The name Poreuomena is probably derived from the Greek verb Πορεύω meaning “bringing something into a definite direction”. The name Cestromoecha is probably derived from Κέστρον, an instrument used in pyrography (drawing by means of heat), pointed on one side and rounded on the other. The same name was used by the Macedonians to indicate a particular type of arrow; the word indicates something that has the form of κέστρον (κέστρον μοι έχειν).

Brunner von Wattenwyl (1878) erected the group Poreuomenae and the genus on the single species Poreuomena africana from Gabon, the only species known in this group at that time. Brunner von Wattenwyl (1878) noted that the new genus is similar in habitus to the genus Phaneroptera. Regarding differences to Phaneroptera both sides of the tympanal organs are closed in Poreuomena (not true for all newly-described species though, see below) while they are open in Phaneroptera. Furthermore, the fore tibiae are smooth without any furrow at their dorsal sides and completely unarmed. These characters differentiate the Poreuomenini from Phaneropterini and place them near to the Holochlorini (formerly divided into Holochlorae and Psyrae). Since Poreuomena was erected on the species africana generic characters were the 10^th abdominal tergite of the males being extended in two lobes and the Rs vein branching off near the base of the tegmen.

Karsch (1890) described Poreuomena tenuipes but erected a few years later his own genus on this species (Karsch 1896). The differentiating character for the two genera as given by Karsch (1896) was a bilobed 10^th male tergite in Poreuomena and an undifferentiated 10^th tergite in Cestromoecha. Further Karsch noted that the first side vein of the radius (Rs) typically branches off near the base in Poreuomena but more in or behind the middle in Cestromoecha (Figs 1, 2). Comparing all species we found that a further typical character of Poreuomena is flaps on both tegmina – both with stridulatory files on the underside (Figs 6–8). A flap and very likely convergently-evolved similar structure is only found in the East African endemic Ectomoptera Ragge, 1980 that has, however, a well-developed mirror on the right tegmen, while in Poreuomena a mirror is lacking completely. On the right tegmen only a reduced stridulatory file is found in Ectomoptera (for a review of stridulatory files on the right tegmen of Ensifera see Leroy 1970 or Chamorro-Rengifo et al. 2014). Table 1 shows a compilation of characters for species of the two genera Poreuomena and Cestromoecha with respective taxonomic changes.

Figures 1–5. 

Venation of Poreuomenini. Arrows point at Rs branching of from the radius 1. Rs branching off after the middle in Cestromoecha tenuipes. 2. Rs branching off basally, for example, in Poreuomena africana. 3–5. Mirror area of Cestromoecha tenuipes lacking the flaps on both tegmina bases, but with a well-developed mirror on the right tegmen (arrows). 5. Mirror area of Cestromoecha tenuipes from the underside with a well-developed stridulatory file, typical for all Poreuomenini.

Referring to the type species of Poreuomena, P. africana, and Cestromoecha, C. tenuipes, several species are currently misplaced and are here transferred to their respective genus on grounds of generic characters given above and below. A very obvious distinguishing character on generic level is the presence (Poreuomena africana) or absence (Cestromoecha tenuipes) of a mirror on the right side of the tegmen (Figs 3–5) – as well as the well-developed flaps with the stridulatory files on the underside in Poreuomena (Figs 6–8). Cestromoecha either has, at most, a small bulge on the left tegmen and a separate flap with a stridulatory file on the underside on the right wing but a well-developed mirror.

Figures 6–8. 

Tegminal flaps at the bases of the tegmina, here in Poreuomena tshuapa sp. nov., a generic character for the genus Poreuomena.

Karsch (1896) noted that he could not decide whether Poreuomena crassipes, described by him on a single female, also belonged to the new genus Cestromoecha or not since the male was unknown. Ragge (1968) in his index-catalogue of African Phaneropterinae listed the latter species under Cestromoecha without giving reasons for this change. Massa (2013) described the male of C. crassipes leaving it with Cestromoecha, although having a bilobed 10^th tergite and tegminal flaps typical for Poreuomena. Poreuomena magnicerca transferred by us from Cestromoecha, has typical tegminal flaps, a Rs branching off from the radius near the base of the tegmen, however, for Poreuomena, with an untypical, undifferentiated and thus not bilobed 10^th abdominal tergite. All other known Poreuomena species, including the here newly-described species have tegminal flaps on both tegmina, except for P. matthaei sp. nov. with a bulge at the right base of the tegmen. A flap is here defined as elongated and narrow, mostly pointed structure at the base of the tegmina, while a bulge is a broad and not pointed structure. Further, Poreuomena species have a Rs branching off from the radius near the base and a 10^th abdominal tergite derived from a bilobed basic structure (elongated bulges or with short or long, straight or downcurved lateral processes). Two species remain in Cestromoecha, C. tenuipes (syn. C. mundamensis) and C. longicerca, both having mirrors on the right side of the tegmen and no tegminal flaps (Figs 10, 12, 17).

Medium-sized, predominantly green, typical Phaneropterinae with narrow and elongate tegmina surpassed at their apices by the alae. Fastigium verticis smaller than the width of the scapus; triangular with rounded apex, shallowly sulcate, separated from conical fastigium frontis by a gap. Antennal sockets elevated beside fastigia. Fore coxa with a spine. Fore and mid femora dorsally rounded, ventrally with very tiny spinules. Hind femora slender, slightly thickened in basal part, with few tiny spinules along the ventral length. Fore tibiae very slender, thickened in the area of the tympana and slightly sulcate dorsally; tympana open on the inner, conchate on the outer side. Hind tibiae triangular or narrow rectangular in diameter, densely packed along each edge with slender spines; dorsally with a pair of tiny spurs on each side, ventrally with each one larger spur on each side. Left tegmen of typical Phaneropterine shape, with a slight bulge where the stridulatory file is located at the underside (Figs 10, 17). The right tegmen with a well-developed mirror (Figs 3, 5). Male 10^th abdominal tergite either flap-like or stout (Figs 13, 14, 20). Cerci from stout to long, slender and pointed; subgenital plate deeply bilobate; without styli (Figs 15, 21).

Central African Republic, Dzanga-Ndoki National Park, Lake 1, UV trap, 11–12.II.2012 (holotype ♂); same data 20–23.II.2012 (paratype ♂) (BMCP); Central African Republic, Dzanga-Ndoki NP, Saline des Buffles, 25.I.2012 (1♂); Mboki, 25–26.I.2012 (light) (1♂); Lake 1, 14–15.II.2012, 19–20.II.2012 (light) (3♂) (PAPC). Gabon, Mikongo (Rougier), Mts de Cristal (secondary forest) (430 m alt.) 28.VII-12.VIII.2019 (MV Light Trap) (1♂) (ANHRT).

