. Males. Body length: 12.3–13.2; Pronotum length: 1.8–2.0; Length of hind femur: 7.5–8.0; Length of tegmina: 4.6–5.0. Females. Body length: 16.5–18.0; Pronotum length: 2.7–2.8; Length of hind femur: 10.2–10.5; Length of tegmina: 6.1–6.4. Body/Tegmina length: males 2.6–2.7, females 2.7–2.8.

Diagnosis. It is one of the smallest known Coryphosima species, characterized by very short tegmina.

Affinities. It is a very small species, probably derived from the stenoptera group, which has evolved in the isolation of plateau grasslands, adjacent to forests of Bale Mts. Dirsh (1966) considered the short-winged species of Coryphosima not exceeding the range of individual variability, and so near to C. stenoptera that it was quite possible they are only brachypterous forms of that species. Jago (1970) was of a different opinion and listed seven brachypterous species as belonging to the genus Coryphosima , living in the highlands of Ethiopia [Wouramboulki near Djem-Djem: abyssinica ( Uvarov 1934) ], Uganda [Mt. Elgon: elgonensis ( Uvarov 1930) ], Tanzania ( cytidonota Jago 1970 ), Zimbabwe (Vumba Mts: vumbaensis Miller 1949 ), Guinea (Mt. Nimba: nimbana Chopard 1958 ), highlands of Mali ( maliensis Descamps 1965 ) and Sierra Leone ( bintumana Roy 1964 ).

C. danieli n. sp. is the most brachypterous species of the genus, with tegmina very modified, shorter and wider than in other related species. Differences from C. stenoptera are evident, in particular the bigger size, the straighter shape of costal area of tegmina and longer antenna and tegmina of the latter. Differences from the East African brachypterous species are the following: C. abyssinica has bigger size, antennae considerably longer than head and pronotum together, fastigium of vertex much longer than broad and with a faint transverse sulcus, pronotal longitudinal rugosities only in metazona, tegmina proportionally longer (Body/Tegmina length: male 2.4, female 2.6) and a paler stripe along the lower half of head and pronotal lobes ( Uvarov 1934). Tanzanian C. cytidonota has lateral pronotal carinae complete also in metazona (in males), longer tegmina and hind wings (Body/Tegmina length: male 2.1, female 2.4) ( Jago 1970). Ugandan C. elgonensis also has tegmina longer than C. danieli n. sp., reaching the middle of hind femora (Body/Tegmina length: male 2.4, female 2.5), and hind wings shorter than tegmina (in C. danieli n. sp. they are atrophic) ( Uvarov 1930), like C. vumbaensis (Body/Tegmina length: male 2.1, female 2.0), C. nimbana (Body/Tegmina length: male 2.4, female 2.1), C. bintumana and C. maliensis (Body/ Tegmina length: male 2.4, female 2.5).

Habitat. C. danieli n. sp. has been found in the grasslands adjacent to Harenna forest Lodge (Bale Mts); 3 individuals were caught in the night at light, another one in the day by net sweeping.

Remarks. According to Dirsh (1966) all brachypterous species are synonyms of C. stenoptera because they all occur at high elevations. In our opinion their isolation on high mountains is a valuable argument to treat them as separated species, with their wing shortness probably being a result of convergence; other morphological differences should confirm this.

According to Hemp et al. (2015), forest expansion during humid periods and retraction during dry periods explain the pattern of geographical species distribution found on East African mountains. During dry and warm periods taxa trapped in montane habitats later adapted to the montane climate or went extinct.

Along the slopes of high mountains of tropical East Africa ( Ethiopia, Kenya, Tanzania and Uganda), the vegetation is divided into three altitudinal zones: the afro-montane zone, the sub-alpine ericaceous zone and the afro-alpine zone. Endemism is high in the afro-alpine flora (80% at the species level), indicating that this flora has long been isolated from other high mountain or temperate floras ( Hedberg 1969). It is likely that the Pleistocene climatic changes have played an important role for the dispersal among mountain tops. Most of them are of volcanic origin, some Ethiopian mountains are part of quite extensive highlands, but the southern ones (like Bale Mts) consist mainly of isolated peaks emerging from the Great Rift Valley. During glaciations in the northern Hemisphere, the African tropics were cooler and drier ( Bonnefille et al. 1990). While the tops of many mountains were covered by glaciers, both the afro-alpine and the ericaceous zone extended about 1000–1500 m lower than today and thus occupied considerably larger areas ( Gottelli et al. 2004), the Ethiopian highlands were covered by afro-alpine heaths and grassland ( Messerli et al. 1977), and provided habitat for endemic species. Also in the mountain massifs of tropical East Africa, afro-alpine populations may have increased, while distances among habitat patches became smaller during the cool periods of the Pleistocene, facilitating dispersal from one mountain to another.

The importance of the Great Rift Valley as a phylogeographic barrier has been repeatedly documented for animals and phytogeographic studies (e.g. Gottelli et al. 2004). Following Yalden & Largen (1992) high-altitude grassland reached the highest parts of the floor of the Rift Valley at some time during the Pleistocene, when the afro-alpine vegetation belt was 1000–1500 m lower during cooler periods. Many insect species might be remained isolated on top of these volcanic peaks and did not have more relationships with their relatives. This could be the case of mountain short winged Coryphosima and other short winged Orthoptera here listed.

Etymology. This species is dedicated to Daniel Wiersbowsky, who organized the Ethiopian Insects Project and guided the entomological expeditions to Ethiopia with great professionalism.