Derelomus prochesi Haran, 2025

Derelomus prochesi Haran sp. nov.

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Fig. 11E–H View Fig

Diagnosis

Derelomus prochesi sp. nov. can be distinguished from other species of the genus by the combination of appendiculate claws, a rostrum longer than the pronotum in lateral view, the metanepisterna with a dense vestiture of white scales and the recumbent setae on the elytra. It is closest to D. setifer sp. nov. but the latter species bears erect setae on the elytra. The penis of both species is diagnostic ( Fig. 11C, G View Fig ). GenBank accession numbers for the corresponding DNA barcodes: ON553431 View Materials –32/PV598482.

Etymology

The species is dedicated to Şerban Procheş, for his intensive collecting of weevils in the Republic of South Africa that enabled the discovery of this species and its host plant.

Material examined

Holotype

REPUBLIC OF SOUTH AFRICA • ♂; “Rep. of South Africa; WC Pr. [ Western Cape Province], Tradouw Pass ; 20.viii.2023; J. Haran coll.” “ JHAR05978-01 ; -33.931 20.712 [33°55′53″ S 20°42′43″ E]; Kiggelaria africana fl.; Collection – Cirad” “Holotype; Derelomus ; prochesi ; Haran 2025”; SAMC.

GoogleMaps

Paratypes

REPUBLIC OF SOUTH AFRICA – Western Cape Province • 1 ♀; Tradouw Pass; 33°55′53″ S, 20°42′43″ E; 20 Aug. 2023; J. Haran coll.; beating male inflorescences of Kiggelaria africana L.; JHAR05978-02 ; CBGP GoogleMaps • 3 ♀♀; Stellenbosch Mountain ; 33°57′36″ S, 18°52′48″ E; 17 Jul. 2018; J. Haran coll.; beating fynbos; JHAR01174 ; CBGP GoogleMaps • 1 ♀; Kirstenbosch botanical garden , entrance area; 33°59′14″ S, 18°26′00″ E; Sep. 2010; Ş. Procheş coll.; flowers of Kiggelaria africana ; JHAR07403-01 ; CBGP. GoogleMaps – Eastern Cape Province • 2 ♀♀; Colchester; 33°41′24″ S, 25°49′48″ E; 1 Oct. 2020; Ş. Procheş coll.; flowers of Kiggelaria africana ; JHAR07404 ; CBGP. GoogleMaps

Description

Male

MEASUREMENTS. Body length 2.0 mm.

COLOR. Body integument pale brown; vestiture of elytra made of a row of white recumbent setae non-contiguous on each interstria, shorter than width of interstriae; each puncture of striae with a short recumbent seta, shorter than width of interstriae; setae not concealing the integument.

HEAD. Rostrum longer than pronotum in lateral view (1.2×), moderately and regularly downcurved; in dorsal view 5× as long as wide, integument densely punctate, covered with short recumbent whitish setae oriented transversally, except near eyes where oriented toward forehead; antennae inserted near apical 1/5 of length; head capsule coarsely punctate in dorsal view, with contiguous suberect and downcurved whitish setae oriented toward centre of forehead; eyes convex, exceeding lateral curve of head capsule in dorsal view; antennal funicle with first segment 2× as long as wide, equal in length to segments 2–4 together, 3 isodiametric, 4–7 transverse.

PRONOTUM. Wider than long (W: L ratio: 1.26), widest near apical ⅓ of length, 0.75 × as wide there as elytra at humeral angles, side rounded, abruptly converging in apical ⅓, apical constriction shallow; integument with large circular punctures, space between punctures smooth, shiny, as wide as or narrower than diameter of punctures; setae recumbent, downcurved, shorter than diameter of punctures in central area, oriented toward scutellar shield.

METATHORAX. Metanepisterna with dense vestiture of white scales.

ELYTRA. Moderately longer than wide (W: L ratio: 0.75); sides convex, widest near middle of length; humeri raised; apex jointly rounded, slightly notched at apex of suture; striae with punctures as wide as or slightly wider than interstriae; interstriae slightly convex, 9 raised into carina; scutellar shield triangular, densely covered by recumbent whitish setae.

ABDOMEN. Underside covered with minute recumbent whitish setae, not contiguous. Stridulatory plate with lines of 4–6 granules ¾× as long as median line from base. Central sclerotized area narrowed near base.

LEGS. Profemora moderately thickened near middle of length; protibiae with external margin straight, internal slightly concave in apical ½, metatibiae slightly curved outward in apical half; claws appendiculate.

TERMINALIA. Body of penis elongate (W:L ratio: 0.20), 2× as long as apodemes; sides concave in middle of length in dorsal view, widest at base, apical ½ lanceolate, apex rounded; in lateral view curvature stronger in basal ⅓ of length, width narrowing regularly from middle of length to apex; apex curved upward ( Fig. 11G View Fig ).

Sexual dimorphism

Females can be distinguished from males by the rostrum which is narrower and longer in dorsal view (7× as long as wide in females, 5 × as long as wide in males).

Life history

Derelomus prochesi sp. nov. was collected in almost all localities on flowers of the tree Kiggelaria africana ( Achariaceae ), which probably constitutes its host plant. This species forms a supported phylogenetic clade with Derelomus pallidus ( Fig. 33 View Fig ) associated with Euclea racemosa ( Ebenaceae ). Such clade exhibits a derived condition of development on dicot plants from an ancestral association with palms ( Arecaceae ) in the genus Derelomus . The flowers of Euclea spp. and Kiggelaria africana show remarkable morphological similarities, possibly arising from convergently selected features to host weevils. More generally, Kiggelaria trees agree in several aspects with the trends of brood-site pollination mutualism with weevils (dioecy, patchy distribution, cantharophilous flowers; Haran et al. 2023a). Such an interaction would deserve detailed investigations. Adults were collected from July to October.

Distribution

Derelomus prochesi sp. nov. is a South African endemic in our current knowledge, distributed along the coast of the Eastern and Western Cape provinces, up to 40 km inland. Its host ranges naturally from Cape Town in the Republic of South Africa up to Kenya (GBIF 2024).