Aprionus ymiri Jaschhof & Jaschhof 2017, sp. nov.

Aprionus ymiri sp. nov.

urn:lsid:zoobank.org:act: 1DF5CB60-323F-4323-8193-E7A68862BDCB

Fig. 17

Diagnosis

The male genitalic structures of Aprionus ymiri sp. nov. are as simple as characteristic of this species. The gonostylus is composed of two portions of the same size, a slightly convex portion basally and a flat portion apically; the gonostylar apex is narrowly rounded and provided with ordinary setae and setulae, no teeth or bristles (↓, Fig. 17B). The tegmen, which is tapered from the midlength to the narrowly rounded apex, is provided with 2 pairs of small, weakly contoured fingers, which do not intersect medially due to their rearward orientation (↓, Fig. 17A). A ventral plate is not apparent in this species.

Etymology

Ymir is the ancestor of all jotunn, a mythological race commonly glossed as the giants.

Material examined

Holotype

SWEDEN: ♂, Öland, Borgholm, Skepparsäng Nature Reserve, 57.31° N, 17.04° E, dry pine forest, Malaise trap, M. and C. Jaschhof leg., 11 Jun.–21 Jul. 2015 (NHRS, no. CEC288).

Paratype

FINLAND: ♂, Karelia borealis, Lieksa, Patvinsuo NP, 63.08° N, 30.37° E, mature spruce forest with birch and aspen trees, MT, MCJ leg., 12 Jun.–7 Jul. 2004 (DEI, no. CEC 289).

Differential diagnosis

Aprionus ymiri sp. nov. lacks characters that, seen individually, would catch the observer’s attention, but the combination of characters as described above is species-specific. To avoid misidentification, this rarely found species should be compared with both Aprionus dispar Mamaev, 1963 and A. pseudispar Jaschhof, 1997 (see Jaschhof 1998: figs 151, 155), two much more common species.

Other characters

Body size 1.1 mm.

HEAD. Postfrons setose. Eye bridge 2–3 ommatidia long dorsally. Postocular bristles: 10 in holotype, 7 in paratype. Neck of fourth flagellomere shorter than node, thick, simply hair-shaped translucent sensilla (Fig. 17C). Palpus short, 3-segmented in holotype, 2-segmented (but equally long) in paratype, basal segment somewhat swollen.

WING. ApicR 1 2.5–3.0 times as long as Rs.

LEGS. Claws sickle-shaped, toothless. Empodia rudimentary.

TERMINALIA (Fig. 17A). Ninth tergite subrectangular, anterior margin fully sclerotized, concave medially. Gonocoxites slightly pointed ventroposteriorly, dorsal bridge small, subtriangular, extends far beyond ventroanterior gonocoxal margin.

Distribution and phenology

Sweden (Öland), Finland (Karelia borealis). Adults were collected in June–July in various types of forest.

Aprionus incertae sedis

This category gathers Aprionus, 12 described in the past and three described here, that cannot be classified in any of the species groups recognized so far (Jaschhof 1998; Jaschhof & Jaschhof 2009). We think that the number of ‘unplaceables’ will not increase with more species being found and described in the future; rather we expect that the affinities of these species to other Aprionus will be illuminated and the intrageneric structure of Aprionus improved with ongoing study (see the differential diagnoses of Aprionus bestlae sp. nov. and A. borri sp. nov.).