The stridulatory area of the left tegmen is short; it is slightly arched and has ca. 30 evenly-spaced teeth (Fig. 11). The right tegmen has a mirror (Fig. 10). The cerci are strongly curved downwards at their bases, with their inner parts concave, sharply bent upwards and becoming narrower with pointed tips (Figs 13, 14). The subgenital plate is triangular, narrowing to its apex, divided into two long and acute lobes (Fig. 15).

Green-brownish, tegmina green with a black marking on the stridulatory area (Figs 9, 10), black spots on the posterior margin of tegmina, 3–4 small yellow spots on the centre of the tegmina. Some small reddish spots are present on the pronotum.

(mm). Males. Body length: 15.7–16.0; Pronotum length: 4.0–4.2; Pronotum height: 3.5–3.7; Length of hind femora: 17.4–17.5; Length of tegmina: 25.8–28.2.

The cerci of the male have a very stout base, with the inner part concave bending sharply upwards and becoming very narrow; the cerci surpass clearly the 10^th tergite and the apices are very pointed (Figs 13, 14).

Dzanga-Ndoki National Park (Central African Republic) (Massa 2013, Massa et al. 2020), and Mts de Cristal (Gabon) (Massa, in press).

Figures 9–15. 

Morphological details of male Cestromoecha longicerca. Habitus (9). Stridulatory area with mirror on right tegmen (10), stridulatory file on the underside of the left tegmen (11), close-up of mirror (12), abdominal apex in lateral view (13), rear view (14) and subgenital plate (15).

Cameroon, Barombi Station (2♀ syntypes) (MfN); Cameroon (1♀) (MCNM); Cameroon, Mundame (1♂, 2♀) (NHMW); Angola (1♀); Equatorial Guinea, Fernando Poo (1♂);

Equatorial Guinea, Fernando Poo, Musolo I. 1902, L. Fea (1♂, 1♀); Fernando Poo, Basile (1♀) (MSNG); Cameroon, Campo Ma’an National Park (lowland rainforest) (950 m alt.) 10–22. III. 2018 (MV Light Trap), Fotsing, Ishmael, Miles, Safian (1♂) (ANHRT); Central African Republic, Dzanga-Ndoki NP, Lake 1, 30–31. I. 2012, 11–12. II. 2012, 21–22. II. 2012 (light) (3♂) (BMPC & PAPC).

Sjöstedt (1912) stated that Griffini (1905/6) found no differences between C. tenuipes and C. mundamensis, both described by Karsch. Sjöstedt mentions that a generic character on which Cestromoecha was erected, is a missing mirror on the right tegmen, while C. mundamensis has a well-developed mirror. However, both C. tenuipes (Fig. 17) and C. mundamensis males have well-developed mirrors and a comparison of the outer genitalic system of both C. tenuipes (Figs 19–21) and C. mundamensis showed no differences. Therefore, we suggest to synonymize both species that also have an overlapping distribution pattern to be synonymised.

Central to West Africa.

Figures 16–21. 

Morphological details of male Cestromoecha tenuipes. Habitus (16), stridulatory area (17), stridulatory file on the underside of the left tegmen (18), abdominal apex in lateral (19) and dorsal view (20) and subgenital plate (21).

Medium-sized, predominantly green typical Phaneropterinae with narrow and elongate tegmina surpassed at their apices by the alae. Fastigium verticis smaller than the width of the scapus; triangular and sulcate above, separated from the conical fastigium frontis by a gap. Antennal sockets elevated beside fastigia. Fore coxa with a spine. Fore and mid femora dorsally rounded, ventrally with very tiny spinules. Hind femora slender, slightly thickened in basal part, with few tiny spinules along the ventral length. Fore tibiae very slender, thickened in the area of the tympana and sulcate dorsally; tympana open on inner, conchate on outer side. Hind tibiae triangular or narrow rectangular in diameter, densely packed along each edge with slender spines; dorsally with a pair of tiny spurs on each side, ventrally with one larger spur on each side. Bases of the tegmina differentiated into flaps; on each of these flaps, a similar shaped stridulatory file on the underside is present. No mirror developed on the right tegmen. Rs vein branching off from the radius basally. Male 10^th abdominal tergite usually bilobate, either with evenly rounded lobes, lobes reduced to short bulges or strongly elongated. Male cerci simple, expanded at their tips or differentiated in differently-shaped branches. Subgenital plate elongated (but not markedly surpassing abdominal apex) with mostly a pair of short stout to more slender lobes or unlobed with two rounded apices at the posterior margin.

All checked specimens also have an area of dark cells surrounded by the green more elevated veins in the cubital area of the tegmina.

Cameroon (1♂, 1♀) (MCNM); Cameroon, Campo Ma’an National Park (lowland rainforest) (950 m alt.) 10–22. III. 2018 (UV Cold Cathode Light Trap), Fotsing, Ishmael, Miles, Safian (2♂ in ANHRT; 1♂ in BMPC); Gabon, Mikongo (Rougier), Mts de Cristal (secondary forest) (430 m alt.) 0°29'47"N, 11°10'42"E, 28. VII-12. VIII.2019 (LepiLED Light Trap), Albert, Aristophanous, Bie Mba, Dérozier, Moretto (1♂) (ANHRT); Gabon, Mts de Cristal National Park, Kinguelé 3. XII. 2015 (UV) (BMPC); Gabon, M’Bigon 26. I. 1986, A Pauly (1♂) (RBINS).

The 10^th abdominal tergite (Fig. 25) is similar to that of P. lamottei (Fig. 78) – with two lateral processes. However, the male cerci are completely different in P. africana, broader at the base tapering to acute tips of the two branches (Figs 22, 25, 28) while the male cerci in P. lamottei are simple, expanded into three tips apically (Fig. 78).

Tegmina about 5.8–5.9 longer than broad. Stridulatory file 0.3 mm long; teeth more widely spaced at inner side, becoming more densely set distally (Fig. 24). Fore femora unarmed. Mid femora with 4–5 outer ventral small spines, inner ventral side unarmed. Hind femora only distally with a ventral double row of 2–3 small spines. Fore tibiae with a ventral double row of 4–5 spines; mid tibiae with a ventral double row of 5 spines, hind tibiae with 4 rows of numerous spines and apically 3 spurs on each side. Last abdominal tergite enlarged and apically bilobate and flattened (Figs 22, 25, 26); cerci basally stout, apically divided into two tips, the inner shorter and incurved, the outer longer, flattened, outcurved and with 5–6 inner dark teeth like a knife (Figs 22, 25, 28). The subgenital plate is short with two stout lobes with rounded tips (Figs 26, 27).

