Derelomus crypticus Haran, 2025

Derelomus crypticus Haran sp. nov.

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Fig. 29 View Fig

Diagnosis

In the D. ephippiger group, this species can be distinguished by the comparatively strong curvature of the rostrum in lateral view ( Fig. 29B–C View Fig ) and the sides of the elytra moderately convex in males in dorsal view. This species is very close to and sympatric with D. bivirgatus but the latter is larger and has a longer rostrum ( Fig. 28A–C View Fig ). The new species is genetically well distinguished from D. bivirgatus ( Fig. 34 View Fig ). GenBank accession number for the corresponding DNA barcode: ON553424 View Materials .

Etymology

The specific epithet refers to the cryptic nature of this rare species. Specimens were first identified as aberrant forms of D. bivirgatus and the use of molecular data was critical for its recognition as a distinct species.

Material examined

Holotype

KENYA • ♂; “ Mac Arthur ; Makindu [Kenya, 2°16′37.2″ S 37°49′08.4″ E] 5 37 [ May 1937]” “Press by; Com Inst Ent; B.M. 1981-315” “HOLOTYPE ♂; Derelomus ; crypticus ; Haran 2025”; NHMUK.

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Paratype

REPUBLIC OF SOUTH AFRICA – Western Cape Province • 1 ♀; Pringle Bay; 34°21′00.0″ S, 18°49′48.0″ E; 28 Nov. 2019; J. Haran coll.; on male inflorescence of Phoenix reclinata ; JHAR03078- 03 ; CBGP

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Description ( ♂)

MEASUREMENTS. Body length 2.0 mm.

COLOR. Body integument pale brown, head, club, the median line of pronotum slightly darker; pattern on elytra forming elongated dark spot beyond middle of length of interstriae 4, slightly extending on interstriae 3 and 5; dorsum with minute recumbent whitish setae, glabrous in appearance.

HEAD. Rostrum as long as pronotum in lateral view, strongly and regularly downcurved, almost forming a quarter circle; in dorsal view about 3.5 × as long as wide, integument densely punctate, forming 5 longitudinal carinae; antennae inserted at apical ¼ of length in lateral view; head capsule densely punctate in dorsal view, forehead flat; eyes convex, exceeding lateral curve of head capsule in dorsal view; antennal funicle with first segment 1.5 × as long as wide, slightly longer than segments 2–3 together, 3–7 transverse.

PRONOTUM. Wider than long (W: L ratio: 1.43), widest in basal ⅔ of length, slightly narrower there than elytra at humeral angles (0.95 ×), side subparallel in basal ⅔, converging apicad in apical ⅓, forming blunt tooth beyond middle of length; apical constriction distinct, shallow, less deep than width of scape in middle of length; integument with punctures rounded, space between punctures rough, shiny, micropunctate, generally wider or narrower than diameter of punctures in middle, narrower laterally.

METATHORAX. Metanepisterna with recumbent white setae, non-contiguous.

ELYTRA. Longer than wide (W: L ratio: 0.76); sides a little convex, widest near middle of length; humeri distinct; apex rounded and jointed at level of suture; striae with punctures about ½ to ⅓ as wide as width of interstriae; interstriae slightly convex; scutellar shield rounded, a little darker than elytra, coated with small recumbent scales not concealing integument.

ABDOMEN. Underside uniformly pale brown, with minute recumbent whitish setae, not contiguous. Stridulatory plate with lines of 6–7 granules about ¾ as long as median line from base, space between granules 2–3× as wide as diameter of a granule. Central sclerotized area isodiametric, rounded at base.

LEGS. Profemora moderately thickened near middle of length; protibiae with external margin straight, internal bisinuate, setae on apical half of internal margin recumbent, shorter than length of claws; claws simple.

Sexual dimorphism

The female can be distinguished from males by the rostrum which slightly more downcurved basally in lateral view and by the antennae inserted at the apical ⅓ of the length (¼ in the male).

Life history

This species was collected on male inflorescences of Phoenix reclinata , which probably constitutes the substrate for the larvae. Adults were collected in May and November.

Distribution

In our current knowledge only known from Kenya, and the Western Cape Province of the Republic of South Africa. The population from Western Cape Province is likely an introduction since no palm is indigenous to this area.

Remarks

This species is known from very few specimens, it is seemingly rare compared to the other species found on male inflorescences of Phoenix reclinata . The elytral pattern and measurements are probably more variable than those provided in the description. The male from Kenya and the female from the Republic of South Africa are quite divergent regarding the shape of their rostrum, beyond what is expected for sexual dimorphism. Populations from these two areas are probably morphologically slightly divergent, similarly to what is observed in other species showing such distribution patterns. The penis and stridulatory plate of the only male available was unfortunately damaged during dissection and could not be used for the description.