A new genus of African Karniellina (Orthoptera, Tettigoniidae, Conocephalinae, Conocephalini): integrating morphological, molecular and bioacoustical data

Abstract

Melanoscirtes gen.n. is established within Karniellina. The members of this subtribe are small conocephaline bush crickets, confined to Africa. Melanoscirtes is erected on Phlesirtes kibonotensis, a species restricted to forest clearings and forest edge in the submontane and montane zones of Mt. Kilimanjaro. A subspecies, M. kibonotensis uguenoensis, is described from the North Pare mountains, a mountain range of the Eastern Arc adjacent to Mt. Kilimanjaro. Further species of Melanoscirtes occur on other mountain ranges of the northern branch of the Eastern Arc mountains of northern Tanzania and southern Kenya. The South Pare mountains harbour M. shengenae; the West Usambaras, M. usambarensis, and the Taita Hills, M. taitensis. All species and subspecies of Melanoscirtes exhibit a similar morphology and occupy analogous habitats on the respective mountains. The song patterns for all species found within this genus are very similar, and this, together with evidence from molecular data, suggests that allopatric speciation is the reason for the biogeographic pattern found in this genus. A key for the subspecies and species of Melanoscirtes is provided.

Broken bridges: The isolation of Kilimanjaro's ecosystem

“…The last period allowing a dense forest cover and the spread of flightless montane species could have been at the end of the African humid period about 4,000–5,000 years ago (Thompson et al., ), when a high peak in arboreal pollen and fern spores were found in palaeo soils on the northern slopes of Kilimanjaro (Montade et al., accepted). Based on the actual distribution pattern and ecological demands of Aerotegmina kilimandjarica , a flightless bushcricket in montane forests on most high mountains in northern Tanzania (including Meru and Kilimanjaro) up to the highlands of Kenya (Heller et al., ; Hemp, ,b,c; Hemp, Heller et al., ; Hemp, Kehl et al., ), we conclude that a corridor suitable for the migration of this montane forest species would require a lower or middle montane wet evergreen forest of Cassipourea or Ocotea type with a mean annual precipitation of at least 1,100–2,400 mm and a mean annual temperature of about 12–17°C (cp. Hemp, ), that is, 2–7°C cooler and 400–1,700 mm wetter than today in the area between Meru and Kilimanjaro.…”

“…Tropical mountains are not only hot spots of biodiversity and endemism (Körner & Spehn, ; Mittermeier, Turner, Larsen, Brooks, & Gascon, ; Myers, Mittermeiers, Mittermeier, da Fonseca, & Kent, ) but also evolutionary cradles, accumulating neo‐endemics as has been suggested for many tropical regions (Merckx et al., ) as well as on the East African mountains—particularly in their forest belts (Hemp, Kehl, Schultz, Wägele, & Hemp, ; Schwery et al., ). Climatic fluctuations on East African mountains over the past few 1–2 million years were the motor for the high biodiversity in Orthoptera in the area (Hemp, Grzywacz, Warchałowska‐Śliwa, & Hemp, ; Hemp, Kehl, Heller, Wägele, & Hemp, , ; Hemp, Heller et al., , ) connecting and isolating forest habitats and thus enabling a spread of forest dependent taxa or boosting speciation through isolation. During the last glacial maximum (LGM), East African vegetation now classed as montane was wider ranging at lower elevations (Schüler, Hemp, Zech, & Behling, ; Van Zinderen Bakker & Clark, ).…”

Environmental niche divergence between genetically distant lineages of an endangered water beetle

“…A practical yet conservative strategy adopted by many researchers has been to apply a diverse range of evidence to support the recognition of species (e.g. fixed or non‐overlapping differences in morphological, behavioural or ecological characteristics, molecular divergence thresholds, additional quantitative methods, or geographic isolation), thereby meeting the requirements of several species criteria (De Queiroz, 1998, 2007; Raxworthy et al ., 2007; Hemp et al ., 2010; Padial et al ., 2010; Tobias et al ., 2010). In this sense, decisions based on traditional morphological and genetic data alone can be problematic, especially if the hypotheses are contradictory; for examples of conflicts between morphology and phylogenetic history in water beetles, see Ribera, Bilton & Vogler (2003) and Hawlitschek et al .…”

Ecological adaptations of grassland‐inhabiting flightless Orthoptera: Fulvoscirtes and Acanthoscirtes, two new genera of African Karniellina (Orthoptera, Tettigoniidae, Conocephalinae, Conocephalini)

“…the pyrgomorphid genus Parasphena with about 25 species in eastern Africa (Hemp et al , 2009a), the lentulid genera Rhainopomma and Usambilla (Hemp et al , 2007; Schultz et al , 2007), the eumastacoid genus Chromothericles (Hemp, 2009b), or species of the recently erected genus Altihoratosphaga (Hemp et al , 2010a). However, the highest diversity is found within the subtribe Karniellina of Conocephalini with over 30 species distributed over East Africa (Hemp et al , 2010b, c). Genera and species of Karniellina described at present (excluding the new genera Fulvoscirtes and Acanthoscirtes ) are listed in Table S1.…”

“…Hemp et al (2010b) erected the genus Chortoscirtes (five species) on species confined to coastal grasslands and savannah habitats. Another well‐defined genus, Melanoscirtes (four species), is adapted to submontane and montane forest clearings in the area of the northern branch of the Eastern Arc mountains and Mt Kilimanjaro (Hemp et al , 2010c). In this paper we erect the genera Fulvoscirtes n.gen.…”