Pterotiltus miniatulus Karsch 1893
Creators: name: Rowell, C. H. F.
name: Oumarou-Ngoute, Charly
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Acrididae
Pterotiltus
Pterotiltus miniatulus

description: 3. Pterotiltus miniatulus Karsch, 1893
Figs 12–14; Table 3
Pterotiltus miniatulus Karsch, 1893: 108.
Pterotiltus miniatulus – Kirby 1910: 387. — Ramme 1929: 312. — Johnston 1956: 259. — Dirsh 1965: 236. — Hollis 1975: 226, fig. 65. — Mestre & Chiffaud 2006: 245. — Hollier 2010: 19 (one male syntype – now a paralectotype – in Geneva Museum – not examined for this study).
non Pterotiltus miniatulus – Bolívar 1905: 226 (misidentified; we describe this specimen below, p. 92, as P. biafrensis sp. nov.).
Type material
Lectotype (designated here)
TOGO • ♂; Bismarckburg [nr Yégué]; [8.1833° N, 0.6833° E]; Jan. 1891; R. Büttner S. leg.; MfN 5595, DORSA 000805S01.
Paralectotypes
TOGO • 3 ♂♂; Bismarckburg [nr Yégué]; [8.1833° N, 0.6833° E]; 20 Sep.–15 Oct. 1890 and 1 Jun.– 15 Jul. 1891; R. Büttner S. leg.; MfN, DORSA 000805S02 to DORSA 000805S04 • 2 ♀♀; same data as for preceding; 1 Jun.–15 Jul. 1891; MfN, DORSA 000805S05, DORSA 000805S06.
Other material examined
GHANA • 1 ♂; Volta Region, 2 miles E of Chiare [probably a misspelling of Shiare]; [8°18′ N, 0°36′ E]; 23 Dec. 1963; N.D. Jago leg.; NHMUK • 1 ♂; Volta Region, 6 miles S of Nkwanta; [latter at 8°16′0″ N, 0°31′0″ E]; 23 Dec. 1963; N.D. Jago leg.; NHMUK.
Description (made from the lectotype and paralectotypes; Figs 12–14)
Of medium size for the genus (see measurements in Table 3).
Male
HEAD. Antennae mostly black, but greenish at base and minutely tipped with yellow at the extreme tip. Frons, frontal ridge and genae yellow (possibly white in life?) densely sprinkled with black pitting. Labrum and outer face of mandibles, black. Fastigium, vertex, occiput, and post-ocular stripe, black.
Palps yellow, probably green in life.
THORAX. Pronotum, thoracic and proximal abdominal segments with ground colour shiny black. Anterior margin of pronotum blotched with golden yellow; metazona and posterior ventral angle entirely yellow. Tegmina and wings absent. In dried specimens the femora of all three pairs of legs are dull orange or yellow (they were also so described by Karsch 1893); tibiae and tarsi, however, are green, and the femora too may well be green in life. The (comparatively fresh) Ghanaian specimens have blue-green tibiae (Fig. 13), and the mesothoracic legs are greenish. Fore legs and hind femora, however, are orange, as in older material. Hind knee and most proximal part of hind tibia red. Hind tibiae pale blue green and are progressively expanded laterally over the distal ⅔ of their length.
ABDOMEN. First 4 abdominal tergites black, decreasing in intensity towards the rear. Posterior margin of 1 st abdominal tergite and all intersegmental membranes yellow. Abdominal tergites 5 & 6 yellowish, tergite 7 to tip of subgenital plate red. Cerci green, narrowing progressively to a finely pointed conical tip.
PHALLIC COMPLEX. All the males in the type series are immatures, apart from one (DORSA 000805S04) which is an intersex, probably as a result of nematode parasitism (see Rowell 2000), and so were unsuitable for a phallic preparation. Two non-type males from Ghana were obtained from the NHMUK for phallic dissection – one had no phallus (previously extracted), the other was relaxed and the phallus successfully extracted. Epiphallus (Fig. 14C) of the usual Pterotiltus type, but with only outer lophi, that are slim, pointed and forwardly curved. No inner lophi present. The ‘oval’ sclerites of epiphallus are L-shaped, bridge is rather narrow, ancorae absent.
Female
Closely similar to male in colouration and pattern, but the red colour of the posterior abdomen less clearly demarcated and less brilliant.
Distribution
Mestre & Chiffaud (2005) list Ghana, Togo and Nigeria as the distribution of miniatulus, but we know of no evidence that it occurs in Nigeria. All confirmed recorded specimens come from a small area on the Ghana / Togo border zone, roughly between Nkwanta (Ghana) and Yégué (Togo).
In the literature, however, it has been recorded not only from Togo (Karsch 1893) and northeastern Ghana (Jago 1968), but also from the continental part (Rio Muni) of Equatorial Guinea (Bolívar 1905). This suggests a surprisingly disjunct distribution!
However, Bolívar (1905) identified the Equatorial Guinean specimen on the basis of Karsch’s published description only without examining it, and wrote:“Solo existe un macho que parece referirse bien a la especie citada”. This specimen (a male), with Bolívar’s label, is preserved in the Madrid museum (Fig. 54). Examination shows that it differs from the West African miniatulus in its phallic structures and in colouration. We conclude that it is is not miniatulus but an undescribed species of the genus, and we describe it below (p. 92) as P. biafrensis sp. nov. Accordingly, the distribution of miniatulus is properly just E Ghana and W Togo. The Equatorial Guinean record is erroneous.
Designation of lectotype
We here designate as lectotype the specimen shown in Figs 12–13; male, DORSA 000805S01, in MfN.
Status of taxonomic material
Adequate, both sexes known, but needs more collection of fresh specimens and a description of colouration in life.
description: Published as part of Rowell, C. H. F. & Oumarou-Ngoute, Charly, 2025, Review of Pterotiltus Karsch, 1893 (Orthoptera, Acrididae, Oxyinae), pp. 1-104 in European Journal of Taxonomy 986 on pages 22-27, DOI: 10.5852/ejt.2025.986.2853, http://zenodo.org/record/15235428