Sanaungulus electrum, Fanti & Müller, 2022

Fanti, Fabrizio & Müller, Patrick, 2022, Fossil Cantharidae from the Cretaceous Burmese (Kachin) amber of the Patrick Müller collection, and taxonomic information, Baltic Journal of Coleopterology 22 (2), pp. 331-380 : 347-349

Sanaungulus electrum sp. nov.

( Fig. 9 )

Holotype. Male, adult specimen in a Burmese (Kachin) amber piece: Catalog number SNHM­6005 in the Staatliches Naturhistorisches Museum Braunschweig (ex Müller’s collection number: BUB4325 ).

Type locality. Myanmar: Kachin state, Myitkyina District, Hukawng Valley.

Type horizon. Lowermost Cenomanian (98.79 ± 0.62 Ma), mid­Cretaceous.

Differential diagnosis. The new species is easily distinguishable by the pronotal shape, with the sides concave at the center and with an expansion/tooth near the first apical third. These features are not present in other species of the genus Sanaungulus .

Description. Adult, winged, slender. Male, defined on the shape of the last tergite that is very elongated, and on the basis of the rounded last sternite. Body length about 2.9–3.1 mm (head is folded). Entirely brown.

Head elongated, strongly constricted (triangular­shaped) behind the eyes, fitted with rugosity and punctuation.Eyes prominent, large, roundish, inserted in the upper and dorsolateral part of the head. Mandibles elongated, robust, falciform. Antennae 11­ segmented, filiform, slender, very short and slightly surpassing the humeral zone of the elytra; scape club­shaped; antennomere II very short, globular; antennomeres III–V, thin, very long, over 2 times longer than second; antennomeres VI–X subequal in length, about 2.0 times shorter than previous ones; antennomere XI filiform, slightly longer than previous ones, rounded at apex; all the antennomeres with short pubescence. Pronotum subquadrate, slightly transverse, anterior margin straight and not bordered, posterior margin rather straight, corners obtuse, sides concave at the center and slightly expanded posteriorly and with an expansion/ tooth near the first apical third, pronotum disc smooth. Scutellum triangular­shaped. Elytra short which reveals various abdominal segments, wider than pronotum, at humery enlarged and slightly dehiscent posteriorly, rounded apexes, surface smooth without rugosity and only sligthly pubescent. Metathoracic wings transparent, long, surpassing the elytra and reaching the last abdominal segments. Sternum elongated with posterior margin irregular with an expansion at the center that is very small and forked apically, sternites wide and transverse equipped with short setae; penultimate tergite with a long and thin lobe at sides that is curved; last tergite very elongated, initially wide and flat, deeply folded apically, with the apical margin forked and globular at sides; last sternite smaller than last tergite and rounded. Legs thin, relatively short, pubescent; coxae massive, large; trochanters short, globular with rounded apex; femora nearly straight, more robust than tibiae, cylindrical; tibiae cylindrical, thin, without spurs near the apex, metatibiae very longer than metafemora. Tarsal formula 5­ 5­ 5; first tarsomere long, second tarsomere similar in size to previous one; third tarsomere short and triangular­shaped; fourth strongly bilobed and very long; fifth tarsomere elongated, thin, slightly flat and curved; claws simple, apparently without denticle at the base.

Etymology. Derived from the Latin noun “Á lectrum ” = yellow amber, succinite. Specific epithet is to be treated as noun in apposition.

Syninclusions. Air bubbles, detritus.

Remarks. Piece of clear, golden amber that measures 12x6x 2 mm. The inclusion lacks four legs and there is only one antenna that is completely detached from the body. Furthermore, the head (and its frons) in the ventral part is covered by an emulsion like white­cotton.

Figures

Fig. 9. Sanaungulus electrum sp. nov. in Burmese amber. A: Holotype, dorsal view; B: Holotype, ventral view.