Conocephalus iris Serville, 1838

Heller, Klaus-Gerhard, 2019, Provisional checklist of the Tettigonioidea (Insecta: Orthoptera) from São Tomé & Príncipe with taxonomic remarks, bioacoustical data and the description of new taxa, Zootaxa 4563 (1), pp. 41-66 : 51-52

Conocephalus iris Serville, 1838

Xiphidion guineensis Redtenbacher, 1891 syn. n.

Xiphidion africanum Redtenbacher, 1891 syn. n.

Conocephalus inaequalis Uvarov, 1928 syn. n

1 male, SAO TOME & PRINCIPE: São Tomé, Roca Monte Forte near Neves (0°20'N, 6°32'E), 100 m a.s.l., 22 iv 2018, leg. Martina & K.- G. Heller ( CH 8577; length of tegmen 5.5 mm, of hind wing 4 mm) ; 1 male, SAO TOME & PRINCIPE: Príncipe, near Bom Bom Island Resort (1°41'N, 7°24'E), 20 m a.s.l., 24–27 iv 2018, leg. K.- G. Heller & Marianne Volleth (collected as nymph) ( CH 8578; length of tegmen 4.5 mm, of hind wing 2.5 mm) .

New record for São Tomé and Príncipe. Material used for comparison (in collection Hemp): male, TANZANIA, H5232, 3.2009, 1240m, leg. C. Hemp, length of tegmen 19 mm, of hind wing 20.5 mm, cerci Fig. 8 A ; male, TANZANIA, Tarangire, Auwald, 5/15, leg. C. Hemp, length of tegmen 17 mm, of hind wing 20.5 mm; 2 males, TANZANIA, Babati, Darakuta Ranch, 1250m, Wiese 5/17, leg. C. Hemp, male 1: length of tegmen 11 mm, of hind wing 11 mm, cerci Fig. 8 B , male 2: length of tegmen 7 mm, of hind wing 6.5 mm; male, UGANDA, Mt. Elgon, bei Budadiri, 1250m, Plantagenzone, leg. C. Hemp, length of tegmen 9.5 mm.

Using the keys in Redtenbacher (1891) and Karny (1907), our animals could be identified as belonging to C. guineensis . The short-winged species ( Fig. 5 B ) is easily recognizable by the large number of spines on the lower side of front tibia (10–11 in each row compared to 6–7 in other species; Redtenbacher 1891). The cerci have a characteristic bispinate shape ( Fig. 8 C ), identical in both males. The two spines are not situated in the same plane, but the proximate smaller is directed more upwards ( Fig. 8 A–C). The fastigium verticis is nearly as wide as the scapus ( Fig. 8 D ). The prosternum is armed with two spines as already described by Karny (1907). The stridulatory vein is equipped with about 30 teeth ( Fig. 8 E ).

Because of the unusual tibial armature Karny (1912) considered C. guineensis as member of the subgenus Palotta Walker , a name listed by Harz (1969b) as a synonym of Conocephalus at generic level without discussing subgeneric relationships. It was synonymized and removed as subgenus by Otte (1997) without comments. This action may have been justified since the holotype of Palotta inornata Walker, 1869 , the type species of Palotta , seems to be a nymph of Thyridorhoptrum Rehn & Hebard ( Pitkin 1977) . The three African species C. iris , africanus and guineensis , formerly included in Palotta , are not only very similar to each other in all aspects including cercus shape ( Fig. 8 A–C) except tegmen length ( Bruner 1920), but they occur also occasionally sympatrically ( Bruner 1920). In Tanzania long and short winged specimens are considered as wing morphs of C. iris (Hemp in prep), as it seems also to have been done by Bazelet & Naskrecki (2014, with photo of short-winged form called C. iris ). Variability in wing length is well known for several Conocephalus species (especially for C. dorsalis , see e.g. Harz 1969b, but also for C. fuscus in Ando & Hartley 1982 , C. japonicus in Higaki & Ando 2003 , C. bambusanus according to photos in OSFO; variation in wing length already mentioned by Bruner 1891, p. 59, and later by Pitkin 1980, p. 321, for several species). We follow the proposal of Hemp (in prep) and consider C. iris as a species polymorphic in wing length with the named varieties guineensis Redtenbacher, 1891 for the micropterous and africanus Redtenbacher, 1891 (obviously known only from two females; Redtenbacher 1891, Bruner 1920) for the brachypterous form (terms used according Harz 1969b, p. xii–xviii). As to expect, the song of the form guineensis is also very similar to that of the typical form (see below, B). The short-winged Conocephalus inaequalis Uvarov, 1928 , known from two males ( Uvarov 1928, Heller et al. 2014), has the same cercus shape as the other forms. The male from Congo has also the unusual tibial armature, while in the type only remainings of one fore leg exit. Uvarov (1928) does not discuss any similarities or relations to the species mentioned above. Therefore we assume that C. inaequalis is only another name for a short-winged form of C. iris and has to be synonymized.

The form guineensis is relatively widespread in West and West Central Africa (from Senegal ( Ragge & Roy 1961) to Cameroon ( Bruner 1920), Democratic Republic of Congo ( Griffini 1908, 1909), the island of Bioko ( Fernando Poo; Bolivar 1906), to Gabon (type locality) and South Africa, while the range of the nominate form iris is even larger (see Bazelet & Naskrecki 2014). From the island of Mauritius the typical long-winged form is known ( Stal 1861).

