Agromyza nigrescens Hendel, 1920

Agromyza nigrescens: mine on Geranium pusillum

Geranium pusillum, Amstelveen, Schinkelbos

Agromyza nigrescens: mine

larva and frass

Agromyza nigrescens: mine on Geranium rotundifolium

young mine

Agromyza nigrescens: mine on Geranium robertianum

Geranium robertianum, Blitterswijck; © Wouter Bosgra

Agromyza nigrescens: mine on Geranium rotundifolium

Geranium rotundifolium, Spain, Pyrenees, Esterri d’Anneu; © Paul van Wielink

Agromyza nigrescens: mine

detail

Agromyza nigrescens mine

strongly different mine on Geranium columbinum, Belgium, prov. Namur, Sosoye; © Jean-Yves Baugnée

mine

The mine is described by Hering (1957a) as follows: “Upper-surface mine. The start is corridor-like and generally follows the leaf margin. Further on the mine widens considerably, forms a secondary blotch and gets irregular sides that are deeply eaten out. Primary and secondary feeding lines clearly visible. Frass mostly in large clumps. Pupation outside the mine. The mine only rarely occurs inGeranium robertianum; the frass then is fine-grained and the mines are smaller.”

The Dutch material differs considerably from both of these types, in particular because much of the frass is in long threads. Hering didn’t think it impossible the the miners of Geranium robertianum and the other Geranium species might be different species; in this line the Dutch material might form a third species. But it also is possible to suppose an unusually strong effect of the hostplant species upon the mine and the frass pattern.

hostplants

Geraniaceae, oligophagous

Erodium moschatum; Geranium columbinum, dissectum, molle, nodosum, palustre, phaeum, pratense, purpureum, pusillum, robertianum, rotundifolium, sanguineum, sylvaticum.

phenology

Larvae in summer (Robbins, 1991a). The larvae of the Dutch material were collected in the first half of September.

BENELUX

BE recorded (prov. Namur, Jean-Yves Baugnée).

NE recorded (Ellis, 2007: Amstelveen).

LUX not recorded (Fauna Europaea (2007).

distribution within Europe

Europe west of the line Finland – Poland – Serbia, but not (yet?) known from Ireland (Fauna Europaea (2007).

larve

puparium

synonyms

Agromyza microchaeta Hendel, 1920, A. heringi de Meijere, 1925, A. oycoviensis Beiger, 1960.

notes

While Hering (1957a( writes that the species is rare on G. robertianum, Robbins (1991a) states that in the UK robertianum is the only hostplant. This matches with Hering’s hunch that nigrescens may be a mix of two species.

references

Beiger (1960a, 1970a, 1972e), Buhr (1930a, 1932a, 1941a,b, 1964a), Černý (2004a, 2011A), Černý & Merz (2006a, 2007a), Černý & Vála (1999a), Ci̇velek, Çikman & Dursun (2008a), Gil Ortiz (2009a), Hartig (1939a), Hering (1927a, 1932e, 1955b, 1957a, 1967a), Huber (1969a), Maček (1999a), Masetti, Lanzoni, Burgio & Süss (2004a), de Meijere (1925a), Michalska (1970a), Ostrauskas, Pakalniškis & Taluntyte (2003a), Pakalniškis (1993a), Papp & Černý (2015a), Robbins (1991a), Rydén (1956a), Skala (1951a), Skala & Zavřel (1945a), Sønderup (1949a), Spencer (1953a, 1957f, 1972a,b, 1973c, 1976a), Starý (1930a), Surányi (1942a), von Tschirnhaus (1999a), Withers (2007a), Zlobin (1986b).

28/04/2017

pub 28.iv.2017 · mod 25.vii.2017