Pterotiltus impennis (Karsh, 1891).

Ramme 1929: 313. Johnston 1956: 258. Jago 1964: 190–204. Dirsh 1965: 579. Johnston 1968: 173. Dirsh 1970: 119. Hollis 1975: 226. Rowell 2005: 33–43.

Body of small to medium size. Integument rugose and pitted on head, thoracic and proximal abdominal tergites, but otherwise smooth and shiny.

Head . Antennae filiform, longer than head and pronotum together, especially in males. Fastigium of vertex roughly triangular or pentagonal in dorsal view, short, wider than long, sloping forwards, slightly concave, sometimes with a weak medial carinula; the apex runs smoothly into the frontal ridge. Frons oblique and sometimes slightly incurved in male, in female almost vertical or only slightly oblique; frontal ridge clearly defined in its upper half, with shallow medial sulcus, but weak or obliterated in lower half. Lateral facial carinae complete. Eyes small or large, almost round or oval, strongly convex; interocular space in males narrower, in females equal to or slightly wider than antennal scape.

Thorax . Dorsum of pronotum cylindrical, crossed by three deep transverse sulci, medial carina absent or very weak, lateral carinae absent; mesosternal interspace as long as wide or longer than wide. Metasternal interspace open or nearly closed. Prosternal tubercle simple, conical, vertical, with acute or slightly rounded apex. Tegmina and hind wings absent or extremely reduced, usually represented only by small ridges of integument on mesothorax and metathorax. In some species, minute tegmina are discernable, not extending beyond the hind margin of the mesothoracic segment. Hind femur slender (4–5 times as long as wide), its tip exceeding the end of the abdomen. Lower lobe of hind knee spined, as is typical for the subfamily. Hind tibia moderately expanded distally, with 9 internal and 7 external spines. External apical spine present. Internal tibial spurs much larger than external spurs. Arolium large. Second tarsal segment very short (ca. 15% of foot), third segment long (50–60%).

Abdomen. Tympanum oval or circular. Last abdominal tergite of male partially divided with a minute furcula, the paired projections in some species fusing to form a single medial process or a short medial tubercle. Male supra-anal plate widely triangular, very short. Female supra-anal plate somewhat longer and more lingulate than in male. Male and female cerci laterally compressed, triangular in lateral view, wide at base, narrowing to an acute or spine-like apex, straight or slightly incurved in dorsal view. Male subgenital plate very short, rounded. Ventral surface of female subgenital plate flat or smoothly rounded, its posterior margin straight or concave, never with posteriorly directed processes (vide Parapterotiltus gen. nov.). Dorsal valves of ovipositor laterally compressed, with rounded apices; ventral valves smooth, slender, straight, rod-like, sometimes dorsally flattened or slightly grooved. Egg guide prolonged horizontally rearwards between the ventral valves, up to half the length of the latter, straight or weakly curved, sharply pointed. Spermathecal vestibule large, sac-like; spermatheca with small apical diverticulum and a large curved subapical diverticulum.

Epiphallus with divided bridge, ancorae absent or extremely reduced, and one or two pairs of lophi; in most species, the outer lophi are long, slender, blade-like, and curved forwards. Ectophallic membrane well developed, including a ventrolateral sclerite encircling the ventral half of the ectophallus. Cingular valves fused together with the arch sclerite and elaborated into a valvular plate (Hollis 1971) covering the aedeagus dorsally and often laterally. In many species, this plate is foliose, being extensively ornamented with cuticular folds and lamellae, often of species-specific form. Endophallus with a slender flexure leading to short processes that do not themselves form aedeagal valves. Aedeagus composed of the valvular plate and of ventral aedeagal sclerites on which the endophallic processes terminate.

The known species of Pterotiltus are morphologically extremely homogenous, outwardly differing principally in size and coloration. Their phallic structures are more diverse, especially the epiphallus and the valvular plate. Where both sets of data are available, phallic diversity confirms the species boundaries originally drawn on the basis of coloration.

Holotype: ♂; CAMEROON •; High-Nyong Division, Ngoyla, Nki National Park; altitude 510 m; 10 May 2021; C. Oumarou Ngoute leg.; specimen no. 2021007; MfN. Paratype: CAMEROON • 1♀; same data as holotype; specimen no. 2021006; MfN. Other material examined: CAMEROON • 12 ♂, 1 ♀; same data as holotype; personal collection of C. Oumarou Ngoute.

Cameroon, High-Nyong Division, Ngoyla, Nki National Park.

Toponymic, referring to the locality of Ngoyla, Cameroon.

Color of body as in Fig. 2A, B: multi-colored, predominantly green with black and yellow markings, eyes noticeably violet in life. Average size of body: 20.3 mm (males) and 24.4 mm (females) (Table 1). Metazona of pronotum short, about one-fourth the length of prozona (Fig. 3C, D). Tegmina extremely reduced, narrow, and straight, not reaching the posterior margin of mesothoracic segment (Fig. 5). Furcula of the last abdominal tergite in male with acute corners either side of the midline (Fig. 3A), separation of tips 0.53 mm. Epiphallus as in Fig. 4G, H: large forwardly curved blade-like outer; inner lophi absent; anterior processes of epiphallus well developed, forward pointing; ancorae absent; oval sclerites present, with two small tubercles on their ventral surfaces.

Fig. 2. 

Pterotiltus ngoylaensis sp. nov. and Pterotiltus campoensis sp. nov. habitus. A. P. ngoylaensis male; B. P. ngoylaensis female; C. P. campoensis male; D. P. campoensis female.

Fig. 3. 