On both archipelagos of São Tomé and Príncipe, Burr (1927) noted a long- and a short-winged species of Conocephalus (as Xiphidium ), the latter now being considered as C. iris var. guineensis . The long-winged form may mostly have been C. conocephalus .

Using more recent studies ( Otte 1997, OSFO), however, it would not be possible to confirm this identification of C. guineensis / iris . Here C. iris and guineensis are assumed to belong to the subgenus Conocephalus characterized by an unarmed prosternum. After a closer look it turned out that Otto (1997) mixed up the species of the different subgenera of Conocephalus especially concerning the placement in the subgenus Conocephalus . The resulting confusion was never corrected (OSFO 18 May 2018). So we studied older revisions (e.g. Karny 1907, Rehn & Hebard 1915, Uvarov 1928, Pitkin 1980), and/or the descriptions of the species listed at present in the subgenus Conocephalus according to OSFO and transferred the species with armed prosternum to Anisoptera (see below). An unarmed prosternum is the key character of Conocephalus (Conocephalus) (see e.g., Karny 1912, Harz 1969a, b). These remaining "true" Conocephalus (Conocephalus) are also listed below. From the group of species formerly included in C. ( Conocephalus ) and now not assignable to subgenera (see below), most species have tegmina much longer than the pronotum, have been described before 1870 and were considered as doubtful species by Karny (1912).

Species listed erroneously as Conocephalus , subgenus Conocephalus in OSFO (5 May 2018) and herewith transferred to subgenus Anisoptera (references fide OSFO, not all checked)

aigialus Rehn & Hebard, 1915 , angustivertex Pitkin, 1980 , armatipes ( Karsch, 1893) , attenuatus ( Scudder, 1869) , bidentatus Shi & Zheng, 1994 , brevipennis ( Scudder, 1862) , caudalis ( Walker, 1869) , chavesi ( Bolívar, 1905a) , cognatus ( Redtenbacher, 1891) , doryphorus ( Karny, 1907) , ebneri Harz, 1966 , exitiosus ( McNeill, 1901) , fulmeki ( Ebner, 1927) , gracillimus Morse, 1901 , hygrophilus Rehn & Hebard, 1915 , inconspicuus ( Karny, 1920), infumatus ( Redtenbacher, 1891) , kisi Harz, 1967 , meadowsae Harz, 1970 , nemoralis ( Scudder, 1875) , nigropleuroides Fox, 1912 , nigropleurum ( Bruner, 1891) , occidentalis ( Morse, 1901) , peringueyi Uvarov, 1928 , recticaudus Bruner, 1915 , redtenbacheri ( Bolívar, 1905b) , resinus (Saussure & Pictet, 1898) , spartinae ( Fox, 1912) , trivittatus ( Stål, 1861) , tumidus Pitkin, 1980 , tumultuosus Willemse, 1942 , willemsei Pitkin, 1980 .

Species listed erroneously as Conocephalus , subgenus Conocephalus in OSFO (5 May 2018) and herewith left unassignable to subgenus level (see above)

amabilis ( Stål, 1861) , posticus ( Walker, 1869) , punctipennis ( Walker, 1869) , tenellus ( Walker, 1869) , tenuis ( Walker, 1869) , hecticus ( Gerstaecker, 1869) , stramineus ( Haan, 1843) , cercorum Sjöstedt, 1926 (photo in OSFO: holotype is a male nymph). Also C. grebenchikovi Uvarov, 1942 is placed here, because it is very similar to C. kisi ( Willemse et al. 2016, 2018) but is described as missing the prosternal spines. The type and single known specimen, however, seems to be missing ( Harz 1969b).

Complete list of species of Conocephalus , subgenus Conocephalus , based on OSFO (5 May 2018)

bambusanus Ingrisch, 1990 (including abispinatus Xia & Liu, 1992 ; syn. of bambusanus according Liu & Zhang 2007, Zhou et al. 2010), basutoanus Chopard, 1955 , bispinatus Pitkin, 1980 , brevivalvus ( Shi, Wang & Fu, 2005) , brincki Chopard, 1955 , conocephalus ( Linnaeus, 1767) , differentus Shi & Liang, 1997 , emeiensis Shi & Zheng, 1999 , lugubris ( Redtenbacher, 1891) , obtectus Karny, 1907 , saltans ( Scudder, 1872) , somali (Burr in Peel et al., 1900) , sulcifrontis Xia & Liu, 1992 , tridens Hebard, 1933 , xiai Liu & Zhang, 2007 .

Figures

FIGURE 5. Habitus. A Adapantus excavatus n. sp., B Conocephalus iris, var. guineensis, C Brachyamytta bombomensis n. sp.

FIGURE 8. Morphological details of Conocephalinae. A–E male Conocephalus iris, A cercus of typical long winged form, B cercus of brachypterous variety africanus, C cercus of micropterous variety guineensis, D fastigium, E stridulatory file and left mirror cell. F–G Stridulatory files of Ruspolia, F R. differens, G R. fuscopunctata. Scale 1 mm.