Small species, uniformly green-yellowish, a little brownish around the stridulatory area (Fig. 23) and small black dots on the posterior margins of the tegmina.

(mm). Males. Body length: 18.5–19.9. Pronotum length: 3.7–3.8. Pronotum height: 2.8–2.9. Length of hind femora: 19.6–19.8. Length of tegmina: 26.5–26.8. Width of tegmina: 4.5–4.6.

Figures 22–28. 

Morphological details of male Poreuomena africana. Drawing Fig. 53, taken from Brunner von Wattenwyl (1878) (22), head and stridulatory area (23), stridulatory file on the underside of the left tegmen (24), apex in rear view (25) and lateral view (26), subgenital plate (27) and cerci (28).

Democratic Republic of the Congo. Léopoldville (today Brazzaville) 1937, A. Tinant (holotype ♂) (MRAC).

Very closely related to P. wilverthi, a species widespread in the Congo basin and the Albertine Rift. P. biaculeata sp. nov. has the 10^th abdominal tergite deeply split into two lobes (Figs 33, 34), while in P. wilverthi the 10^th abdominal tergite is not divided as deeply, just at the apex however, with a median groove. The cerci in P. wilverthi are thick but smoothly tapering to the apex with an acute tip (Figs 105, 106), while in P. biaculeata sp. nov., the cerci are thick at the base and then suddenly narrowing midway forming a finger-like but pointed and sclerotized apical section (Figs 32–34). P. biaculeata sp. nov. is also closely related to P. crassipes with a similar tegminal flap of the 10^th abdominal tergite but differently shaped cerci.

Male. Typical Poreuomena species with wings protruding over the body by only a few mm (Fig. 29). Where tegmina meet, when folded, interior part of cells of dark colour while surrounding and elevated veins green (tawny in preserved insect). Rs branching off in the first half of the basal part of the tegmen. Tegmina with two flaps at their base, the flap of the left wing smaller and more pointed than the broader flap with a rounded tip on the right tegmen. The stridulatory rib marked dark brown on the flap of the left tegmen, uniformly brown on the right tegmen. Beneath flaps, tegmina with narrow longish, oval brown markings. Stridulatory file on the underside of left flap about 1.1 mm long; teeth at the apical part of the left flap very densely set and gradually getting larger to the middle of the file where the teeth are largest and widely set. At the end of the file at the interior part, strongly curved with small and a few widely set teeth; with about 20 widely and in the middle large teeth, apically more than 30 very densely set teeth (Fig. 31). Stridulatory file on the right tegminal flap not as strongly developed but of similar shape and the same arrangement of the teeth. The 10^th abdominal tergite of typical bilobate form, deeply divided medially thus forming two processes with upcurved posterior parts (Figs 33, 34). Cerci thick at the base, then strongly narrowing and forming a sclerotised pointed apical tip (Figs 33, 34). Subgenital plate with two slender but short lobes (Fig. 35). Titillators present (two slender long structures), protruding between the subgenital plate and the cerci (Fig. 32).

Female. Unknown.

(mm). Male (n = 1). Body length: 22; pronotum length: 3.7; length hind femora: 21.2; length of tegmina: 28.3; width of tegmina: 4.3.

Congo Basin.

Named after the shape of cerci that are similar to two stings, from Latin biaculeatus (= with two stings).

Figures 29–35. 

Morphological details of male Poreuomena biaculeata sp. nov. Habitus (29), left tegminal flap with stridulatory file on the underside (30), stridulatory file on the underside of the left tegminal flap (31), abdominal apex in lateral (32) and rear view (33), cerci (34), subgenital plate (35).

Central African Republic, Dzanga-Ndoki National Park, Ndoki, Lake 1, UV trap 1, 31.I.-2.II.2012 (♂); 11–12.II.2012 (♂); 20–23.II.2012 (♂); Central African Republic, Dzanga-Ndoki NP, Lake 1, camp 1, 15–16.II.2012 (♂); Central African Republic, Dzanga-Ndoki NP, Lake 1, UV trap 2, 15–16.II.2012 (♂); Central African Republic, Dzanga-Ndoki NP, Lake 1, 11–12.II.2012 (light) (3♂); Lake 3, 25–26.II.2012 (light) (1♂) (BMPC); Central African Republic, Dzanga-Ndoki NP, Lake 1, 29–30.XI.2010 (1♂, 1♀); 30.XI-1.XII. 2010 (light) (1♂) (PAPC).

Morphologically closely related to P. biaculeata sp. nov. and P. wilverthi. All three species share a similar 10^th abdominal tergite that is flap-like, deeply divided into two lobes in P. biaculeata sp. nov. (Figs 33, 34), with an indentation only at its posterior margin and a central furrow in P. wilverthi (Fig. 107) and with only a shallow groove medially in P. crassipes (Fig. 40). The cerci of the three species are also similar, stout at their bases, narrowed halfway into a sclerotised tip in P. biaculeata sp. nov. (Figs 33, 34), evenly tapering into a tiny sclerotised tip in P. wilverthi (Figs 104, 106) and stout in P. crassipes with two sclerotised dents at their apices (Figs 39, 40).

Karsch (1890, p. 364, note 1) described very briefly only the female of C. crassipes from Cameroon. Massa (2013) described the male. The 10^th tergite is apically rounded with a clear bilobate incision (Fig. 40); the cerci are robust, up- and incurved, their apex is sharply narrowed and pointed (Figs 39, 40). The subgenital plate is not long, but clearly bilobate (Fig. 40). The stridulatory area of the left tegmen is black, short and straight (Fig. 37) and the stridulatory file has ca. 40 teeth, apically upcurved (Fig. 38).

(mm). Males. Body length: 17.3–19.6; pronotum length: 3.8–4.1; pronotum height: 3.3–3.6; length of hind femora: 19.3–20.2; length of tegmina: 27.3–30.6.

P. crassipes is known from Cameroon (Karsch 1890; Ragge 1968), the Central African Republic (Massa 2013; Massa et al. 2020), the Democratic Republic of the Congo and the Ivory Coast (Ragge 1967; 1968).

Figures 36–40. 

Morphological details of male Poreuomena crassipes. Habitus (36), stridulatory area (37), stridulatory file on the underside of the left tegminal flap (38), lateral (39) and rear view (40) on apex.

Cameroon, Mukonje Farm (♂ holotype, 4♀) (RBINS); Cameroon, Mukonje Farm (2♀ syntypes) (MSNG).