Pterotiltus ngoylaensis sp. nov. A. Dorsal view of male terminalia; B. Thoracic sterna; C. Pronotal disc showing sulci; D. Pronotal disc showing coloration and patterning in life. Scale bar: 1 mm.

Fig. 5. 

Pterotiltus ngoylaensis sp. nov., elytral rudiments. A. Female; B. Male, lateral view of elytra (shaded) at posterior edge of pronotum. PRNMZ, metazona of pronotum; T2 TG, mesothoracic tergite; T2 EPST, mesothoracic episternum, T2 EPMR, mesothoracic epimeron; T3 TG, metathoracic tergite; CXM, coxal membrane. Scale bar: 1 mm.

Fig. 4. 

Diagrams of phallus of Pterotiltus ngoylaensis sp. nov. A. Lateral view of entire phallic complex, shown somewhat extended relative to the resting state. Ectophallic membrane is coarsely stippled and obscures most of the sclerites. The ventrolateral sclerite (shaded) lies in this membrane and is clearly visible in the extended preparation. The cingular apodeme and the cingular ramus are indistinctly visible through the membrane (partially dashed line). Parts of the epiphallus and of the ventral aedeagal valve (shaded) are seen protruding through the membrane. The cingular valves are replaced by a valvular plate (sensu Hollis, 1971), which is foliose in this genus, as shown in B. and E. below; B, C. Endo- and ectophallic structures dissected free of epiphallus and ectophallic membrane (scale bar does not apply) in (B) dorsal and (C) lateral views. In C, the approximate course of the endophallic flexure and aedeagal valve are shown with dashed lines; D. Lateral view of the arch sclerite and its associated valvular plate dissected free from the cingulum. The whole structure is saddle-shaped, being concave ventrally and fitting over and around the ventral aedeagal valve (C); E. Dorsal view of the arch and its valvular plate showing its multiple lobes. The dashed vertical lines indicate denser areas seen in transmitted light, which suggest the presence of paired cingular valves but is illusory, as no such valves are present; F. Lateral view of endophallus dissected free of the arch and the cingulum. Heavily shaded areas are sclerotised. The lightly shaded area is the ventral aedeagal sclerite on which the endophallic process terminates and which forms the visible part of the ventral aedeagal valve; G, H. Epiphallus in (G) axial and (H) dorsal view. This species has only a single pair of external lophi, which are long, bladelike, and curved forward over the bridge. The “oval” sclerites are shaded in G and have two small tubercles on their ventral surface, indicated in H, a peculiarity of this species. Scale bar: 1 mm.

(Figs 2–5, Table 1).

Male. Body of medium size (average L = 20.3 mm). Fastigium of vertex pentagonal, about three times wider than long; frons slightly oblique; eyes large, oval, protuberant; interocular space equal to or slightly wider than antennal scape. Pronotum: medial carinae absent (Fig. 3C, D); the space between sulci 2 and 3 almost equal to the length of metazona; metazona short, about one-fourth of the length of prozona, and only 19% of the total pronotal length; posterior margin of metazona slightly notched in the midline, otherwise straight; anterior margin of pronotum slightly convex, minutely notched in midline; prosternal process conical, pointed; mesosternal space as wide as long; metasternal space open, about half the length of mesosternal space (Fig. 3B). Tegmina extremely reduced: in male, minute, narrow and straight, not reaching the posterior margin of mesothoracic segment, in female even shorter, rounded (Fig. 5). Posterior ventral angle of pronotum rounded, only slightly produced rearwards. Hind tibia slightly expanded apically. Tympanum oval; last abdominal tergite divided with acute corners either side of the midline (Fig. 3A), the hind margin with very small lobiform processes forming a minute furcula; cercus straight, strongly compressed laterally, with acute apex, shorter than the subgenital plate but exceeding the supra-anal plate. Supra-anal plate (Fig. 3A) triangular in dorsal view, somewhat elongated distally, with a rounded apex; proximally, there is a short medial longitudinal groove bounded posteriorly by a curved transverse ridge that extends across the width of the plate. Phallic complex (Fig. 4) of large size for the genus, epiphallus with large forwardly curved blade-like outer lophi (Fig. 4G, H); inner lophi absent; anterior processes of epiphallus well developed, ancorae absent (Fig. 4H). The oval sclerites have two small tubercles on their ventral surfaces. Lobular plate apparently formed from the midline fusion of a pair of bilaterally symmetrical structures, in dorsal view showing three main lobes, each of which has a concave inner surface (Fig. 4B–E).

Female. In general, similar to the male. Female particularities: medium size (average L = 24.4 mm), fastigium of vertex pentagonal and concave in dorsal view; last abdominal tergite divided but furcula absent; cercus straight in dorsal view, equal in length to the supra-anal plate or slightly shorter. Egg guide rodlike, pointed, produced rearwards, about 1/3 length of ventral valve.

The average values of P for males are 87% of those for females. After normalization, the ratios of the various body dimensions are closely similar in both sexes; in the male, the interocular space (IOS) is relatively smaller than in the female, and the antennae are somewhat longer (Table 1). In this species, the average length of the hind foot is about equal in both sexes, whereas in some other species, the foot of the male is slightly longer.

