Omophron (Omophron) pallidum, Anichtchenko & Valainis, 2023

Anichtchenko, Alexander & Valainis, Uldis, 2023, Revision of the subgenus Omophron (s. str.) Latreille, 1802 (Coleoptera: Carabidae Omophron) of the Afrotropical region, Zootaxa 5284 (2), pp. 201-246 : 207

Omophron (Omophron) pallidum sp. n.

Type material: MALI: Holotype, male — „Mali, Kara, Flood-plain, 30.11.68, R.A. Farrow, OICMA”, „ light trap ” [13.893386, -5.538204] ( BMNH) . Paratypes: idem, but 29.6.69 (4 ♁, 8 ♀, BMNH) ; 2 ♁, 1 ♀ —„Mali Republic, Macina, Tilembeya , Niger Bank, OICMA, 5.6.65” [13.959143, -5.348306] ( BMNH) . 1♀ —„Mali Republic, Macina, Tilembeya, I. Temi , 19.5.67, R.A. Farow ”, „ light trap ” [13.959143, -5.348306] ( BMNH) .

Differential diagnosis. Similar to O. distinctum , but pronotum with long rugae. Intervals of elytra on the disc and on the sides almost identically convex. Microreticulation on the sutural interval more or less isodiametric, while in O. distinctum is transversal.

Description. Body length 5.0– 5.3 mm; width 3.4–3.5 mm. Habitus ( Fig. 3 ).

Color: head, pronotum, elytra, legs and antennae pale brown. Elytral pattern brown. Mandibles brown, the apex dark brown, almost black. Ventral side excluding epipleura brown; epipleural sides of elytra and pronotum lighter.

Head flat and wrinkled, without punctuation; brown, with yellow clypeus and frons. Subocular ridge well developed, curved upwards and slightly rounded. Clypeus uniform, bisetose, with curved upwards sides. Labrum with bisinuate anterior margin, with moderately rounded sides and six setae. Antennal scape bisetose at apex, antennomeres III and IV with setae along lateral margin, V–XI covered with thin setae. Gena weakly wrinkled. HW: 1.7–1.75 mm.

Pronotum (PL: 1.28–1.33 mm, PW: 2.76–2.80 mm.) moderately convex, base bisinuate on each side, sides rounded near anterior angles and curved near base, with moderately wide border expanded toward the anterior angles. Anterior angles acute, strongly prominent forward. Pronotum with long wrinkles on the disc, shorter in length toward the sides. Median impression complete. Prosternum faintly wrinkled, proepisternum smooth, sterna faintly wrinkled laterally.

Elytra (EL: 3.19–3.25 mm, EW: 3.49–3.53 mm.) moderately convex, oval. Elytra with 15 striae. Striae well developed, distinctly punctate, punctures broad and moderately deep. Intervals on the disc almost identicaly convex as on the sides. Metasternum and mesosternum smoth; mesepisternum, metepisternum gently wrinkled, more strongly on the sides of sterna. Metacoxae unisetose.

Aedeagus ( Fig. 6 ). Median lobe small and relatively slender, ventral side slightly arcuate in basal half and straight in apical half. Apex slightly downturned in lateral view. Apical lamella moderately long, in dorsal view obtuse.

Etymology. Its specific name, pallidum , is Latin for “pale”, denoting its light coloration of body.

Distribution. Species is known only from type locality, situated in the middle fork of the Niger river in Mali (Map. 1).

“ minutum ” Species Group

Members of this group are distinguished as follows: epipleura punctate, venter densely and coarsely punctate ( Figs. 9–10 , 19–20 , 24–26 ); ventrites IV and V with transverse row of punctures and a deep transverse sulcus, ventrite VI densely and coarsely punctate; disc of pronotum with more or less visible transverse depression in anterior half; maxillary palpi slender, with preapical palpomere slightly narrower than apical palpomere, apical palpomere fusiform, apex more or less acute. There are seven species in this group and all have rarely been collected.

Figures

FIGURES 1–3. Habitus of Omophron africanum- species group, dorsal view: 1—O. (O.) africanum; 2—O. (O.) distinctum; 3—O. (O.) pallidum sp. n. (Paratype). Scale bar 5 mm.

FIGURES 4–6.Aedeagus structure. a—apex in dorsal view, b—right lateral view: 4—O. (O.) africanum; 5—O. (O.) distinctum; 6—O. (O.) pallidum sp. n. (Paratype). Scale bar 1 mm.

FIGURES 9–10. Habitus of Omophron “minutum”—species group, ventral view: 9—O. (O.) minutum (Senegal, Khayes); 10—O. (O.) riedeli (Zimbabwe, Sebakwe). Scale bar 5 mm.

FIGURES 19–20. Habitus of Omophron “minutum”—species group, ventral view: 19—O. (O.) clavareaui; 20—O. (O) secundum sp. n. (Holotype). Scale bar 5 mm.

FIGURES 24–26. Habitus of Omophron “minutum”—species group, ventral view: 24—O. (O.) muellerae sp. n.; 25—O. (O.) schuelei sp. n. (Holotype); 26—O. (O) mimeticum sp. n. (Holotype). Scale bar 5 mm.