Electroanellus Simutnik, 2023

Simutnik, Serguei A. & Perkovsky, Evgeny E., 2023, Description of a new genus and species of Encyrtidae (Hymenoptera: Chalcidoidea) from Danish amber, based on a male specimen featuring an antenna with a distinct anellus, Zootaxa 5369 (3), pp. 437-445 : 438

Electroanellus Simutnik , gen. nov.

urn:lsid:zoobank.org:act:4EF1874A-90E0-488F-8714-079053D39556

Figs 1–4

Type species. Electroanellus belokobylskiji Simutnik , sp. nov., by present designation.

Species composition. Monotypic.

Etymology. The name is a combination of “electrum” (Latin: electrum = amber) and “anellus”. The presence of an anellus between the pedicel and the first segment of the funicle is the main difference between the new genus and most extant encyrtid taxa, as well as all described fossil species. The genus name is a masculine noun.

Diagnosis. Male. Body not flattened, compact; antennae clavate, short, with distinct anellus between pedicel and F1 ( Figs 1A , 2B–D ), F1 broader than long, all funicle segments not longer than broad; flagellum not flattened; clava with distinct, differentiated sensory region (apical micropilose area); setae of pubescence of antenna shorter than diameter of apical funicular segments ( Fig. 2C ), whorls of long setae absent; pedicel long and conical; scape very long, only slightly shorter than funicle; antennal scrobes sharply margined; interantennal prominence dorsally rounded (in contrast to extant Mucrencyrtus Noyes, 1980 ) not narrowed to acute point; notaular lines absent but there are large flowing depressions on mesoscutum anteriorly ( Fig. 3A : dm); scutellum convex; marginal vein about as long as broad, 2× as broad as postmarginal vein, with small darkened area underneath; postmarginal vein very long, slightly longer than stigmal vein; mandible apparently either 3-dentate or with 2 teeth and truncation of upper tooth ( Figs 2A, B ); filum spinosum absent; covering setae of linea calva poorly developed; cerci advanced.

Female. Unknown.

Remarks. Tentative placement of Electroanellus in Tetracneminae is supported by the absence of filum spinosum of the linea calva.

The clavate antennae are present in the males of several extant genera of Encyrtinae : Bothriothorax Ratzeburg, 1844 , Copidosoma Ratzeburg, 1844 , Aschitus Mercet, 1921 , Homalotyloidea Mercet, 1921 , Aphycus Mayr, 1876 , Metaphycus Mercet, 1917 , Pseudococcobius Timberlake, 1916 , Microterys Thomson, 1875 , and some others. But the males of extant Tetracneminae , as well as of the majority of extant Encyrtinae , usually have long, filiform antennae, with a long pubescence, short scape, and hemispherical, not conical, pedicel ( Trjapitzin 1989). Anelli between the pedicel and F1 very rarely occur in extant Encyrtidae and when present can usually be seen only at high magnification (e.g., in Oriencyrtus Sugonjaev & Trjapitzin, 1974 ). Anelli are not taken into account when counting funicle segments within this family ( Trjapitzin 1989). The new genus has one distinct anellus, and it further differs from all known Eocene Encyrtidae by its relatively short and wide marginal vein that is as long as broad.

Electroanellus is considered unplaced within Tetracneminae .

Figures

FIGURE 1. Electroanellus belokobylskiji, holotype male A body, dorsolateral view (anl—anellus, cer—cercus), B body, ventrolateral view (dig—digitus, cers—cercal setae).

FIGURE 2. Electroanellus belokobylskiji, holotype male: A, B head, antennae, mandible, anterolateral view C left antenna D head, mesosoma, dorsolateral view. Scale bars: 0.1 mm (A–C); 0.2 mm (D).

FIGURE 3. Electroanellus belokobylskiji, holotype male: A body, dorsal view (dm—depression on mesoscutum) B wings. Scale bars: 0.5 mm (A); 0.1 mm (B).

FIGURE 4. Electroanellus belokobylskiji, holotype male: apex of gaster, ventral view (ab—air bubble, adg—aedeagus, cers— cercal setae, dig—digitus, phl—phallobase). Scale bar: 0.1 mm.