The 10^th abdominal tergite is hood-shaped with a small median indentation (Fig. 42). The cerci are stout within a sharp-angled incurved sclerotised tip (Figs 43, 44); the subgenital plate is bilobate (Fig. 44). No other Poreuomena species has a hood-shaped 10^th abdominal tergite and such peculiar cerci with tips acute-angled.

Known only from the type locality, Cameroon.

Figures 41–44. 

Morphological details of male Poreuomena duponti. Habitus (41), lateral view on apex (42), lateral view of cerci (43, 44).

Democratic Republic of the Congo, Eala, IV 1935. J. Ghesquiére (Holotype ♂) (MRAC); same data as holotype, but IV and XI 1935 (Paratypes 1♂, 2♀) (MRAC).

Rather stout species with a 10^th abdominal tergite differentiated into two bulges (Figs 48, 49). The cerci are stout and upcurved with stout bifurcate tips (Figs 48, 49). No other Poreuomena species has such a combination of bifurcate tips of the cerci and a 10^th abdominal tergite differentiated into two bulges.

Male. Stout species with wings projecting over the body by about half of their length. Where tegmina meet, when folded, interior part of cells of dark colour while surrounding and elevated veins green. Rs branching off in the first half of the basal part of the tegmen. Tegmina with two flaps at their base, the flap of the left wing smaller and more pointed than the broader flap with a rounded tip on the right tegmen. The stridulatory rib marked dark brown on the flap of the left tegmen, uniformly brown on the right tegmen. Beneath flaps, tegmina with narrow longish brown markings. Stridulatory file on the underside of the left flap about 1.3 mm long; teeth at apical part of the left flap very densely set and gradually getting larger, about from half of the file teeth large and more widely to very widely spaced; inner part then strongly curved and teeth becoming smaller and then obsolete; with about 45–50 teeth (Fig. 50). Stridulatory file on the right tegminal flap not as strongly developed, but of similar shape and the same arrangement of the teeth. The 10^th abdominal tergite bilobate, differentiated into two bulges (Fig. 48). Cerci stout along whole length, at their ends upcurved and divided into two tips (Figs 48, 49). Subgenital plate elongated, deeply divided into two lobes; without styli (Fig. 49). Between subgenital plate and cerci, two longish internal structures present (titillators) (Fig. 51).

Female. As male comparatively stout, of uniform green colour without brown markings (Fig. 45) present in males on and beneath the stridulatory area. As in the male, where tegmina meet when folded, interior part of cells of dark colour while surrounding veins green. Posterior margin of 10^th abdominal tergite differentiated into two lobes or bulges, similar to those of the male, but much smaller and shorter (Fig. 46). Ovipositor short and upcurved. Subgenital plate triangular with an indentation at the posterior tip (Fig. 47).

(mm). Males (n = 2). Body length: 22.7–23.1; pronotum length: 4.4–4.5; length hind femora: 22–22.5; length of tegmina: 30–31.5; width of tegmina: 4.4–5.2.

Females (n = 2). Body length: 19.5–22; pronotum length: 4.2–4.4; length of hind femora: 21–22.1; length of tegmina: 32–32.7; width of tegmina: 5.4–5.5; length of ovipositor: 6.4–6.5.

DRC, Équateur Province.

Named after the area Eala where specimens of this species were collected.

Figures 45–51. 

Morphological details of Poreuomena eala sp. nov. Habitus, female (45), subgenital plate (46) and lateral view on ovipositor (47), semi-lateral (48) and lateral (49) view on the male abdominal apex, stridulatory file on the underside of the male left tegminal flap (50), titillators (51).

Central African Republic, Dzanga-Ndoki NP, Lake 1, 14–15.II.2012, 19–20.II.2012 (light) (2♂) (BMPC).

Figures 52–56. 

Morphological details of male P. gladiator (= P. forcipata) (lectotypus). Habitus (52), stridulatory file on the underside of left tegminal flap (53), stridulatory area (54), dorsal view (55) and ventral view (56) on apex. Arrow in Fig. 55 shows the asymmetrical spine.

Cameroon, holotype ♂ of P. gladiator (MNCN) (Fig. 52).

Griffini (1908) supposed that, because Bolívar (1906) overlooked the paper of Sjöstedt (1902), P. gladiator Bolívar, 1906 from Cameroon could be synonymous with P. forcipata Sjöstedt, 1902, also from Cameroon. The male cerci of the two taxa are identical. Both lack the black marking on the stridulatory area of the male left tegmen (Fig. 54); thus P. gladiator has been synonymised with P. forcipata by Massa (2013). Morphologically most closely related to P. laeglae (both species share an asymmetrical supra-anal plate with a spine on the left margin, Fig. 55), P. tshuapa sp. nov. and P. magnicerca (also see diagnosis at P. laeglae).

Rather stout species with comparatively broad tegmina (Fig. 54). The 10^th abdominal tergite is broad with two lateral processes, while the cerci are highly modified into two branches (Figs 55, 56). The inner branch is blade-like with sclerotised margins, while the outer or apical one is finger-like (also see at P. tshuapa sp. nov.). This species has an asymmetrical supra-anal plate with a stout spine on the left side, lacking on the right (Massa et al. 2020; Fig. 55 arrow). The male subgenital plate is triangular and has a small apical concavity (Fig. 56). The stridulatory file has ca. 35 teeth, the last 8–10 placed more or less perpendicularly to the main file (Fig. 53).

Cameroon and the Central African Republic.

Zaire (Democratic Republic of the Congo), 180 km W from Bukavu, rainforest, 14.V.1988, leg. A. Vojnits et al., Arthropoda collected at 160 W MV lamp, No. 320 (Teleki expedition) (Holotype ♂) (HNHM); Democratic Republic of the Congo, Kivu, Terr. Mwenga, Kitutu, 650 m alt. (lumiere), IV.1958, N. Leleup (Paratype ♂) (MRAC).

The elongated and slender shape of the male cerci – thickened in the middle with an inner dent – and the 10^th abdominal tergite forming two long downcurved processes are unique.

Male. Typical Poreuomena species with wings protruding over the body by only a few mm. Where tegmina meet when folded, interior part of cells of dark colour while surrounding and elevated veins green (or tawny in preserved insect). Rs branching off in the first half of the basal part of the tegmen. Tegmina with two flaps at their bases, the flap of the left wing smaller and more pointed than the broader flap with a rounded tip on the right tegmen. Left flap completely marked brown, right one partly brown, especially along the bulge of the stridulatory file on the underside (Fig. 57). Beneath flaps, tegmina with narrow longish, dark brown markings. Stridulatory file on the underside of left flap about 1.2 mm long; upcurved at the inner end with few smaller and widely-spaced teeth (about 5), in the middle part with widely set large teeth (about 12) and, at the apical end, with densely-set teeth decreasing in size (about 10–12); distal end strongly curved downwards (Fig. 58). Stridulatory file on the right tegminal flap not as strongly developed, but of similar shape and the same arrangement of the teeth. The 10^th abdominal tergite forming at the anterior part two convex bulges, at its posterior end differentiated into two long and slender and downcurved processes (Figs 60, 61). Cerci strongly elongated, in the middle thickened with an inner sclerotised dent. Subgenital plate bilobate (Fig. 59).