The description given here refers to the living animal (Fig. 2A, B). When dried, specimens of P. ngoylaensis lose their natural colors and become almost uniformly dark olive brown. Body multicolored in both sexes, predominantly green. Scape and pedicel of antenna green-brown, flagellum green-brown, sometimes lighter brown apically; fastigium green; vertex blue-black with black longitudinal bands either side of the midline, which extend dorsally onto the pronotum; eyes conspicuously violet in life, fading to brown when dried; upper half of frons blue-black, lower half whitish-yellow, extending posteriorly across the genae as a white-yellow subocular stripe and forming two pale patches on the ventral margin of the pronotal lobes, extending rearwards to the mesothoracic and metathoracic pleura as well. Distal margin of clypeus black; distal region of labrum, palps, and lateral margins of mandibles green. Pronotal disc multicolored, predominantly black, with two longitudinal pale bands; these bands are prolonged dorsally onto the mesothoracic and the metathoracic tergites; thoracic sterna green; hind femur green with the upper genicular lobe red; tibia and tarsi green. The first abdominal segment black, with two white-yellow longitudinal bands; the 2^nd and 3^rd segment black, sometimes slightly white dorsally; the 4^th segment green, sometimes slightly white in dorsal view; all the remaining abdominal segments green.

Cameroon: High-Nyong Division, Ngoyla, Nki National Park: 2°27'26'N, 14°34'01"E, altitude 505 m; 2°35'37"N, 14°25'58"E, altitude 498 m; 2°29'58"N, 14°23'36"E, altitude 510 m.

The eyes of Pterotiltus ngoylaensis are conspicuously violet in life, which is, to date, a unique character in the genus. The large forwardly curved blade-like outer lophi are typical of the genus and are particularly close to the structure observed in Pterotiltus coeruleocephalus Bolivar, 1905. However, P. ngoylaensis is unique within its genus in having oval sclerites with two small tubercles on their ventral surfaces. The type locality in the Nki national park (Fig. 1) bodes well for conserving its natural habitat against deforestation. However, the species may well occur more widely in southern Cameroon. Its habitat is typical of the genus: rainforest, 400 to 600 m above sea level, with abundant Marantaceae and Commelinaceae in the understory. These conditions are found in many parts of the south Cameroon plateau and neighboring countries (Congo, Gabon, and Central African Republic).

Holotype: CAMEROON • ♂; Ocean Division, Campo, Campo National Park; altitude 5 m; 13 Nov. 2017; C. Oumarou Ngoute leg.; specimen no. 2017242; MfN. Paratype: CAMEROON • 1♀; same data as holotype; specimen no. 2017243; MfN. Other material examined: CAMEROON • 4 ♂, 1 ♀; same data as holotype; personal collection of C. Oumarou Ngoute.

Cameroon, Ocean Division, Campo, Campo National Park.

Toponymic, referring to the locality of Campo, Cameroon.

Color of body as in Fig. 2C, D: multicolored, predominantly shades of red and blue-black. Average size of body: 17.92 mm (male) and 20.07 mm (female) (Table 2). Metazona of pronotum very short, about one-fifth of the length of prozona (Fig. 6E, F). Metasternal space very small, nearly closed (Fig. 6B). Apterous. Furcula of last abdominal tergite in male very small, lobiform, almost vestigial, as in Fig. 6A. Epiphallus as in Fig. 6C, D: a narrow bridge bearing a pair of large rectangular outer lophi and one or two pairs of smaller inner lophi; anterior processes of epiphallus weakly developed; small forward-pointing projections on anterior edge of bridge, which may represent the rudiments of ancorae; oval sclerites elongate and irregular in shape.

Fig. 6. 

Pterotiltus campoensis sp. nov. A. Dorsal view of male terminalia; B. Thoracic sterna; C, D. Epiphallus; C. Axial view; D. Dorsal view; E. Pronotal disc showing sulci; F. Pronotal disc showing coloration and patterning in life. Scale bar: 1 mm.

(Figs 2, 6, 7, Table 2)

Male. Body of small-medium size (L = 17.92 mm), somewhat more slender and relatively longer than the other species (L/P = 5.17, in most other species <5.0). Fastigium of vertex short, pentagonal in dorsal view, somewhat concave; frons slightly oblique; eyes large, oval, convex; inter-ocular space equal to or slightly wider than antennal scape. Pronotum (Fig. 6E, F) medial carinae absent, the space between sulci 2 and 3 longer and more convex laterally than elsewhere; metazona very short, less than one-fifth of the length of prozona (15.6% of pronotum); posterior margin of metazona slightly embayed and notched in the midline, otherwise straight; anterior margin of pronotum slightly convex; prosternal process conical, sharply pointed; mesosternal space (Fig. 6B) as wide as long; metasternal space very small, nearly closed. Wings and tegmina absent. Hind tibia not significantly expanded apically, hind femur slender (F/FD ca. 4.5) with weakly impressed chevron markings. Tympanum oval or circular; last abdominal tergite incompletely divided, the hind margin with very small thickenings suggesting a minute furcula, almost indiscernible, separation of midpoints 0.39 mm; cercus straight, extending beyond the tip of the subgenital plate (Fig. 6A). Supra-anal plate very short, triangular in dorsal view, tip rounded; proximally, there is a short medial longitudinal groove, bounded posteriorly by a transverse ridge that extends across the width of the plate (Fig. 6A). Epiphallus with a rather narrow bridge bearing a pair of large rectangular outer lophi and one or two pairs of smaller inner lophi (Fig. 6C, D). Anterior processes of epiphallus weakly developed; what may be small rudiments of forward pointing ancorae present; oval sclerites elongate and irregular in shape. Ecto- and endophalli typical of genus. The valvular plate consists of a small saddle-shaped arch with two vertical lamellae, one either side of the ventral valve (Fig. 7).

Fig. 7. 

