Aprionus ogawaensis, Jaschhof & Jaschhof, 2017

Jaschhof, Mathias & Jaschhof, Catrin, 2017, New species of Aprionus (Diptera, Cecidomyiidae, Micromyinae) from Sweden and other parts of the Palearctic region, European Journal of Taxonomy 378, pp. 1-38 : 7-8

Aprionus ogawaensis sp. nov.

urn:lsid:zoobank.org:act:54A17E89-DFC6-409F-A02A-114016F8C423

Fig. 3

Diagnosis

Aprionus ogawaensis sp. nov. is the only species of the angulatus group with a subanal plate, although weakly sclerotized and poorly contoured (↓, Fig. 3A ). Other peculiarities are the gonocoxal apodemes lacking medial extensions and the tegminal pillars ending in small, posteriorly directed processes (↓, Fig. 3A ).

Etymology

The species epithet refers to Ogawa, a research forest in the Abukuma Highlands of Honshu, where all specimens known of this species were collected.

Material examined

Holotype

JAPAN: ♂, Honshu, Ibaraki, Kitaibaraki, Sadanami , Ogawa Research Forest , 600 m a.s.l., plantation of sugi ( Cryptomeria japonica ) interspersed with broadleaf trees, Malaise trap, K. Maeto leg., 27 May– 11 Jun. 1996 ( KUEC, no. A7638 ).

Paratypes

JAPAN: 3 ♂♂, same locality, but mature mixed broadleaf forest, MT, MCJ leg., 11 May– 1 Jun. 1999 ( DEI, nos A 7639– A 7641).

Differential diagnosis

The gonostylar apex in Aprionus ogawaensis sp. nov. is broadened (↓, Fig. 3A ) but not to the same extent as in both A. denticulus Berest, 1986 (see Jaschhof 1998: fig. 172b) and A. marginatus Mamaev, 1963 (see Jaschhof & Jaschhof 2009: fig. 75C). All other species of the angulatus group have narrow gonostylar apices (see Jaschhof & Jaschhof 2009: fig. 75A–B, D–E).

Other characters

Body size 1.2–1.3 mm.

HEAD. Eye bridge 2–3 ommatidia long dorsally. A dense row of 10–12 postocular bristles. Neck of fourth flagellomere shorter than node; translucent sensilla thick, simply hair-shaped ( Fig. 3B ). Palpus 4-segmented.

WING. ApicR 1 2.5–3.5 times as long as Rs. CuA slightly curved, ends before wing margin.

LEGS. Claws sickle-shaped, 1–2 fine teeth (hardly visible at times). Empodia half as long as claws.

TERMINALIA. Ninth tergite short, posterior margin slightly sinuous, anterior margin irregularly sclerotized, setae limited to a poorly sclerotized area medioposteriorly ( Fig. 3C ). Gonocoxites ( Fig. 3A ): ventroapical lobes small; ventrobasal apodeme strongly sclerotized, long, slender. Gonostylus blunt-ended, 2+1 short bristles among dense setulae and microtrichia apically; dorsoapical portion larger than ventrobasal portion ( Fig. 3A ). Tegmen: lateral pillars thick, touching subapically; central opening small, without spinulae ( Fig. 3A ).

Distribution and phenology

This species is known from a single low-mountain site in central Honshu, Japan, where specimens were collected in late May to early June.

The halteratus group

Named after Aprionus halteratus (Zetterstedt, 1852) , this species-rich group includes Aprionus with entire, toothed gonostyli and mostly finger-bearing tegmina ( Jaschhof & Jaschhof 2009: 243). The group is, by all indications, unlikely monophyletic. One indication is the great variation of morphological structure found within the group, which requires dividing it into several subgroups, with some species fitting in none of these. Another indication is the fact that in a part of the included species, tegminal fingers are vestigial or absent, which means an overlap with the smirnovi group (see below). Both the halteratus and smirnovi groups are maintained merely for practical reasons. The styloideus subgroup is introduced here as a monophyletic subset of the halteratus group.

1) The insignis subgroup of the halteratus group

In the species classified here, tegmina are lengthwise subdivided into a pair of cavities that contain the finger-like processes; the medial gonocoxal bridges have pointed projections ventromedially; and the subanal plate, which is weakly contoured, has only a few dark markings marginally (see Jaschhof & Jaschhof 2009: 246). This subgroup is named after Aprionus insignis Mamaev, 1963 .

Figures

Fig. 3. Aprionus ogawaensis sp. nov., holotype, ♂. A. Genitalia, ventral. B. Fourth flagellomere, lateral. C. Ninth tergite, dorsal. Scale lines: 0.05 mm. Arrows indicate diagnostic characters.