Female. Unknown.

(mm). Males (n = 2). Body length: 18.2–18.6; pronotum length: 3.9–4.05; length hind femora: 19.3–19.6; length of tegmina: 28.6–29.15; tegmina width: 4.98–5.0.

Democratic Republic of the Congo.

Named after the long and slender male cerci.

Figures 57–61. 

Morphological details of male Poreuomena gracilicercata sp. nov. Head, pronotum and stridulatory area (57), stridulatory file on the underside of the left tegminal flap (58), subgenital plate (59), lateral (60) and rear view (61) on apex.

Equatorial Guinea, Bioko (Fernando Poo), Santa Isabel (♂ holotype) (MCNM); Cameroon, Gulf of Guinea Is, Bioko (Fernando Poo), Santa Isabel (Malabo) (1♂) (NHMW).

This species is easy to recognise by the short apical lobes on the 10^th tergite of the male and cerci clearly upcurved and with a lateral spine. The most closely-related species is P. africana, which, however, has much longer lobes of the 10^th abdominal tergite and more robust cerci.

Typical Poreuomena species with narrow tegmina surpassed by the alae by a few mm (Fig. 62). Stridulatory area marked brown (Fig. 64). Two spines are present on the ventral margin of the hind femora. The apical lobes of the 10^th tergite are short and square, separated widely (Fig. 63); the cerci are in- and downcurved, dorso-ventrally flattened in the apical portion where a lateral spine is present.

P. huxleyi is brownish coloured, with green tegmina and hind tibiae; a black marking is typical at the base of the tegmina and some small black spots on the posterior margin of the tegmina.

Equatorial Guinea and Cameroon.

Figures 62–64. 

Morphological details of male Poreuomena huxleyi. Habitus (62), lateral view on apex (63), stridulatory area (64).

Côte d’Ivoire, Taï National Park, Research Station 22.III-4.IV.2017 (light) (♂ holotype) (BMPC).

P. ivoriana sp. nov. is a comparatively small species of Poreuomena, characterised by its green colour, the blackish triangular areas on the left and right tegmina (Fig. 65) and incurved cerci with a flattened inner process (Figs 67, 68). Probably morphologically related to P. lamottei distributed further west in Africa. The male cerci of both species are differentiated into flattened structures in both species, however, more pronounced in P. ivoriana sp. nov. The 10^th abdominal tergite is very different in both species. While in males of P. lamottei, the posterior margin of the 10^th abdominal tergite forms two comparatively long and, at their tips, downcurved processes, in P. ivoriana sp. nov. only two short lobes are developed.

Male. Green coloured with a faint blackish stripe on the stridulatory area; the triangular area close to the stridulatory file above the left tegmen and the corresponding area on the right tegmen are black. Antennae thin, fastigium of the vertex separated from the fastigium of the frons, face smooth, eyes round, prominent. Pronotum with a flat and smooth disc, the anterior margin straight, the posterior margin broadly rounded. Tegmina narrow, ca. 5.8 times broader than long, stridulatory area of the left tegmen short. The flap of the left tegmen comparatively broad (damaged in the holotype) (Fig. 65). The corresponding flap on the right tegmen also broad. Stridulatory file 0.3 mm long, with ca. 45 little arched teeth which are more evenly spaced at their base than at the apex (Fig. 66). Fore coxa armed with a small spine, fore femora with 4 small spines on ventral inner margins, mid femora with 4–5 small spines on ventral outer margins, hind femora with 2–3 rows of small ventral spines distally. Fore tibiae with tympanum conchate on inner and open on the outer side, with 2–3 small spines on inner margins, mid tibiae with 9–10 small spines on outer and inner margins, hind tibiae with numerous spines and 3 apical spurs on each side. Last abdominal tergite flattened and enlarged with two apical small pointed processes, cerci stout, short and incurved, before their tips, they have an inner flattened process (Figs 67–69). Subgenital plate long with a narrow concavity and two parallel pointed processes; styli absent (Fig. 69).

(mm). Male. Body length: 19.0; pronotum length: 4.1; pronotum height: 2.3; length hind femora: 18.2; length of tegmina: 23.3; width of tegmina: 4.0.

P. ivoriana sp. nov. is named after the Côte d’Ivoire.

Presently known only from the Taï National Park (Côte d’Ivoire).

Figures 65–69. 

Morphological details of male Poreuomena ivoriana sp. nov. Stridulatory area (65), stridulatory file on the underside of the left tegminal flap (66), view on male cerci in dorsal (67) and lateral view (68), subgenital plate (69).

Côte d’Ivoire, Tuba, Biémasso (441 m) 9.VII.2014 (UV trap) (♂ holotype) (MSNG); same locality, 7–11.VII.2014 (♂ paratype, ♀ allotype); same locality, 9.VII.2014 (♂ paratype); Côte d’Ivoire, Taï National Park Research Station 18.III.2017 (1♂); Côte d’Ivoire, Mt. Tonkoui 31.X.2018 (1♀) (BMCP); Liberia, Lofa County, Wologizi Mts. (611 m alt.) 20.XI-1.XII.2017 (MV Light trap) (2♂); Liberia, Lofa County, Wologizi Mts. (611 m alt.) 24–29.XI.2017 (Light Catode Trap) (1♂); Liberia, Lofa County, Foya Proposed Protected Area (530 m alt.) 10–19.XI.2017 (MV light Trap) (6♂); Liberia, Sinoe County, 6.5 km NW Jacksonville Forest near Solve Problem Vill. (103 m alt.) 23–27.I.2018 (MV Light trap) (2♂) (ANHRT).

P. laeglae was described in the genus Cestromoecha, but it actually belongs to the genus Poreuomena because it has two well-developed tegminal flaps and no mirror. The Rs vein branches off near the base and not past the middle as typical for Cestromoecha. It is morphologically most closely related to P. forcipata (both species share an asymmetrical supra-anal plate with a spine on the left side) and also to P. magnicerca and P. tshuapa sp. nov. The cerci of the males are differentiated into two branches in the first two species, with a finger-like apical or outer branch and a blade-like expanded inner branch, however, differently shaped between P. laeglae and P. forcipata. In P. magnicerca and P. tshuapa sp. nov., the third blade-like branch or expansion is present giving the expression of the cerci having three branches. The flaps on the left tegmina bearing the stridulatory files on the underside are differently shaped between P. tshuapa sp. nov. (oval and pointed) and P. magnicerca (laterally slightly expanded and not pointed) as is the shape of the stridulatory file itself supporting species status for P. tshuapa sp. nov. The 10^th abdominal tergites, however, are very similar amongst these four species since they are rather undifferentiated with a more or less straight posterior margin and thus very likely derived from the bilobed condition as the generic character of the genus Poreuomena.