Pterotiltus campoensis sp. nov. phallic structure. A. Endophallus and part of ectophallus after removal of the outer ectophallic sheath. The LHS cingular ramus and most of the LHS cingular apodeme has been removed to expose the endophallus. The basal endophallic valves give rise to paired narrow flexures that lead to the ventral aedeagal valves; B. Endophallus after removal of the ectophallic valvular plate and cingulum. The endophallic processes are short and terminate in spatulate endings that are appressed to ventral aedeagal sclerites, which form the greater part of the ventral aedeagal valve; C. More magnified view (scale does not apply) of the junction between the RHS endophallic process and the ventral aedeagal sclerites, viewed from the midline. The precise relations of the terminal sclerites and the membrane of the spermatophore sac are presently unclear. Scale bar: 1 mm.

Female. In general, similar to the male. Female particularities: small to medium size (L= 20.07 mm), last abdominal tergite incompletely divided but no furcula; cercus long and straight, slightly compressed laterally, tapering to an acute apex, slightly shorter than length of the supra-anal plate. Egg guide rod-like, pointed, produced rearwards for slightly more than half the length of the ventral valves.

The average values of P for the male are 85% of those of the female. After normalization, the ratios of the various body dimensions are similar in both sexes; only the interocular space (IOS) is relatively smaller in the male than in the female. Data on relative antennal length (which are significantly longer in the male in other species) are not available (Table 2). There is no difference between the sexes in the relative lengths of the hind foot.

(Fig. 2C, D) Body multicolored in both sexes, predominantly red in dorsal view; scape and pedicel of antenna green, flagellum entirely red, sometimes light brown apically; fastigium blue; vertex blue with two indistinct yellow or red lateral longitudinal bands diverging rearwards; eyes red in life, fading to yellowish-brown when dried; frons blue-black with lighter mottling on clypeus and labrum. Palps green. Genae blue-black, with a narrow yellow subocular stripe; post ocular stripe black, extending onto the pronotum. Pronotal disc multi-colored, predominantly black with two yellowish patches at the anterior margin of prozona and two more at the posterior margin of metazona, and red pigment in the midline between the yellow patches; mesothoracic tergite black with small red areas along its posterior margin either side of midline; metathoracic tergite mainly red; abdominal tergite 1 red medially with yellow pigment laterally, tergites 2 and 3 black, tergite 4 yellowish, remainder of abdomen in general blue. Thoracic and abdominal sterna blue-black; prosternal spine brownish, probably green in life. Hind femur yellowish proximally and green distally; knee blue-black with upper lobe tinged brownish, lower lobe blue; tibia and tarsi blue-black.

CAMEROON, Ocean Division, Campo: 2°20'43"N, 9°59'28"E, altitude 5 m.

Pterotiltus campoensis is most noticeable for its predominantly red and blue coloration, a unique character in the genus. The epiphallus with a pair of large rectangular outer lophi is close in this genus to Pterotiltus apicalis Bolivar, 1905 (See fig. 63 in Hollis 1975). However, P. campoensis is distinguishable by forward-pointing projections on anterior edge of bridge, which may represent the rudiments of ancorae. The new taxon is found in humid coastal forests at very low altitude (less than 15 m above the sea level). It was found both in wet areas and in the drier part of the forest, where it could be caught on young tree branches and on dead branches. We recorded the species in the Campo Ma’an National Park (Fig. 1); its natural habitat is therefore relatively well protected, despite the accelerated rate of deforestation in southern Cameroon. As with P. ngoylaensis, this species might well be found in other similar localities in south Cameroon and possibly in the neighbouring countries of Equatorial Guinea and Gabon.

Pterotiltus minimus Ramme, 1929.

Greek Para, near, close to; Pterotiltus, a genus of oxyine grasshopper, erected by Karsch, 1893.

Differs from Pterotiltus Karsch, 1893 only in the following particulars (Table 3): Size generally smaller; males average 12–14 mm in length, females 16–22 mm. Cuticle of fastigium and vertex in head and of thoracic and proximal abdominal tergites, coarsely punctate. Tegmina present but micropterous, barely exceeding the mesothoracic segment, rounded and sometimes brightly colored (Fig. 8). Female subgenital plate with two robust posteriorly directed projections, arising slightly anterior to the posterior edge, that project horizontally below the ventral ovipositor valves. Valvular plate of phallus simple, not foliose. Epiphallus with the bridge reduced, outer lophi long, upwardly and inwardly curved, either pointed and “horn-like” or bifid at their tips. Inner lophi absent or very small. Ancorae absent. The anterior processes of the epiphallic bridge, if present at all, tend to be elongated and inwardly pointed.

Fig. 8. 

Parapterotiltus minimus (Ramme, 1929). A. Typical form; B. Another individual lacking yellow markings; C. Female, typical form; D. Female lacking yellow color on the elytron.

The 3 known species are all from the Cameroonian highlands.

Holotype: CAMEROON • ♂; West-Central Tropical Africa, Bamenda; 5°95'12"N, 10°16'69"E; W. Ramme leg.; DORSA no. 000031S01; MfN. Topotype: CAMEROON • 1♂; Mezam division, Bamenda; 5°57'35"N, 10°08'50"E; altitude 1598 m; C. Oumarou Ngoute leg.; specimen no. 2017248; MfN. • 1♀; Mezam division, Bamenda; 5°57'35"N, 10°08'50"E; altitude 1598 m; C. Oumarou Ngoute leg.; specimen no. 2017247; MfN. Other material examined: CAMEROON • 1♂, 1♀; same data as topotype; personal collection of C. Oumarou Ngoute.

Cameroon, Mezam division, Bamenda.

