Malthodes (Libertimalthodes) betseyae, PANKOWSKI & Fanti, 2023

PANKOWSKI, MAXIMILIAN G. & Fanti, FABRIZIO FANTI, 2023, Six new species of fossil soldier beetles (Coleoptera: Cantharidae) from Eocene Baltic amber, Palaeoentomology 6 (3), pp. 300-312 : 307-309

Malthodes (Libertimalthodes) betseyae sp. nov.

( Fig. 6 )

Holotype. Male , inclusion in Baltic amber, housed at the Smithsonian National Museum of Natural History, USNM PAL 787827 .

Syninclusions: Air bubbles (some quite large), botanical fragments and detritus.

Etymology. Species named after Betsey Kim, great aunt of the first author who spent her life teaching and inspiring hundreds of schoolchildren in Tallahassee, Florida.

Diagnosis. The globular and distally pointed last maxillary palpomere, the elongate and smooth elytra, the head rounded behind the eyes, the unmodified last abdominal segments, and the robust and large aedeagus place this species in the genus Malthodes and its subgenus Libertimalthodes ( Brancucci, 1980; Fanti, 2019b).

Malthodes (Libertimalthodes) betseyae sp. nov. is similar to M. (L.) elytratus Kupryjanowicz & Fanti, 2019, but the new species differs in its slightly longer antennae, its pronotum transverse with sides straight, and by its last sternite not rounded at the sides and with a deeper central apical concavity ( Kupryjanowicz & Fanti, 2019).

Locality and horizon. Amber mine in the Yantarny settlement, Sambian Peninsula, Kaliningrad region, Russia. Middle Eocene (Lutetian) (47.8–41.2 Ma) to late Eocene (Priabonian) (37.8–33.9 Ma).

Description. Male, defined on the basis of a small part of visible aedeagus. Body length: about 4.0– 4.1 mm. Body entirely dark brown without yellow spots on elytra.

Head exposed, wide, rounded, slightly granulous with shallow punctation and several setae. Eyes large, rounded, located in upper lateral part of head. Mandibles not well visible. Maxillary palps 4-segmented, with the last palpomere globular and distally pointed. Labial palps 3-segmented with the last palpomere globular and pointed. Antennae filiform, 11-segmented, relatively long, slightly surpassing half the length of elytra; antennomere I club-shaped, robust, enlarged apically; antennomere II rather long, about 2.0–2.1 times shorter than scape; antennomere III slightly longer than second; antennomere IV slightly longer than third; antennomeres V–VI subequal, slightly longer and slightly thinner than previous one; antennomeres VII–X filiform, subequal, slightly shorter than previous ones; antennomere XI elongate, filiform, apically rounded; all antennomeres with several setae. Pronotum transverse, wider than head, surface flat, equipped with several short setae and with small and shallow punctation, anterior margin slightly rounded, posterior margin straight and bordered, sides straight, corners strongly rounded. Scutellum triangularshaped, rounded at apex. Elytra elongate, wider than pronotum, parallel sided, apex rounded, surface slightly granulous and equipped with scattered and long setae and without punctation. Posterior wings about as long as elytra, completely covered by elytra. Legs relatively short, rather robust, pubescent; coxae wide and rounded; trochanters elongate, rounded at apex; femora robust, subcylindrical, slightly curved; tibiae shorter than femora, cylindrical, thin, with spur at apex. Tarsomeres robust; tarsomere I elongate; tarsomere II about 1.8 times shorter than first; tarsomere III shorter than second, triangular shaped; tarsomere IV strongly bilobed with lobes curved; tarsomere V elongate and flat; claws simple without lobes or teeth. Metasternum with short pubescence and slightly granulous. Abdominal segments transverse, wide, with sparse and long setae, slightly granulous; ultimate sternite wide, robust, elongate, with sides not rounded and rather straight, apical margin with a small and deep concavity in the middle; last tergite barely visible, small. Aedeagus slightly extruded, large, wide, parameres– laterophyses elongate, enlarged and squared apically. Female unknown.

Remarks. The yellow amber piece, rounded and flat, measures approximately 12 × 11 mm. The inclusion is complete with the head and pronotum barely visible in ventral views, due to the presence of large air bubbles. The surface of the amber has numerous fractures.

Figures

FIGURE 6. Malthodes (Libertimalthodes) betseyae sp. nov. in Baltic amber. Holotype (USNM PAL 787827). A, Dorsal view. B, Ventral view. Scale bars = 0.5 mm.