The stridulatory file of P. laeglae is similar to that of P. magnicerca with a distal part with less and more widely-spaced teeth than in the proximal part (Massa 2015).

Typical Poreuomena species with elongated habitus. Fore and mid femora with 4–5 very small spines, fore tibiae with 3 ventral spines + 1 spur on each side, mid tibiae with 6–7 ventral spines + 1 spur on each side, hind tibiae with 3 spurs on each side. Ventral margins of hind femora with 2 small basal spines. Tegmina narrow, stridulatory area of left tegmen black and straight; stridulatory file downcurved with ca. 50 teeth, distal part with asymmetrical and widely-spaced teeth (Fig. 71). The 10^th tergite slightly bilobate with an asymmetrical supra-anal plate having a spine on the left side at the margin (Fig. 72, arrow) (similar to P. forcipata, Fig. 55, arrow). Cerci stout, long and incurved, with the basal part rounded and the apical part flattened and pointed (Fig. 72); in the middle, with a well-developed flattened large inner spine, blackish at the tips (Fig. 73). Subgenital plate concave, triangular and long, with a deep concavity, processes almost parallel (Fig. 74).

Probably predominantly green when alive, brown to tawny when preserved. Stridulatory area of left tegmen and area below black. Small black spots are present on the posterior margins of the tegmina. Two longitudinal parallel dark lines are present on the outer surface of the hind femora.

(mm). Males. Body length: 18.5–19.4; pronotum length: 4.0–4.2; pronotum height: 3.4–3.6; hind femur: 18.2–20.7; tegmina: 26.4–27.5.

Female. Body length: 21.7; pronotum length: 4.0; pronotum height: 3.4; hind femur: 20.8; tegmina: 29.4; ovipositor: 6.1.

Presently only known from the Ivory Coast and Liberia in West Africa.

Figures 70–74. 

Morphological details of male Poreuomena laeglae stat. nov. Head, pronotum and part of abdomen in lateral view (70), stridulatory file on the underside of the left tegminal flap (71), lateral view on cerci and 10^th abdominal tergite (72), cerci lateral view (73), subgenital plate and cerci (74). Arrow in Fig. 72 shows the small asymmetrical spine.

Côte d’Ivoire, Azagny National Park (light trap) (3♂); Côte d’Ivoire, Taï National Park, Res. Station 5–10.VII.2015 (light trap) (1♂) (NHM).

P. lamottei has a similar 10^th abdominal tergite as P. eala sp. nov., but the lobes are much narrower and have a large gap between them in P. lamottei. In addition, the male cerci are similar between the two species, stout and upcurved at their tips, however, with bifid tips in P. eala sp. nov.

Typical Poreuomena species with stridulatory area marked dark brown (Fig. 75). The stridulatory file is arched and consists of about 60 teeth, of which roughly 30 large teeth are situated in the distal part and 30 smaller and evenly-spaced teeth in the proximal part (Fig. 76). The last tergite is differentiated into two stout and downcurved processes (Figs 77, 78); the subgenital plate is elongated with two outcurved lobes (Fig. 79); the cerci are stout and incurved and possess an apical flat tip with three short processes (Fig. 78).

Guinea, Ghana (Chopard 1954; Naskrecki 2009) and Ivory Coast (Massa 2017).

Figures 75–79. 

Morphological details of male Poreuomena lamottei. Stridulatory area (75), stridulatory file on the underside of the left tegminal flap (76), lateral (77) and dorsal view (78) on apex of abdomen, subgenital plate (79).

Central African Republic, Dzanga-Ndoki National Park, Lake 1, UV trap, 6–8.II.2012 (Holotype ♂) (MSNG); same data (paratype ♂); same data 11–12.II.2012 (paratype ♂); same data 20–23.II.2012 (paratype ♂); Central African Republic, Dzanga-Ndoki NP, Mboki 24.I.2012 (2 paratypes ♂); Central African Republic, Dzanga-Ndoki NP, Ndoki, Lake 1, camp 1, 15–16.II.2012 (2 paratypes ♂) (BMCP); Central African Republic, Dzanga-Sangha Special Reserve, Camp 1, 27–28.I.2005 (light) (1♂); Central African Republic, Dzanga-Ndoki NP, Lake 1, 22–23.XI.2010, 30.XI-1.XII.2010 (light) (2♂) (PAPC); Central African Republic, Dzanga-Ndoki NP, Lake 1, 1–2.II.2012, 4–5.II.2012, 9–10.II.2012, 12–13.II.2012, 14–15.II.2012 17–18.II.2012, 19–20.II.2012, 23–24.II.2012 (light) (6♂, 4♀); Central African Republic, Dzanga-Ndoki NP, Lake 7, 29.II-1.III.2012 (light) (1♂) (BMPC & PAPC).

Compare diagnoses at P. laeglae, P. tshuapa sp. nov., and P. forcipata.

P. magnicerca was described in the genus Cestromoecha, but actually belongs to the genus Poreuomena since sharing all generic characters with this genus and lacking a mirror on the right tegmen, typical for Cestromoecha. The stridulatory area of the left tegmen is black (Figs 80, 81); the stridulatory file is long and straight and has about 50 teeth (Fig. 82) and is clearly longer and has smaller teeth than C. longicerca. The cerci are stout, long and incurved, with the basal part rounded and the apical part pointed; they appear trifid because, subapically, they have a well-developed upper laterally flattened bulge and an inner long spine (Figs 83, 84). The subgenital plate is concave, triangular and elongated, with a deep concavity and with processes positioned very close to each other (Fig. 85).

Probably predominantly green when alive, brown to tawny when preserved. The stridulatory area of the left tegmen and the area below black. Small black spots are present on the posterior margins of the tegmina.

(mm). Males. Body length: 19.5–21.0; pronotum length: 3.9–4.0; pronotum height: 3.4–3.6; length of hind femora: 19.4–21.7; length of tegmina: 30.3–33.0.

Females. Body length: 17.7–21.0; pronotum length: 4.1–4.9; pronotum height: 3.1–4.0; length of hind femora: 18.8–21.7; length of tegmina: 27.7–29.2; width of tegmina: 4.6–5.0; length of ovipositor: 5.1–5.9.

