Trichoderolus Vitali, 2025, n. gen.
Creators: name: Vitali, Francesco
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Cerambycidae
Trichoderolus

description: Trichoderolus n. gen.
Fig. 7
Type-species. Tapinolachnus gyllenhalii Fåhraeus, 1872 (monobasic).
Material examined. 1♂, D[eutsche] Ost Afrika, Lindi, [19]03, Kormawachamus Gyllenhali Fåhr. det. E. Hintz (3816a), E. Hintz don. 1923, MNHNL115655; 1♂ [Tanzania,] Lukuledi, Kormawachamus Gyllenhali Fåhr. det. E. Hintz 1916 (3816b), E. Hintz don. 1923, MNHNL115656; 1♂, 1♀, Nord Mozambico, Cuamba, 14,49 S, 36,33 E, 10–20.IX.[19]99, G. Curletti leg., CFV; 3♂♂, 1♀, Zimbabwe, Matabeleland South, Matobo N. P., Big Cave Camp, 20.504801 S / 28.441385 E, 1275 m, 24–25.XI.2016, H. Sulak, A. Prozorov & R. Yakovlev leg., CFV.
Diagnosis. Body flattened, elongated. Head with gently depressed interantennal space, followed by a short fovea between the upper eye lobes; these small and well separated between them; intergenal furrow straight. Antennae long, twice as long as body in male, ectoapically toothed from antennomere V and endoapically covered with long raised pubescence; scape slightly convex externally, covered with short, raised pubescence. Pronotum elongated, without lateral spines, dorsally almost flat, smooth on the centre of the disc, crossed with a V-shaped furrow, in turn crossed by almost regular transversal wrinkles. Elytra parallel-sided in both sexes, rounded at apex; elytral pubescence dense, giving changing pattern. Procoxal cavities rounded; tibiae not ridged ventrally; femora longitudinally ridged ventrally.
Differential diagnosis. Trichoderolus n. gen. belongs to the genera characterized by ventral side of femora longitudinally ridged, differing in the antennae covered with raised pubescence.
Fåhraeus (1872) originally described the type-species in the genus Tapinolachnus Thomson, 1865. Some years later, Olliff (1889) described another species, afterward considered as a junior synonym of T. gyllenhalii, in the genus Tapinolachnus as well. This Asian genus shows in fact similar characters: antennae long, covered with raised pubescence; pronotum elongated, without lateral spines, dorsally almost flat, elytra almost parallel-sided in both sexes, tibiae not ridged and femora ridged ventrally. However, in Tapinolachnus, the pronotum does not show a V-shaped furrow but two longitudinal furrows delimiting a smooth field as in many Australasian Cerambycini; the head is nearly smooth between the eyes; the mouthparts are more elongated and the neck much shorter; the antennae are ectoapically toothed from antennomere IV; the elytral apex is toothed at both sides and the tibiae do not show longitudinal ridges.
Gahan (1891) transferred T. gyllenhalii to Derolus Gahan, 1891, which he considered as a subgenus of Pachydissus Newman, 1838. Aurivillius (1908) considered Derolus as a true genus and T. gyllenhalii has been classified as such until now. However, beside the pubescent antennae, Trichoderolus n. gen. differs from Derolus in the tibiae without ridges and in the longer antennae in male (at most, one-third longer than body in Derolus males).
Concerning the only African genera with ridged femora (Adlbauer, 2006a, 2006b, 2009), Trichoderolus n. gen. differs from Diorthus Gahan, 1891 in the scape without apical cicatrix; from Ptycholaemus Chevrolat, 1958 in the tibiae without ridges, the coarsely faceted eyes, the open mesocoxal cavities and from Spiniderolus Lepesme & Breuning, 1958 in the longer, unarmed antennae in males. From those genera showing small body-size and antennae as long as or shorter than body in males, it differs from Sudreana Adlbauer, 2006, Dissaporus Aurivillius, 1906 and Microderolus Aurivillius, 1925 in the pronotal V-shaped furrow, from Graciliderolus Lepesme & Breuning, 1958 in the fusiform femora and from Djabiria Duvivier, 1891 in the slender habitus and the matte integument.
Finally, the pubescent antennae of Trichoderolus gyllenhalii (Fåhraeus, 1872) n. comb. are reminiscent of many species in the Asian genus Dialeges Pascoe, 1856, which principally differ in the tibiae not ridged ventrally, the pronotal disc with a pair of longitudinal furrows and the shorter antennae.
Derivatio nominis. From the Old Greek “ Trichos ” (hair) and the genus Derolus in reference to the pubescent antennae. Gender masculine.
Remarks. Interestingly, Eugene Hintz identified both males belonging to the MNHNL as “ Kormawachamus Gyllenhali ” in 1916. Thus, this German entomologist did not agree with the taxonomy in use and had planned to separate this species in a new genus dedicated to “Kormawa,” a family name widespread in Tropical Africa. Unfortunately, the arrival of WWI and the subsequent end of his entomological activity (Juhel & Vitali, 2011) did not allow him to complete this publication.
description: Published as part of Vitali, Francesco, 2025, Notes, transfers, new combinations, and new taxa of some African genera of the tribe Cerambycini (Coleoptera Cerambycidae), pp. 20-28 in Zootaxa 5620 (1) on pages 22-23, DOI: 10.11646/zootaxa.5620.1.2, http://zenodo.org/record/15218963