Color of body as in Fig. 8A–D: multicolored, predominantly brown. Thoracic and abdominal terga brown, each segment usually with a single, midline yellow spot in male (Fig. 8A). Average size of body, 13.23 mm (male) and 21.59 mm (female) (Table 4). Fastigium of vertex slightly concave, sloping downwards. Pronotal medial carinae absent; metazona much shorter than prozona, making up only 17% of pronotal length; metasternal interspace very small, narrowly open; tegmina very small with rounded, almost spherical tip. Cerci compressed laterally, with acute apex not exceeding the tip of subgenital plate. Outer lophi of epiphallus long, pointed, horn-like; inner lophi absent (Fig. 9A, B); absence of anterior processes (Fig. 9A, B).

Fig. 9. 

Parapterotiltus minimus (Ramme, 1929). A. Drawing of epiphallus of holotype from Hollis 1975 (scale bar does not apply); B. Photograph from a recent dissection of a topotypic individual. Note absence of ancorae and anterior processes and the large divergent “horn-shaped” lophi that are hooked but not bifid at their tips. Scale bar: 1 mm.

(Figs 8–10, Tables 4, 7).

Male. Size of body, 13–14 mm (male) and 21–22 mm (female) (Table 4). Fastigium broadly triangular, sloping downwards, its surface slightly concave with no medial carina, its tip merging smoothly with the frontal ridge. Pronotum devoid of medial carinae. Anterior margin slightly excurved, posterior margin transverse, straight, minutely notched in midline. Metazona much shorter than prozona, making up only 17% of pronotal length. Ventral margin of lateral lobes strongly sinuate, posterior angle rounded but produced slightly rearwards. Prosternal process vertical, acutely pointed. Mesosternal interspace about as wide as long, lateral lobes rounded. Metasternal interspace very small, narrowly open. Hind femur slender, outer face with weak chevron-shaped impressions. Hind knee smooth dorsally, with no medial terminal point. Upper genicular lobes rounded, hind tibia slender. Internal hind tibial spurs somewhat larger than external spurs. Ventral face of hind tibia rather densely hirsute, dorsal face only sparsely. Arolium large. Tegmen very small (total length 0.94 mm), with rounded, almost spherical tip. Wing absent. Tympanum circular. Tenth abdominal tergite divided, furcula minute, points separated by 0.39 mm. Supra anal plate short, triangular, pointed, wider than long, not completely covering pallium. Cerci laterally flattened, wide at base, tapering to acute melanised points not exceeding subgenital plate. Subgenital plate short, rounded. Phallus with a voluminous ectophallic membrane containing a ventrolateral sclerite. Aedeagus consists only of the ventral valves and the valvular plate. This plate is, however, simple, resembling that of Oxya (Hollis 1971). The endophallic processes do not reach the exterior but end shortly after their flexure on ventral aedeagal sclerites that constitute the actual tips of the ventral valves. Epiphallus distinctive (Fig. 9), with divided bridge, long pointed “horn-like” lophi, ancorae and anterior processes absent. “Oval” sclerites present, elongate, roughly triangular.

Female. Similar to male, but much larger and more robust (L = 21.6 mm), and some differences in coloration (see below). Egg guide produced into a pointed rod lying between the bases of the ventral ovipositor valves (Fig. 10B, C). Supra-anal plate lingulate, with a rounded tip and a prominent midline depression proximally; cerci straight, slightly shorter than supra-anal plate (Fig. 10A).

Fig. 10. 

Parapterotiltus minimus (Ramme, 1929). Female terminalia. A. Dorsal view; B. Ventral view, subgenital plate and egg guide shaded; C. Lateral view, subgenital plate and egg-guide shaded; D, E. Pterotiltus impennis showing differing structure of subgenital plate in that genus, ovipositor valves slightly separated for clarity (not to same scale as A–C); D. Lateral view; E. Ventral view. Scale bar: 1 mm.

(Table 4) P male/P female is only 0.71, indicating a considerable size difference between the sexes. Once again, the male antenna is proportionately longer and the inter-ocular space smaller than in the female. The eyes are slightly more protuberant (E-E) in the male than the female. The foot formula is practically identical in the two sexes; the second tarsal segment is very short (14% of the foot) as is typical for non-arboreal grasshoppers. The entire hind foot is relatively somewhat longer in the male than the female. Note however that N, the sample size, is low in this species.

Male. Vertex, occiput, and posterior half of the genae matte black. Eyes shiny black in life, drying brown. Fastigium, frons, and anterior half of genae dull green. Basal segments of antenna and proximal flagellar segments green, distal segments orange with paler tips. Clypeus and labrum proximally green, distally black; the upper outer corners of the labrum bear two orange or bright yellow patches. Palps and outer surfaces of mandibles green.

Pronotum, thorax, and first four abdominal tergites dull brown. Lateral lobes of pronotum with ventral margins irregularly marked with pinkish orange. In some specimens, there is a small orange patch in the midline of the anterior pronotal margin. Tegmina bright yellow, contrasting strongly with the dark brown thoracic pleura. Posterior margins of first three abdominal tergites marked with orange or yellow patches in the midline. Abdominal segment 5 and all more distal segments light leaf green. Tips of cerci blackish. Fore and middle legs green but with orange femora. Hind femur green, knee black, but lower genicular lobes dark blue. Outer and inner faces of hind femur marked with two dark green longitudinal bands, converging distally. Condyle of hind tibia black, remainder of tibia green, tibial spines and spurs blue black.