Known only from the Central African Republic.

Figures 80–85. 

Morphological details of male Poreuomena magnicerca stat. nov. Stridulatory file on the underside of the left tegminal flap (80), stridulatory area with closed (81) and left opened wing (82), lateral (83) and dorsal view on apex (84), subgenital plate (85).

Gabon, Lope National Park, Ogooue-Ivindo 4.IV.2014, Ecotrop Team (♂ holotype) (BMPC).

P. matthaei sp. nov. is a comparatively large Poreuomena species, characterised by its yellowish colour, whitish triangular areas on the left and the right tegmina and incurved cerci with a flattened blackish tip. The 10^th abdominal tergite is similar to that of P. gracilicercata sp. nov. Both species, however, have differently-shaped male cerci. While all other Poreuomena species have flaps at the bases of the tegmina, in P. matthaei sp. nov. only the area at the base of the right tegmen is developed as a flap, while on the right side, a bulge is present (Fig. 86).

Male. Yellowish-cream coloured with a faint blackish stripe on the stridulatory area (Fig. 86); the triangular area close to the stridulatory file above the left tegmen and the corresponding area on the right tegmen are whitish. Antennae thin, fastigium of the vertex separated from the fastigium of the frons, face smooth, eyes round, prominent. Pronotum with a flat and smooth disc, the anterior margin straight, the posterior margin broadly rounded (Fig. 86). Tegmina narrow, ca. 10.7× broader than long; stridulatory area of the left tegmen comparatively long for the genus. Stridulatory file 0.5 mm long, with ca. 70 slightly arched teeth which are more evenly spaced at their base than at the apex (Fig. 87). Fore coxa armed, fore femora with 4 small spines on the ventral inner margins, mid femora with 5–6 small spines on the ventral outer margins, hind femora with 3–4 rows of small ventral spines distally. Fore tibiae with the tympanum conchate on the inner and open on the outer side, with 3–4 small spines on the inner margins, mid tibiae with 3–4 small spines on the outer margins, hind tibiae with numerous spines and 3 apical spurs on each side. Last abdominal tergite flattened and enlarged (Figs 88, 89), cerci basally stout, long and incurved, their tips blackish and flattened. Subgenital plate elongated with two roundish lobes (Fig. 90).

Female. Unknown.

(mm). Males. Body length: 23.6; pronotum length: 4.8; pronotum height: 2.7; length hind femora: 22.8; length of tegmina: 32.0; width of tegmina: 3.0.

P. matthaei sp. nov. is dedicated to the late Matteo Griggio, who at the age of 43 left us on 14 May 2020 due to an aneurysm. Matteo was a lively behavioural ecologist who was also very committed to nature conservation, curious about every particular aspect of nature, including Orthoptera as a food source for the Rock Sparrow in Sardinia.

Presently known only from the Lope National Park (Gabon).

Figures 86–90. 

Morphological details of male Poreuomena matthaei sp. nov. Head, pronotum and stridulatory area (86), stridulatory file on the underside of the left tegminal flap lateral (87), lateral (88) and rear view on apex (89) and subgenital plate (90).

Central African Republic, Dzanga-Ndoki National Park, Lake 1, UV trap, 10–12.II.2012 (holotype ♂) (MSNG); same data 20–23.II.2012 (allotype ♀); same data 8–10.II.2012 (paratype ♂); same data 20–23.II.2012 (5 paratypes ♂); same data 31.I-2.II.2012 (1 paratype ♂) (BMPC); Central African Republic, Dzanga-Ndoki National Park, border of Lake 1, 13–14.II.2012 (2 paratypes ♂) (BMPC); Central African Republic, Dzanga-Ndoki National Park, Lake 1, camp 1, 14–15.II.2012 (paratype ♂) (BMCP); Central African Republic, Dzanga-Sangha SR, Camp 3, 4–6.II.2005 (2♂); 10–11.X.2008; Camp 1, 14–15.X.2008 (light) (2♂) (PAPC); Central African Republic, Dzanga-Ndoki NP, Lake 1, 30.XI-1.XII.2010 (light) (1♂); Central African Republic, Dzanga-Ndoki NP, Lake 1, 25–26.I.2012 (light), 9–10.II.2012, 10–11.II.2012, 14–15.II.2012 (light) (6♂) (BMPC & PAPC). Cameroon, Campo Ma’an National Park (lowland rainforest) (950 m alt.) 10–22.III.2018 (MV Light Trap), Fotsing, Ishmael, Miles, Safian (1♂); Cameroon, Campo Ma’an National Park (lowland rainforest) (950 m alt.) 10–22.III.2018 (UV Cold Cathode Light Trap), Fotsing, Ishmael, Miles, Safian (2♂); Gabon, Mikongo (Rougier), Mts de Cristal (secondary forest) (430 m alt.) 28.VII-12.VIII.2019 (MV Light Trap), Albert, Aristophanous, Bie Mba, Dérozier, Moretto (3♂) (ANHRT).

Small and fragile species, green (alive) or brown (preserved) coloured, with a brown-reddish upper area of the abdominal tergites. The 10^th abdominal tergite of P. sanghensis is similar to P. wilverthi, however, not downcurved, but produced posteriorly with a deep median fold. The male cerci are also similar between these two species, however, much more fragile-built in P. sanghensis.

Typical Poreuomena species with an elongate habitus (Fig. 91). Stridulatory area of the left tegmen short and straight (Fig. 92). The stridulatory file has ca. 40 teeth, of which 7–8 are proximally placed nearly perpendicularly to the others (Fig. 93). The ventral margins of the hind femora have 2 spines. The 10^th tergite ends with two short reddish rounded flat lobes with an inner spine (Figs 94, 95); the cerci have a wide round base, with an inner spine, then becoming narrower; upcurved and pointed apically (Figs 94–96). The male subgenital plate is stout, the processes are slender and incurved, forming a circular space between them (Fig. 96).

Predominantly green when alive, brown to tawny when preserved; dorsal area of abdominal tergites brown-reddish. A black marking is present at the base of the tegmina of the male, absent in the female.

(mm). Males. Body length: 15.2–17.5; pronotum length: 3.0–3.2; pronotum height: 2.5–2.7; length hind femora: 16.0–18.8; length of tegmina: 23.6–24.8.

Female. Body length: 19.4; pronotum length: 3.3; pronotum height: 2.8; length of hind femora: 19.2; length of tegmina: 30.0; length of ovipositor: 3.9.

Central African Republic (Dzanga-Ndoki National Park and Dzanga-Sangha Special Reserve), Cameroon (Massa 2013; 2015), and Gabon (Massa, in press).

