Poinarelektronmiles cuaroni, Bramanti & Fanti, 2022

Bramanti, Andrea & Fanti, Fabrizio, 2022, A new taxon of the soldier beetles’ genus † Poinarelektronmiles from Burmese amber (Coleoptera: Cantharidae), Fragmenta entomologica 54 (2), pp. 201-206 : 203-204

Poinarelektronmiles cuaroni sp. n.

Type material. Holotype. Sex undefined, adult specimen in a Burmese ( Kachin ) amber piece, with the Catalog number 121 in the Andrea Bramanti collection ( Pietrasanta , Lucca , Italy), and later donated to the Natural History Museum of University of Pisa, Italy. Type locality: Myanmar, Kachin state, Myitkyina District , Hukawng Valley . Type horizon: Lowermost Cenomanian (98.79 ± 0.62 Mya ), mid-Cretaceous.

Differential diagnosis. Poinarelektronmiles cuaroni sp. nov., differs from the only other known species of the genus: Poinarelektronmiles ellenbergeri Fanti & Damgaard, 2020 in having pectinate antennae with the antennomeres V-IX, instead of antennomeres III-IX, equipped with a long antennal process ( Fanti & Damgaard 2020). Furthermore, in the new species here described the last antennomere is securiform and much more robust ( Fig. 2).

Etymology. Named in honor of the movie director, screenwriter, and film producer Alfonso Cuarón Orozco (Mexico City: November 28, 1961), a dear friend of the first author.

Description. Adult, alate, slender. Sex undefined. Entirely testaceous-brown. Head transverse, rounded behind the eyes, slightly covered by the pronotum, surface pubescent with shallow and rare punctation. Eyes prominent, convex, rounded, inserted laterally to the head. Mandibles not visible. Maxillary palps 4-segmented, with the last palpomere short and slightly securiform. Labial palps 3-seg- mented with the last palpomere securiform. Antennae 11-segmented, pectinate, inserted in the upper part of the head and far from the eyes, slightly surpassing half of abdomen and metathoracic legs; scape slightly club-shaped, robust, elongated; antennomere II very short, about 3.5 times shorter than scape; antennomere III longer and slightly narrower than previous one, enlarged apically; antennomere IV robust, about 1.6 times longer than third; antennomere V extremely elongated, the longest, narrower than previous one, at apex with an extremely long antennal process which is rounded apically and slightly longer than the subsequent antennomere; antennomere VI extremely long, narrow, slightly shorter than previous one, with at apex an antennal process similar to the previous one; antennomere VII shorter than previous one, narrow, enlarged apically, with an apical process sturdier than previous ones; antennomeres VIII-IX subequal in length, with an apical process which is robust, longer than antennomere and squared apically; antennomere X shorter than previous one, without antennal process; antennomere XI short, very robust, rounded apically, deeply securiform; all antennomeres with short setae ( Fig. 1). Pronotum slightly transverse, slightly narrower than head, enlarged at posterior corners, anterior margin undulate and finely bordered, sides rounded and bordered, posterior margin almost straight and bordered, surface completely flat with pubescence (just perceptible). Scutellum wide at base and pointed posteriorly with rounded apex. Elytra elongated, surpassing the last abdominal segment, at humeri wider than pronotum and narrower posteriorly, parallel-sided, not dehiscent, rounded at apex, surface presenting shallow or slightly in relief punctation gathered in confused striae ( Fig. 1). Metathoracic wings covered by elytra and not visible. Sternum subquadrate. Sternites transverse and wide, last tergite rounded and wide. Legs elongated and equipped with pubescence; coxae short; trochanters elongated, rounded apically; femora straight, cylindrical and slightly flat in the center, sturdier than tibiae; tibiae thin, elongated, cylindrical, longer than femora. Tarsal formula 5-5-5; first tarsomere elongated, thin; second tarsomere elongated, thin, shorter than first; third tarsomere trian- gular-elongated, more than 2 times shorter than second; fourth tarsomere strongly bilobed with lobes extremely thin and long; fifth tarsomere very elongated, straight, very thin and slightly enlarged apically; claws simple, apparently with a very small tooth near the base ( Figs. 1–2). Measurements (mm). Body length: 3.4; elytra: length 2.5, width 0.8 at humeri; pronotum: length 0.5, width 0.6.

Syninclusions. Elytron, botanical remains and air bubbles.

Systematic placement. The head rounded behind the eyes, pronotum smooth without depressions or thickening, slender and long elytra covering and very slightly surpass the abdomen, and the pectinate antennae with long antennal processes, make this new species belonging to the genus Poinarelektronmiles Fanti & Damgaard, 2020 . The other genera of Cretaceous Burmese amber have elytra more abbreviated or pronotum with depressions ( Fanti & Damgaard 2020; Zhao et al. 2022). Other genera: Nothotytthonyx and Archaeomalthodes have the last maxillary palpomere globular and pointed, a character which makes them belong to a different subfamily.

Remarks. Piece of amber 38 mm long, 22 mm wide and 8 mm high. The inclusion is complete, except for the left antenna preserved up to the middle of the fifth antennomere, the legs are partially folded and the ventral view is scarcely evident due to the emulsion and shape of the amber.