Vorstadt ambermuseum Manukyan, 2023

Manukyan, A. R., 2023, New data on the subfamily Hybrizoninae (Hymenoptera: Ichneumonidae) in Baltic Amber, Russian Entomological Journal 32 (4), pp. 403-409 : 406-408

Vorstadt ambermuseum Manukyan sp.n.

Figs 1–9 .

MATERIAL. Holotype, female, KAM no. ВХ 37/23.1, Baltic amber, Late Eocene of the Baltic region. No syninclusions.

ETYMOLOGY. The species named after Kaliningrad Amber Museum which holds a significant collection of Hymenoptera inclusions in Baltic amber.

DIAGNOSIS. Vorstadt ambermuseum sp.n. differs from V. groehni by the presence of vein r-m (lost in V. groehni because RS and M are fused), weakly reclival vein 1cu-a (nervulus; antefurcal in V. groehni), as well as by the smooth (polished) sculpture of the body (reticulate in V. groehni).

DESCRIPTION. Female ( Figs 1–3 ). Head distinctly transverse, slightly narrowed posteriorly. Face narrowed downwards, distinctly convex in the middle. Clypeus small, convex and strongly protruding forwards, anterior margin flat, without notch in the middle. Occipital carina obliterated. Eyes large, without notch at level of antennae. Stemmaticum considerably elevated above head surface. Distance from the hind ocelli to eyes is equal to the diameter of the ocelli. Scapus and pedicel short, subspherical in shape; length of scapus almost equal to width, length of pedicel about 1.5 times width and 1.8 times length of scapus. Flagellum with 11 flagellomeres ( Figs 4–5 ), densely pubescent, each flagellomere with medial constriction resembling intersegmental articulation; multiporous plate sensilla present on all flagellomeres, well expressed, stretching mostly for the whole length of flagellomere, less often ceasing at constriction.

Mesonotum more or less quadrangular ( Fig. 6 ), with uniformly convex surface; situated in side view distinctly above the level of scutellum; notauli absent. Mesopleurae slightly compressed laterally, not punctured; epicnemial (prepectal) carina complete, sternauli absent; postpectal carina complete. Scutellum comparatively large, convex, bordered by carinae up to apex.

In the forewing, veins 2Rs+M and r-rs not fused on external margin of discoidal cell, vein r-m present. Vein 4Rs 5.2 times as long as r-rs. Vein 1cu-a (nervulus) interstitial and slightly reclival. Hind legs longer and distinctly thicker than fore and middle ones.

Metasoma with T1–3 elongated, T3 longer than the following ones, which are distinctly transverse. Ovipositor short ( Fig. 9 ), slightly more than half the height of metasoma at apex, broad at base, gradually narrowed towards apex, without apical dorsal notch. Sheaths scale-shaped, narrow at base, widening towards apex, 0.65 times as long as ovipositor. Sheaths shifted to the apex, considerably distant from ovipositor.

Body dark brown, antennae black, anterior tibiae yellow. Body without hairs, except for fine and sparse pubescence on sides and apex of metasoma. Flagellum densely pubescent.

Approximate measurements: body 3.1, forewing 2.8, ovipositor 0.3, sheath 0.2.

base of hind coxae. T1 and basal 0.6 of T2 longitudinally striate ....................... Tobiasites striatus Kaspayan, 1988

– Occipital carina distinct. Visible number of segments of maxillary palps 3, labial palps 2; penultimate segment of maxillary palps moderately thickened at apex. Fore wings without vein 2m-cu; r-m present. In female, fore tarsi somewhat longer than middle ones. Base of 1T situated considerably higher than base of hind coxae. Sculpture of 1T and basal 0.6 of 2T roughly cellular ............................ .... Paxylommites reticulatus Kaspayan, 1988 ( Figs 10–11 ). Male. Unknown.

REMARKS. Original description [ Tolkanitz, Perkovsky, 2015] indicates presence of a medial transverse impression on the mesonotum. However, I believe this is the result of deformation of the cuticle during fossilization.

Key to genera and species of Hybrizoninae from Baltic amber

1. Flagellum 11–13-segmented (may look multisegmented if segments constricted medially). Mandibles strongly reduced, their apices without distinct teeth and not touching each other (because of strong reduction). Notauli absent ................... 2.

– Flagellum has more than 13 (i.e., 23) segments ( Figs 10–11 ). Mandibles bidentate, not reduced, their apices touching each other. Notauli present, sharp...................................... ...................... Ghilarovites tarsatorius Kasparyan, 1988

2. Flagellomeres with distinct constrictions ( Figs 4–5 ); maxillary palps long, not reduced ( Fig. 3 ) Vorstadt gen.n.....3.

– Flagellomeres without constrictions; maxillary palps reduced or complete ......................................................... 4.

3. Vein r-m absent. Occipital carina complete. Body sculpture reticulate ......... V. groehni ( Tolkanitz et Perkovsky, 2015)

– Vein r-m presents ( Fig. 2 ). Occipital carina obliterated. Body uniformly smooth (polished) ....... V. ambermuseum sp.n.

4. Occipital carina obliterated or absent. Visible number of segments of maxillary palps 2; their penultimate (also, probably first) segment strongly widened at apex; labial palps not visible, probably reduced. Forewings with 2m-cu distinct, although depigmented; r-m lost. In male, fore tarsi shorter than middle ones. Base of T1 situated a little above

Figures

Figs 1–2. Vorstadt ambermuseum sp.n., holotype, female: 1 — dorsal view; 2 — fragment of front wing. Рис. 1–2. Vorstadt ambermuseum sp.n., голотип, самка: 1 — вид сверху; 2 — фрагмент переднего крыла.

Fig. 3. Vorstadt ambermuseum sp.n., holotype, female, ventral view. Рис. 3. Vorstadt ambermuseum sp.n., голотип, самка, вид сниЗу.

Figs 4–5. Vorstadt ambermuseum sp.n., holotype, female: 4 — flagel- lomeres of left flagellum, arrows indicate constrictions; 5 — 4th to 11th flagellomere of left flagellum, arrows indicate constrictions. Рис. 4–5. Vorstadt ambermuseum sp.n., голотип, самка: 4 — левый жгутик, стрелками покаЗаны перетЯжки; 5 — 4–11-й членики левого жгутика, стрелками покаЗаны перетЯжки.

Fig. 6. Vorstadt ambermuseum sp.n., holotype, female, head and mesoscutum, dorsal view. Рис. 6. Vorstadt ambermuseum sp.n., голотип, самка, голова и среднеспинка, вид сверху.

Fig. 7–8. Vorstadt ambermuseum sp.n., holotype, female, metasoma, ventral view: 7 — first segment; 8 — second to eighth segment Рис. 7–8. Vorstadt ambermuseum sp.n., голотип, самка, метасома, вид сниЗу: 7 — первый сегмент; 8 — второй–восьмой сегменты.

Fig. 9. Vorstadt ambermuseum sp.n., holotype, female, ovipositor and sheaths. Рис. 9. Vorstadt ambermuseum sp.n., голотип, самка, Яйцеклад и ножны.

Fig. 10 –11. Ghilarovites tarsatorius, holotype, female: 10 — left lateral view; 11 — apical flagellomeres. Рис. 10 –11. Ghilarovites tarsatorius, голотип, самка: 10 — вид слева; 11 — апикальные членики жгутика.