Figures 91–96. 

Morphological details of male Poreuomena sanghensis. Habitus (91), stridulatory area (92), stridulatory file on the underside of the left tegminal flap (93), rear (94) and lateral (95) view on apex, subgenital plate (96).

Democratic Republic of the Congo, Tshuapa, Bokungu 1949, M. Dupuis (Holotype ♂); same data as holotype (Paratype ♂); Democratic Republic of the Congo, Haut-Lopori V-VI 1927, J. Ghesquiére (Paratype ♂) (MRAC).

Similar in the outer male genitalic apparatus to P. magnicerca from further west in the Congo Basin. Differentiated from P. forcipata and P. laeglae by a different 10^th abdominal tergite which is clearly divided into two lobes in P. forcipata, while P. tshuapa sp. nov. only has small humps and the posterior margin of the 10^th abdominal tergite of P. laeglae is more-or-less straight. P. forcipata has male cerci differentiated into two branches, an outer rather blunt, finger-like part and an inner blade-like expanded branch with an acute tip, similar to the inner branch of P. tshuapa sp. nov. and P. magnicerca. However, P. tshuapa sp. nov. has an additional branch just below the finger-like part of the cerci, absent in P. forcipata, but also present in P. magnicerca (also see diagnosis at P. laeglae). In P. magnicerca, the blade-like subapical section or the “third” branch is more roundish and larger than in P. tshuapa sp. nov. and the subgenital plate differs between these two species. In P. tshuapa sp. nov., the subgenital plate is bilobate with the processes clearly separated, while in P. magnicerca, the lobes of the subgenital plate are shorter and situated more closely to each other. Further, in P. forcipata and P. laeglae, asymmetrical spines are present on the left side of the supra-anal plates.

Male. Probably predominantly green when alive, preserved specimens of tawny colour (Fig. 97). Where tegmina meet when folded, interior part of cells of dark colour while surrounding and elevated veins green/tawny. Typical Poreuomena species with Rs branching off from the radius near the base. The tegmina have two typical well-developed flaps at their base, the flap on the left side smaller and more pointed than the flap on the right tegmen. Beneath the flaps, tegmina with narrow longish brown markings are typical for several Poreuomena species. The stridulatory file on the left tegminal flap is about 1.5 mm long with small broadly-spaced inner teeth becoming gradually larger and are more densely set (Fig. 98). The last third consists of very densely packed teeth becoming smaller again; the apical part is strongly curved. All-in-all, the stridulatory file consists of about 70–80 teeth. Stridulatory file on the underside of the right tegmen not as well-developed, but similar in shape and size and arrangement of the teeth. The 10^th abdominal tergite has almost a straight posterior margin with only two bump-like structures laterally (Fig. 99). The cerci are stout, divided at their apical part into three branches: a subapical blade located just beneath the second elongated, finger-like branch and an inner blade-like or leaf-like expanded branch with sclerotised margins (Figs 99, 100). The subgenital plate is elongated and deeply divided into two lobes; without styli (Fig. 100). Between the subgenital plate and the cerci, two longish internal structures are present (titillators).

Female. Unknown.

(mm). Males (n = 3). Body length: 17.7–18.2; pronotum length: 3.8–4.1; length hind femora: 20.3–21.2; length of tegmina 29.6–30.4; width of tegmina: 4.6–5.0.

Democratic Republic of the Congo, Tshuapa Province.

Figures 97–100. 

Morphological details of male Poreuomena tshuapa sp. nov. Habitus (97), stridulatory file on the underside of the left tegminal flap (98), different views on apex with cerci (99, 100).

Democratic Republic of Congo, Umangi IX-XI.1896 (♂ holotype) (RBINS). Central African Republic, Lesse, Lt. Bonnevie (1 ♂); Democratic Republic of Congo, Binga, 8-III-1932, H. J. Bredo (1 ♂) (MRAC); Democratic Republic of the Congo, N Lac Kivu, Rwankwi, IV 1948, J. V. Leroy (MRAC); Democratic Republic of the Congo, Yamgambi, 15.6.1949, Rev Pére, J. K. A. van Boven (1 ♂) (MRAC); Democratic Republic of the Congo, Yambata, II/III -1914, Dr Giorgi (2♂) (MRAC); Democratic Republic of the Congo, 180 km W from Bukavu, rainforest, 14.V.1988, leg. A. Vojnits et al., Arthropoda collected at 160 W MV lamp, No. 320 and 326 (Teleki expedition) (1♂) (HNHM).

Male. Typical Poreuomena species with wings protruding over the body by only a few mm (Figs 101, 102). Where tegmina meet when folded, interior part of cells of dark colour while surrounding and elevated veins green (tawny in preserved insect). Rs branching off in the first half of the basal part of the tegmen. Tegmina with two flaps at their base, the flap of the left wing smaller and more pointed than the broader flap with a rounded tip on the right tegmen. The stridulatory rib and surrounding part of the flap of the left tegmen marked dark brown, few patches of brown on right tegmen. Area beneath flap with large brown marking. Stridulatory file on the underside of left flap about 1.2 mm long; the area at the inner side of the file strongly curved; with a few small widely-set teeth (Fig. 103). This part is followed to about the middle of the file by about 16–18 large and increasingly more densely-set large teeth changing then to about 40 or more very densely-set teeth decreasing in size apically. Stridulatory file on the right tegminal flap not as strongly developed, but of similar shape and the same arrangement of the teeth. The 10^th abdominal tergite a rounded flap with a median groove and an indentation at the posterior margin giving the structure a bilobate shape (Figs 106, 107). The cerci are thick and slightly incurved with a very narrow and pointed tip (Figs 104–107). The subgenital plate is bilobate with short lobes with rounded tips (Fig. 105). Between the subgenital plate and the cerci, thick blade-like titillators are present (Fig. 107).

Figures 101–107. 

Morphological details of male Poreuomena wilverthi. Habitus (101, syntype, 102), stridulatory file on the underside of the left tegmen (103), lateral view on apex (104), subgenital plate (105), apex ventral-lateral (106) and dorsal-lateral view (107).

Female. Unknown.

(mm). Males (n = 7). Body length: 17.2–19.5; pronotum length: 3.7–4.0; pronotum height: 2.6–3.0; length hind femora: 18.5–23.2; length of tegmina: 27.9–30.0. Width of tegmina: 3.8–5.1.

Widespread west of the Albertine rift into the area of the Central African Republic.

At present only the holotype was known. The new material studied coming from the Natural History Museum of Budapest and the Africamuseum Tervuren considerably enlarges the known area of distribution of this species (Fig. 111).