Holotype, ♀, length of body 1.8 mm, of fore wing 2.0 mm.

Head. Antenna 1.4 times length of fore wing and 1.6 times body (Fig. 1a), with 21 segments, setae erect and about 1.3 times as long as width of segment, length of third segment 0.8 times fourth segment (Fig. 2l), length of third, fourth and penultimate segments 5.0, 6.3 and 3.0 times their maximum width, respectively; fourth segment narrowed basally in lateral view (Fig. 2l); maxillary and labial palp with 6 and 4 segments, respectively; length of maxillary palp 1.2 times height of head; OOL:diameter of posterior ocellus:POL = 7:2:3; frons glabrous and smooth, nearly flat; length of eye in dorsal view 1.6 times temple (Fig. 2h); eyes glabrous except for a few setae; temples nearly parallel-sided behind eyes (Fig. 2h); median groove of vertex shallow; face 1.5 times wider than high medially, smooth, but medio-ventrally somewhat rugulose, with long erect upward directed setae; clypeus largely smooth, sparsely finely punctate, rather convex medially, long setose, not tuberculate laterally and ventral rim truncate (Fig. 2g); epistomal groove rather wide, laterally smooth and distinct (Fig. 2g); anterior tentorial pits medium-sized (Fig. 2g); length of malar space 0.2 times basal width of mandible; mandible medially rugulose, hardly widened subapically, its medial length 1.5 times maximum width, second tooth much longer than both lobe-shaped lateral teeth, without incision between first and second tooth, third tooth with curved carina (Fig. 1a–d); head 1.6 times as wide as mesoscutum (Fig. 2d).

Figure 1.  

Aphaereta vondelparkensis sp. n., ♀, holotype. a. habitus, lateral aspect; b. mesosoma, ventral aspect; c. mandible, full sight on middle tooth; d. id., but full sight on third tooth.

Figure 2.  

Aphaereta vondelparkensis sp. n., ♀, holotype. a. fore wing; b. hind wing; c. mesosoma, lateral aspect; d. mesosoma, dorsal aspect; e. first metasomal tergite, dorsal aspect; f. legs; g. head, anterior aspect; h. head, dorsal aspect; i. head, lateral aspect; j. hind tarsus, lateral aspect; k. antenna; l. base of antennae, lateral aspect; m. apex of antenna.

Mesosoma. Length of mesosoma 1.3 times its height; pronope absent, but posteriorly with a transverse and indistinctly crenulate groove and no antescutal depression; side of pronotum largely smooth, antero-medially and ventro-posteriorly finely crenulate (Fig. 2c), ventral area moderately convex, medium-sized and yellowish-orange; precoxal sulcus entirely impressed, but only anteriorly and medially moderately crenulate (Fig. 2c); mesosternal sulcus medium-sized and moderately crenulate (Fig. 1b); metapleuron smooth dorsally and medially, rugose ventrally; notauli absent, only anteriorly with horizontal carina (Fig. 2d); medio-posterior depression of mesoscutum absent; mesoscutum glabrous (except for a few setae), smooth, strongly shiny and with complete lateral carina; scutellar sulcus medium-sized, transverse and deep, with one long and two short crenulae; axillar depression narrow, smooth and rather shallow (Fig. 2d); scutellum slightly convex; anteriorly metanotum with short median carina and not protruding dorsally (Fig. 2c); surface of propodeum mainly smooth, without lateral protuberance, its medio-longitudinal carina distinctly lamelliform and protuberant and posteriorly with narrow triangular medial area (Fig. 2c,d).

Wings. Fore wing: 2-SR oblique; r:3-SR:SR1 = 4:20:57; r vertical and about as long as width of pterostigma, narrow (about 4 times as long as its own width), distance between base of pterostigma and base of vein r 2.6 times as long as vein r and distinctly angled with 2-SR (Fig. 2a); disco-marginal cell slender (Fig. 2a; pterostigma narrow elliptical; SR1 straight and ending nearly at apex of wing; 1-CU1:2-CU1 = 1:9; 2-SR:3-SR:r-m = 11:20:3; r-m oblique; first subdiscal cell open ventrally and apically; CU1a at level of 2-CU1; m-cu slightly converging to 1-M. Hind wing: narrow apically; no trace of cu-a and m-cu; basal cell open posteriorly and veins largely hardly or not sclerotised (Fig. 2b).

Legs. Hind coxa smooth; tarsal claws very slender (Fig. 2f and j), no distinct protuberance but widened basally; middle femur slender and parallel-sided; middle tibia moderately erect setose (Fig. 2f); fourth segment of middle tarsus 1.5 times longer than wide in dorsal view and bristly setose and bristles somewhat shorter than twice width of segment; length of femur, tibia and basitarsus of hind leg 5.4, 10.1 and 6.0 times their width, respectively; hind femur largely smooth and parallel-sided, but basally narrowed; hind tibia with erect setae, somewhat widened apically and subbasally setose; hind tarsal segments with rather short and sparsely setose ventro-apical protuberance (Fig. 2j); hind basitarsus comparatively slender and parallel-sided, apically with medium-sized acute lamella (Fig. 2j); length of hind tibial spurs 0.20 and 0.25 times hind basitarsus.

Metasoma. Length of first tergite equal to its apical width, its surface distinctly convex medially and finely rugose medially, remainder largely smooth (Fig. 2e), its dorsal carinae distinct in basal 0.9 and tergite widened behind spiracles (Fig. 2e); dorsope rather large; second tergite smooth; ovipositor straight; length of setose part of ovipositor sheath 0.37 times fore wing, equal to metasoma, 1.6 times hind femur and 1.1 times hind tibia, with very long setae, ribbon-shaped (except apically) and with a short apical spine; hypopygium medium-sized and apically subtruncate (Fig. 1a).

Colour. Black or dark brown; pedicellus of antenna brown; palpi, tegulum, coxae, trochanters, trochantelli and metasoma largely medio-ventrally (including hypopygium) pale yellowish; scapus and remainder of legs (but telotarsi infuscate) brownish-yellow; humeral plate and remainder of antenna dark brown; mandible (but margins darkened), propleuron, pronotal side ventrally and first tergite orange; pterostigma, parastigma and vein r brown; wing membrane slightly infuscate.

Variation. Length of fore wing 1.8–2.9 mm; antenna of ♀ with 21(2), 22(2), 23(3), 24(3), 25(9) or 26(6) segments; third antennal segment 0.6–0.8 times as long as fourth segment; metasoma ventrally often largely dark brown and only hypopygium yellowish; third antennal segment of ♀ usually slender (Fig. 2l), but sometimes robust, 3.8–5.0 times longer than wide; second submarginal cell of fore wing slender in small specimens (Fig. 2a) to robust in larger specimens, 2.5–2.8 times longer than its maximum width; vein 2-SR of fore wing 2.4–2.8 times as long as vein r; vein 1+2-CU1 of fore wing distinctly pigmented in nearly all specimens; propodeal areola present, narrow triangular or medium-sized to narrow parallel-sided and dorsally distinctly protruding. The only male examined is very similar to females and it has 27 antennal segments.

Named after the famous city park of Amsterdam (Vondelpark) where the holotype was collected during the Taxon Expedition in Amsterdam.

Netherlands.

Gregarious parasitoid of Sarcophagidae and Calliphoridae larvae living in decaying carcasses.