Archearadus elongatus, Heiss, 2016

Heiss, Ernst, 2016, New genera and species of Aradidae in Cretaceous Burmese Amber (Hemiptera: Heteroptera), Linzer biologische Beiträge 48 (1), pp. 419-429 : 427-428

Archearadus elongatus nov.sp. ( Figs 9-10 , photo 4)

H o l o t y p e: Brachypterous male in a piece of Burmese amber from " Kachin State " in Myanmar ( Burma) embedded in epoxyd resin (8x10x 4mm), legs and antennae complete. It is designated as holotype and labeled accordingly.

D i a g n o s i s: Differs from the male of Archearadus burmensis HEISS & GRIMALDI 2001, the type species and only taxon of this fossil genus, by larger size, brachypterous hemelytra, shorter antennae and distinctly more elongate and slender abdomen.

D e s c r i p t i o n: Brachypterous male, body surface flat with dense fine granulation; colouration stramineous; apices of antennal segments II and III brown.

H e a d: Longer than width across eyes (37/28.5); clypeus long and slender dorsally keeled, reaching about ¾ of antennal segment II; antenniferous lobes blunt, reaching ½ of antennal segment I; antennae 1.61x as long as width of head, segment I thickest and shortest, II and III thinner and longer tapering toward base, III longest, IV fusiform; length of antennal segments I/II/III/IV = 6/13/17/10; eyes laterally produced; postocular lobes roundly converging posteriorly; vertex with two rows of larger tubercles, depressed laterally; rostrum arising from an open atrium, shorter than head.

P r o n o t u m: Wider than long (41/25), lateral margins dentate, anterolateral angles acute, paranota distinct; disk with 2 straight median and 2 weakly developed sublateral carinae; posterior margin slightly concave.

S c u t e l l u m: 1.6x as long as wide (32/20), lateral margins carinate, apex narrowly rounded; disk with a median carina on anterior half.

H e m e l y t r a: Corium about as long as scutellum, lateral margins slightly reflexed, veins of disk indistinct; posterior margin rounded with a vestige of membrane.

A b d o m e n: Elongate oval, about 1.36x as long as wide across tergite V; lateral margins of deltg II-VII each with two lamellate expansions, the anterior one bilobate, the posterior one larger directed posterolaterally and rounded; mtg III-V medially roundly produced posteriorly, dorsal scent gland scars visible; ptg VIII wide, posterolaterally expanded and bilobate; pygophore dorsally exposed, a pair of hook like parameres is recognizeable.

V e n t e r: Partly obscured by impurities; position of apodemal impressions and spiracles not discernible; pit-like metapleural scent gland discernible on the right side between meso- and metacoxae.

L e g s: Long and slender, unarmed; tarsi 2-segmented, claws with pulvilli.

M e a s u r e m e n t s: Length 4.45mm; length of antennae 1.15mm, width of abdomen 1.75mm; width of ptg VIII 0.80mm.

E t y m o l o g y: This epithet refers to the elongate habitus of this taxon.

D i s c u s s i o n: Archearadus elongatus nov.sp. shares the essential characters of this genus (very long clypeus, rostrum arising far from apex, abdominal tergites separated and not fused to tergal plate, metapleural scent gland developed, claws with pulvilli) based on a single male: Archearadus burmensis HEISS & GRIMALDI, 2001. Later, a female was tentatively assigned to A. burmensis, although lacking the lateral expansions of deltg II-VII ( HEISS & GRIMALDI 2002).

Comparison of both males show, that the holotype of A. burmensis is of smaller size than A. elongatus nov.sp. (3.85/ 4.45mm), antennae are longer (1.68 / 1.61x as long as width of head), abdomen is much wider, ratio length of dorsally visible abdomen / width across tergite V= 1.12 (1.36 in A. elongatus ) and posterior margins of mtg II-V are not roundly produced posteriorly. The different outline of head results from an obvious deformation during fossilization process in A. burmensis.

Figures

Figs 9-12: Reconstruction of described taxa. 9-10: Archearadus elongatus nov.sp.: (9) habitus; (10) left antenna; 11-12: Aradoleptus birmanus nov.gen., nov.sp.; (11) habitus; (12) right antenna. Scale = 1mm.