Jordanita tenuicornis (Zeller, 1847)

Host plants:
The larvae feed on thistles and Centaurea species, e.g. on Centaurea solsistalis.

Habitat:
Jordanita tenuicornis inhabits dry and warm habitats like mountain slopes, nutrient-poor grasslands, pastures, road side verges and similar places from the lowlands up to high mountains (2000m).

Life cycle:
Jordanita tenuicornis flies quite early in the season. I recorded them together with J. notata, A. mannii and Z. punctum in Sicily (500m) already in late April 2023 and in early May 2024. All species visited thistle flowers and those of the yellow Centaurea solsistalis. In the mountains the flight time may be delayed with increasing altitude until July. The larvae seem to enter an aestivation (July to September, in the mountains presumably shorter or none) and restart feeding in autumn. Hibernation is quite rapidly aborted in mild weather in the lowlands (with larvae mature already in March), but lasts longer in the mountains.

Remarks:
Jordanita tenuicornis is endemic to central and especially southern Italy including Sicily.

Hints on determination:
The males are easily recognized. They are very similar to those of J. graeca (relative thick antennae, narrow wings, way of flight), which misses in the area of tenuicornis. Thus the buzzing males are often already separable in flight from the more fluttering, broad-winged males of the always syntopical and abundant J. notata with their thinner antennae. In the habitat a third forester species (Adscita mannii) has been common, too. But these are much larger and have obtuse antenna tips.

The females are much more difficult and similar to J. notata. Thus genital examination is necessery. But in direct comparison the females are also a bit more narrow-winged, but much less striking than in males. These experiences have been made with populations of Sicily.


I thank Prof. Gerhard Tarmann for genital examinations (not only in this forester species).