Female. General impression, dull brown with green legs and tip of abdomen. Differs from male in detailed marking and in the absence of orange femora on fore and middle legs. Posterior half of gena white (tinged with pink), continuing onto ventral margin of the pronotal lobes, thus replacing the orange color of the male in this area. Frons brown, not green. The paired yellow marks on the upper margin of the male labrum are replaced in the female by a yellow central spot on the lower labrum, and the orange medial markings of the pronotum and proximal abdominal tergites are absent. Hind femora green, with darker chevron markings. Inner face of the femur with a single wide dark green longitudinal band. In some specimens, the distal femur and the hind knee are suffused with reddish brown instead of the black seen in males.

It should be noted that in both the Bamenda and the Banganté populations of P. minimus, there is marked variability in coloration between individuals, especially in the extent of orange markings on the tergites, and in some females the tegmina are not contrastingly colored (Fig. 8).

Cameroon: Bamenda (type locality): 5°57'35"N, 10°08'50"E, altitude 1598 m; Banganté: 5°09'30"N, 10°31'58"E, altitude 1325 m.

Ramme’s description referred only to the male; the female has been unknown until now. Its divergent characters, especially the female subgenital plate, have prompted a re-examination and, together with the new species described below, have led to our erection of this new genus.

The above description differs slightly from that of Ramme (1929). He wrote that the antennae are shorter than described here. His holotype (examined) had broken antennae when examined in 2016. He also described the P. minimus male as having a truncated, squared-off tip to its supra-anal plate and even illustrated this (his fig. 36) as a specific character. However, the holotype presently has a normal triangular supra-anal plate but shows an old fold line. Apparently, Ramme did not realise that the tip of the plate was folded under and probably it did not re-emerge until the specimen was relaxed by Hollis (1975), who dissected out and figured the epiphallus.

Holotype: CAMEROON • ♂; Ndé Division, Banganté; altitude 1335 m; 13 Nov. 2017; C. Oumarou Ngoute leg.; specimen no. 2017241; MfN. Paratype: CAMEROON • 1♀; same data as holotype; specimen no. 2017240; MfN. Other material examined: CAMEROON • 10♂, 5♀; same data as holotype; personal collection of C. Oumarou Ngoute.

Cameroon, Ndé Division, Banganté.

From Latin, minimoides, “similar to minimus”. Refers to the external habitus of the species, almost indistinguishable from P. minimus.

Color of body as in Fig. 11E–H: multicolored, predominantly brown. Thoracic and abdominal terga brown: each segment with two, midline yellow spots in male (Fig. 11E, F). Average size of body, 13.95 mm (male) and 17.32 mm (female) (Table 5). Fastigium of vertex flat, punctate; interocular space with a small medial depression. Medial carina of pronotum very weak or absent; metazona short, about one-third the length of prozona, and 22% of the pronotum (Fig. 12E, F); metasternal space open, about half the width of the mesosternal space (Fig. 12B). Micropterous: elytra very small, roughly circular, not extending beyond the mesothorax. Cerci strongly compressed laterally, slightly incurved, acute apex, exceeding the tip of subgenital plate. Outer lophi of epiphallus large, tilted rearwards, bifid at their tip; inner lophi absent (Fig. 12C, D), anterior processes well-developed (Fig. 12C, D).

Fig. 11. 

Parapterotiltus bamboutos sp. nov. and Parapterotiltus minimoides sp. nov. habitus. A, B. P. bamboutos male; C, D. P. bamboutos female, showing both brown and green color forms; E, F. P. minimoides male; G, H. P. minimoides female.

Fig. 12. 

Parapterotiltus minimoides sp. nov. A. Dorsal view of male terminalia; B. Thoracic sterna. C, D. Epiphallus: C. axial view; D. dorsal view; E. Pronotal disc showing sulci; F. Pronotal disc showing coloration and patterning in life. Scale bar: 1 mm.

(Figs 11, 12, Tables 5, 7).

Male. Length of body 13–14 mm; fastigium of vertex short, about twice as wide as long, roughly pentagonal in dorsal view, flat, punctate; frons slightly oblique; eyes large, oval, and convex; interocular space equal to or slightly wider than antenna scape with a small medial depression. Pronotum (Fig. 12E, F) medial carina very weak or absent; space between sulci 2 and 3 almost equal to the length of the metazona; metazona short, about one-third the length of prozona and 22% of the pronotum; posterior margin of metazona slightly embayed in the midline. Anterior margin of pronotum slightly convex; micropterous: elytra very small, roughly circular, not extending beyond the mesothorax laterally, not touching at the dorsal midline; prosternal process conical and pointed; mesosternal space (Fig. 12B) as wide as long; metasternal space open, about half the width of the mesosternal space; hind femur slender (F/FD = 4.5). Internal tibial spurs twice as long as external spurs. Tympanum oval; last abdominal tergite incompletely divided (Fig. 12A), the hind margin with very small lobiform processes forming a minute furcula near the midline; cercus long, slightly incurved, strongly compressed laterally with acute apex, extending beyond the subgenital plate; supra-anal plate triangular in dorsal view with acute apex; there is a short medial groove proximally bounded posteriorly by a traverse ridge that extends across the width of the plate. Subgenital plate short, rounded. The phallus valvular plate is relatively simple, with a short quadratic “anvil-like” process dorsally and paired processes distally. Epiphallus (Fig. 12C, D) remarkable, with large backwardly tilted bifid outer lophi and well-developed anterior processes; “oval” sclerites of irregular strap-like shape.

Female. In general, similar to the male. Female particularities: Length of body 15–18 mm; the last abdominal tergite divided, but the hind margin lacks a furcula; cercus is long and straight, compressed laterally with acute apex, equalling or slightly exceeding the supra-anal plate; supra-anal plate triangular in dorsal view, elongated, the apex rounded. Ovipositor valves slender and straight, upper surface of dorsal valves slightly grooved.

