Madelinia gedanoposita, Alekseev & Pankowski, 2020

Alekseev, Vitalii I. & Pankowski, Maximilian G., 2020, The first new genus of the tribe Hypulini Seidlitz (Coleoptera: Melandryidae) described from late Eocene Baltic amber, Zootaxa 4869 (2), pp. 281-289 : 283-286

Madelinia gedanoposita sp. nov.

( Figs. 1–3 )

Material examined. Holotype: No. 6692 [ MAIG], adult, sex unknown. Complete beetle inclusion in a transparent, yellow piece of amber with dimensions 16×7× 5 mm (weight 0.6 g) without any further fixation. The complete beetle with a partially exposed apex of its metathoracic wing is well preserved, but its forebody is not perfectly visible: Parts of the head and thorax on the ventral side are covered by a milky or opaque amber layer. Organic syninclusions are represented by stellate fagacean trichomes.

Type strata. Baltic amber from Eocene amber-bearing Blaue Erde deposits (mostly Bartonian age, as interpreted for extinct Central European resin-producing forests according to Bukejs et al. 2019).

Type locality. “Primorskoe” mine, Yantarny settlement (formerly Palmnicken), Sambian (Samland) Peninsula, Kaliningrad Region, Russia .

Diagnosis. As stated above, for the new genus.

Description. Body elongated, slightly convex dorsally; dark, unicolorous. Dorsal surface evenly punctured and covered with fine, decumbent, conspicuous pubescence.

Measurements: Body length approximately 5.8 mm (measured laterally, head obliquely directed as preserved), maximum body width 1.8 mm (elytra postmedially); head length about 0.6 mm; pronotal length about 1.0 mm, maximum pronotal width 1.2 mm; elytral length 4.5 mm.

Head. Compound eyes weakly convex, without intrafacetal setae; ommatidial facets distinct and fine (as large as punctures on anterior part of pronotum). Terminal maxillary palpomere cultriform, 2.5 times as long as penultimate palpomere. Antennae 11-segmented, filiform, reaching posteriorly to humeri, with short pubescence. Antennomeres 3–10 conically elongated, all almost uniform in size, about 3 times as long as wide; pedicel cylindrical, about 2 times as long as wide; scape and antennomere 11 slightly wider than other antennomeres; scape rounded; antennomere 11 ovoid, pointed apically, about 1.5 times as long as antennomere 10.

Thorax. Pronotum transverse, 1.2 times as wide as long, widest at middle. Pronotal base narrower than elytra at humeri. Anterior margin of pronotum slightly rounded; posterior margin bisinuate; lateral pronotal margins gradually narrowed toward the anterior from the middle. Lateral pronotal carina present, discernible in lateral view in one-third of pronotal length basally. Anterior angles rounded; posterior angles pronounced, pointed, acute. Pronotal disc slightly convex, uneven, with pair of shallow symmetrical depressions at middle. Basal impressions distinct, comparatively deep, triangular, reaching one-fourth of pronotal length. Pronotum densely punctate, distance between punctures equal to 0.5 times diameter of one puncture. Punctures with decumbent fine long hairs directed toward the posterior, as long as 2.0–3.0 times diameter of one puncture.

Elytra elongate, widest behind the middle, with distinct humeri and separately rounded elytral apices. Elytral disc slightly convex; dorsal surface evenly and irregularly punctate and pubescent. Pubescence decumbent, long; distance among punctures equal to 0.5–2.0 times diameter of one puncture (denser at the base, sparser posteriad). Hind wings present. Scutellar shield transverse, 1.6 times as wide as long, oval, matte. Elytral epipleura narrow, widest basally and then gradually narrowed toward the posterior.

Legs slender. Procoxae contiguous. Meso- and metacoxae narrowly separated. Femora weakly flattened. Tibiae straight, subequal in length to femora, finely punctate and setose, with two short spurs of equal length on the inner angle apically. Metatibial spurs about 0.5 times as long as tibial width at apex, slightly serrate at inner side. Tarsi 5-5-4. Penultimate tarsomere of all legs lobed. Protarsomere 2–4 widened, transverse. Tarsal claws simple, symmetrical. Ratio of metatarsomere lengths 4.0: 1.0: 0.7: 1.0.

Abdomen with five visible abdominal ventrites. All ventrites finely punctate and shortly pubescent. Ratio of lengths of ventrites 1–5 2.5: 2.5: 2.0: 1.0: 1.0 (medially).

Etymology. The specific epithet gedanoposita is a compound Latin adjective formed from “Gedanum” (the Latin name of Gdańsk) and “positus, -a” (placed, deposited), meaning “deposited in Gdańsk.”

Figures

FIGURES 1–2. Madelinia gedanoposita gen. et sp. nov., holotype, No MAIG 6692, habitus: 1) dorsal view; 2) right lateral view. Scale bars represent 1.0 mm.

FIGURE 3. Reconstruction of Madelinia gedanoposita gen. et sp. nov. from Baltic amber: habitus, dorsal view. Body length approximately 5.8 mm.