Pterotiltus nigroantennatus Bolivar 1908
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 nigroantennatus

description: 7. Pterotiltus nigroantennatus Bolívar, 1908 nom. rev. et stat. nov.
Figs 17–18; Table 5
Pterotiltus inuncatus var. nigroantennata Bolívar, 1908: 106. Erroneously synonomized with apicalis by Ramme 1929: 315 and by Johnston 1956: 258.
Type material
Holotype
DEMOCRATIC REPUBLIC OF THE CONGO • ♂; Kwango Province, Popocabacca; [5°42′ S, 16°35′ E]; F. Loos leg.; RBINS.
Other material examined
DEMOCRATIC REPUBLIC OF THE CONGO • 1 ♂; Haute Tshuapa, Yolo; Jun. 1937; Buckinckx leg.; RMCA.
Description (see Fig. 17)
Bolívar’s 1908 description is a very short note: in its entirety, it reads: “A P. inuncato colore tantum differt: antennis nigris, capite superne omnio fusco olivaceo; pronoti lobis lateralibus fascia extern flava medio interrupta, pedibus viridibus. Statura (male) paulo majore. Loc.: Popocabacca (F. Loos)”.
This specimen differs from all other “ apicalis ” s. lat. specimens in several aspects of colouration, especially its strikingly shiny black antennae (unfortunately broken), and in its epiphallic structure (Fig. 18A); it is also somewhat larger than the Ossidinge holotype of rubroantennatus. The valvular plate of this individual is of a common type, with a pair of vertical medial lobes, and sheathing concave lateral lobes. The ventral aedeagal sclerites are robust, laterally compressed, and apparently hollow – at least at their tips. It differs in other ways from the Cameroon populations – light markings in deep yellow (we think not just discoloured white), similar to those of the Faradje specimen (see Fig. 56 below) and has a completely yellow pronotal metazona, with no black pigment in its lateral region. Its darker pigmentation is green rather than black. Like the Ossidinge type it has a red tip to the abdomen.
Measurements
See Table 5.
Taxonomic remarks
The P. nigroantennatus holotype (Figs 17, 18A) bears an ID label of Ramme allotting it to P. apicalis. Ramme had in Berlin Karsch’s type series of P. inuncatus, so was able to compare the two species, and (Ramme 1929: 315) wrote correctly: "Bolívar’s P. inuncatus nigroantennata has nothing whatever to do with Karsch’s inuncatus ”. He labelled it apicalis (Fig. 17C) and speculated that it might be the male of P. apicalis from Bioko, the unique holotype of which is a female.
The holotype seems to be the specimen from DR Congo attributed to apicalis by Dirsh (1970): it is from the same locality, Popokabaka, and the same collector (F. Loos), though he makes no reference to Bolívar or his name for this taxon. Dirsh (1966) also mentions a specimen of “ apicalis ” from Chingufo, Angola (7°37′ S, 20°32′ E) – unfortunately the present authors have not been able to trace this specimen. These are some of the very few published records of the genus from the southern side of the Congo Basin. We here remove this species from synonomy with apicalis, under the name P. nigroantennatus Bolívar, 1908 nom. rev., stat. nov.
There is a possible second male specimen of this taxon, labelled “unidentified Pterotiltus ”, ID Dirsh, (examined) (Fig. 18B). The locality for this specimen, “Yolo”, is possibly Yalola, on the Tshuapa River [00°13′ S, 23°13′ E]. Or it may be Yolonga, also on the Tshuapa [1°S, 22°41′ E]. These localities are also on the south bank of the Congo River, though a long way from Popokabaka, and much more northern. There is a better-known locality called Yolo in the DRC, an urban district of Kinshasa, but this locality is excluded by the specimen label, which specifies Haute Tshuapa.
The epiphalli of the Yolo and Popokabaka specimens are very similar (see Fig. 18), as is the general green and yellow colouration and the red abdomen. Unfortunately, the Yolo specimen lacks almost all of its antennae, so it cannot be determined whether it had the same eponymous shiny black flagella as the Popokabaka specimen. As this specimen is a unique example, we did not further dissect its phallus to examine the valvular plate or the ventral aedeagal sclerites, which might have given more information about its possible identity.
Status of taxonomic material
Poor. The female of this taxon is unknown, and the unique male holotype is damaged. Needs further collection.
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 33-36, DOI: 10.5852/ejt.2025.986.2853, http://zenodo.org/record/15235428