P male/P female = 0.79. After normalisation using this factor, it is seen (Table 5) that the male has proportionately much longer antennae and very slightly more protuberant eyes.

(Fig. 11E–H).

Body multicolored in both sexes, predominantly brown in dorsal view. Antennal scape and pedicel green, flagellum mostly brown but green basally and sometimes yellow apically; fastigium of vertex green; vertex green-blue or black; eyes black in life, turning brown or brown-yellow when dried; frons green; genae green-blue or black. Pronotal disc brown, with two yellow patches in the anterior part of prozona and two more (sometimes confluent) in the posterior part of metazona; pronotal lateral lobes mainly brown, but in life with two prominent yellow patches at the anterior and posterior ventral angles, sometimes confluent to form yellow ventral stripe that can extend on to the mesothoracic and metathoracic pleura; these yellow markings tend to fade to brown in dried specimens. Elytra yellow; mesothoracic and metathoracic tergites brown; fore and middle femora brown; hind femur green, hind knee blue with a black upper lobe, tibia and tarsus green. Abdominal tergites 1 and 2 brown with two yellow patches at the posterior margin; tergite 3 entirely or only laterally blackish; in the latter case, the medial part is brown. All other abdominal segments green.

Cameroon: Makénéné: 4°53'58"N, 10°47'59"E, altitude 790 m; Bangangté: 5°09'030"N, 10°31'58"E, altitude 1325 m; Bamenda: 5°57'35"N, 10°08'50"E, altitude 1598 m.

Parapterotiltus minimoides is almost indistinguishable from Parapterotiltus minimus in coloration, hence its specific name. Typically, they differ only in the number and placement of yellow spots on the thoracic and abdominal terga in males: in P. minimus, each segment normally has only a single, midline yellow spot, whereas the spots are paired in P. minimoides. However, there is considerable individual variation. Morphologically, the two species are more distinct: the metazona is shorter in P. minimus (17% of pronotal length) than in P. minimoides (22% of the pronotum length). In minimus, the metasternal interspace is very small and narrowly open, while this space is clearly open in minimoides, at about half the width of the mesosternal space. The cerci of minimus are shorter, not exceeding the tip of subgenital plate, while the cerci extend beyond the tip of subgenital plate in minimoides. The epiphalli, however, are dramatically different. P. minimoides is unique within its genus in having large backwardly tilted bifid lophi, carried on a fairly wide bridge with well-developed anterior processes. In P. minimus, the bridge is reduced in size, anterior processes are absent, and the lophi are long but simple, pointed, and horn-like. Unexpectedly, these two outwardly very similar species occur together at some localities (Banganté and Bamenda) between 1000 and 1600 m of altitude (Fig. 1).

Holotype: CAMEROON • ♂; Bamboutos Division, Mount Bamboutos; altitude 2400 m; 15 Nov. 2017; C. Oumarou Ngoute leg.; specimen no. 2017246; MfN. Paratype: CAMEROON • 1♀; same data as holotype; specimen no. 2017245; MfN. Other material examined: CAMEROON • 2♂, 4♀; same data as holotype; personal collection of C. Oumarou Ngoute.

Cameroon, Bamboutos Division, Mount Bamboutos.

Toponymic, referring to the Mount Bamboutos, Cameroon.

Color of body as in Fig. 11A–D: multicolored, predominantly black in male and olive-brown or green in female. Thoracic and anterior abdominal terga black: each segment with two midline yellow spots in male (Fig. 11A, B). Average size of body 12.74 mm (male) and 16.83 mm (female) (Table 6). Fastigium of vertex slightly concave. Pronotal medial carina very weak or absent; metazona short, accounting for only 19.5% of the length of pronotum (Fig. 13E, F); metasternal space open, about half the width of mesosternal space (Fig. 13B). Micropterous: elytra minute, rounded, barely exceeding the mesothoracic segment. Cerci strongly compressed laterally, slightly incurved, acute apex, extending beyond the tip of the supra-anal plate and sometimes exceeding the tip of the subgenital plate as well. Outer lophi of epiphallus large, horn-like, and pointed; a single weak pair of inner lophi (Fig. 13C, D); anterior processes absent (Fig. 13C, D).

Fig. 13. 

Parapterotiltus bamboutos sp. nov. A. Dorsal view of male terminalia; B. Thoracic sterna; C, D. Epiphallus: C. Axial view; D. Dorsal view; E. Pronotal disc showing sulci; F. Pronotal disc showing coloration and patterning in life. Scale bar: 1 mm

(Figs 11, 13–15; Tables 6, 7)

Male. Average length of body 12.7 mm; fastigium of vertex short, roughly pentagonal in dorsal view, slightly concave in the middle; frons slightly oblique, frontal ridge shallowly sulcate; eyes large, convex, interocular space equal to or slightly wider than antenna scape. Pronotum (Fig. 13E, F) medial carina very weak or absent; the space between sulci 2 and 3 almost equal to the metazona in length; metazona short, accounting for only 20% of the length of pronotum; posterior margin of metazona slightly convex in female and slightly notched in midline in the male. Anterior margin of pronotum slightly convex; prosternal process conical, vertical, and pointed; mesosternal space (Fig. 13B) as wide as long; metasternal space open, about half the width of mesosternal space; micropterous: elytra minute, rounded, barely exceeding the mesothoracic segment. Hind femur slender, 4.7 times longer than wide (Table 6). Paired internal tibial spurs nearly twice as long as the external spurs. Tympanum oval or circular; last abdominal tergite divided (Fig. 13A), the hind margin with very small lobiform processes forming a minute furcula, almost invisible, tips separated by 0.45 mm; cercus strongly compressed laterally, long, slightly incurved, with acute apex extending beyond the tip of the supra-anal plate and sometimes exceeding the tip of the subgenital plate as well; supra-anal plate triangular in dorsal view, very short, the apex angular. Proximally in the supra-anal plate, there is a short medial longitudinal groove bounded posteriorly by a curved transverse ridge that extends across the width of the plate. Epiphallus (Fig. 13C, D) with a reduced bridge and very large, horn-like pointed outer lophi and a single weak pair of inner lophi, ancorae absent.

