Ctonoxylon atrum Browne, 2024

Jordal, Bjarte H., 2024, An integrated taxonomic revision of Ctonoxylon (Coleoptera, Curculionidae, Scolytinae) reveals new Malagasy species originating from multiple recent colonisations of the island, ZooKeys 1203, pp. 95-130 : 95-130

Ctonoxylon atrum Browne stat. rev.

Figs 68 , 71 , 74

Ctonoxylon atrum Browne, 1965: 190 .

Type material.

Holotype, male: Nigeria, Idanre [GIS: 7.12, 5.10], 30. 9. 1964, ex Canthium [ NHMUK].

Diagnosis.

Length 3.4 mm. 2.1–2.2 × as long as broad; colour pitch black. Male and female frons slightly impressed and impunctate on lower half, finely granulated above with short scattered setae; eye parts separated by 2 / 3 the size of upper half; anterior lateral margin of prothorax with elongated groove near procoxa; propleural pit present just above procoxa; pronotum with large and deep irregular punctures; elytral suture buckled at midlength, strial punctures longitudinally elongated, subquadrate; interstriae rough, with irregular punctures and rugosities; elytral apex emarginated; interstrial vestiture of confused rows of short, black, scale-like setae.

Distribution.

Ghana, Cameroon (new country).

New record.

Cameroon, Limbe, Ekande [GIS: 4.081, 9.172], 19. Nov. 2007, ex water liana, B. Jordal, leg [1, ZMUB] .

Remarks.

This species is rather similar to C. methneri and was synonymised with C. hamatum by Schedl (1970). However, C. atrum is darker, with shorter elytral setae, the strial punctures are narrowly elongated and more separated, and the pronotal punctures are larger. It is genetically clearly separated from C. methneri and instead forms a sister relationship with C. quadrispinum sp. nov. (Fig. 11 ).

Figures

Figures 66–74. Dorsal, lateral, and front views of 66, 69, 72 Ctonoxylon quadrispinum female holotype 67, 70, 73 Ctonoxylon methneri male, and 68, 71, 74 Ctonoxylon atrum female holotype.

Figures 10–11. Phylogeny of Ctonoxylon. Node support is given as posterior probabilities above and parsimony bootstrap values below nodes 10 tree topology resulting from the parsimony analysis of 14 morphological characters for all species using implied weighting (Goloboff et al. 2018) 11 partial tree topology redrawn from a previously published Bayesian tree topology based on 1958 nucleotide position from three gene fragments (Jordal 2023). Species found in Madagascar marked in purple.