Female. In general, similar to the male. Female particularities: Length of body 16–18 mm, posterior margin of metazona slightly convex; last abdominal tergite short, divided, but the hind margin without a furcula. Cercus slightly compressed laterally, long, straight with acute apex, equalling or slightly exceeding the supra-anal plate; supra-anal plate triangular in dorsal view, elongated, the apex lingulate and rounded. Dorsal ovipositor valves laterally compressed with rounded tips, upper surface of dorsal valves slightly grooved; ventral valves slender and straight, rodlike. Egg guide rod-like, projecting below ventral valves, acutely pointed (Fig. 14).

Fig. 14. 

Parapterotiltus bamboutos sp. nov. Female terminalia to show subgenital plate and egg-guide (shaded). The ovipositor valves have been slightly separated for clarity. Scale bar, 1 mm.

P male/P female = 0.76. Antennae of male are much longer than those of the female, and the male also has slightly longer feet, more protuberant eyes, and a smaller interocular space.

(Fig. 11A–D).

Male. Body multicolored, predominantly black; scape and pedicel green, flagellum green proximally with more apical segments orange or brown. Fastigium green to blackish green; vertex black, tinged with green in life; eyes black in life, fading to brown or brown-yellow when dried. Frons in male green above medial ocellus and white below; genae black in upper half and white in inferior half. Pronotal disc black with two yellowish patches at the anterior margin of prozona and two more at posterior margin of metazona. Elytra yellow or whitish; mesothoracic and metathoracic tergites black. Pronotal lateral lobes black, with a ventral whitish stripe prolonging the white genal stripe and continuing on to the mesothoracic pleura. Fore and middle femora orange-brown, tibiae and tarsi green in life, fading to brown or green-brown when dried; hind femur dark green; hind knee black, with the upper lobe black, lower lobe very dark green; hind tibia and tarsus greenish, condyle of tibia black. Tergites of abdominal segments 1, 2, and 3 black, with paired yellow patches at their posterior margins; 4^th abdominal tergite black in the anterior part, otherwise green; all other abdominal segments green.

Female. Green or brown (either a polymorphism or a polyphenism). Body multicolored, predominantly olive-brown or green. Scape and pedicel green, flagellum green with apical segments orange or brown; fastigium brown-green or green. Vertex black or brownish green with two ill-defined paler brown longitudinal bands running behind the eyes; eyes black in life, fading to brown or brown-yellow when dried. Frons entirely brown or green; genae black or green in upper half and light brown in inferior half. Pronotal disc brown-green or green. Elytra brown or orange; mesothoracic and metathoracic tergites brown-green or green. Fore and middle femora brown or green, tibia and tarsus green in life fading brown or green-brown when dried; hind femur entirely olive-brown in brown females; in green female, femur brown apically while basal part is green; hind knee brown, with the upper lobe black; hind tibia and tarsus blue in both color forms. Abdomen entirely brown-green or green.

Mount Bamboutos: 5°43'60"N, 10° 4’ 0’’ E, altitude 2400 m. P. bamboutos is known, at the moment, only from Mount Bamboutos (Fig. 1), hence its specific name. The population there is very small, and it is difficult to find a male in the field. Mount Bamboutos is one of the most degraded mountains in Cameroon; its human populations have destroyed almost all the pockets of forests present on the mountain and replaced them with crops. Conservation measures are urgent for the habitat of this species, which may be endemic to this mountain. However, Mount Bamboutos belongs to the volcanic line of Cameroon. It is possible that this species also occurs at altitude (more than 2000 m above sea level) elsewhere in that line, for example on Mounts Kupe and Manengouba, which are not far from the type locality. A photograph from Mt. Kupe taken by Dr. Ulf Bjelke supports this suggestion (Fig. 15).

Fig. 15. 

Parapterotiltus sp., probably P. bamboutos sp. nov., photographed on Mt. Kupe by Dr. Ulf Bjelke in 2010. This picture is the best evidence to date that this species is not confined to Mt. Bamboutos.

Parapterotiltus bamboutos and Parapterotiltus minimus are superficially very different. Body is predominantly brown in both sexes of P. minimus, while it is blackish in males and olive-brown or green in females of P. bamboutos (Table 7). However, the two species are similar in other respects, and here, we summarize the morphological differences: The metazona is shorter in P. minimus (17% of pronotal length) than in P. bamboutos (20% of pronotum length). In minimus, metasternal interspace is very small and narrowly open, while this space in bamboutos is clearly open, about half the width of the mesosternal space. The cerci of minimus are shorter, not exceeding the tip of the subgenital plate, while the cerci are longer in bamboutos, extending beyond the tip of the supra-anal plate and sometimes exceeding the tip of the subgenital plate (Table 7). The epiphallus of P. bamboutos is similar to that of P. minimus (Ramme, 1929). Both species have long horn-like pointed outer lophi, but P. bamboutos is unique within the genus for having an additional pair of weak inner lophi that are absent in minimus.