Gracillaria syringella (Fabricius, 1794)

Gracillaria syringella (Fabricius, 1794) View in CoL

( Fig. 1 View Fig ),

was observed on 05.07.2024, during light-trapping for moths at Herdade da Mitra (Valverde, Évora, Portugal). The area surrounding the light-source consists of dry Mediterranean parkland, dominated by sclerophyllous oak-species, namely Quercus rotundifolia and Q. suber , whilst a riverine habitat nearby is dominated by narrow-leaved ash, Fraxinus angustifolia . Minor traditional agricultural activities are present, such as non-intensive olive trees’ cultivation, and honey bee hives.

The aforementioned record triggered a search for published and unpublished records of G. syringella in Iberia, resulting in the finding of five hitherto unpublished records, otherwise only available in online biodiversity databases such as iNaturalist.org and Observation.org ( Table 1 View Table 1 ).

Discussion

Gracillaria syringella is a characteristic moth, whose identity in Europe can only be disputed against some dark-colored Caloptilia and the only congeneric species, G. loriolella Frey, 1881 . However, it bears a richer, brownish ground-color against the plainer-grey of the latter species and larger white streaks, often forming larger blotches. All these Gracillariidae rest in a characteristic posture, where the anterior part of body and head are raised above the substrate, standing on the first two pairs of legs.

Despite being relatively easy to identify, records of the species in Iberia are few and apparently hitherto formally unpublished, so that previous to our Portuguese record, only five could be found. However, although the preferred host plant, lilac ( Syringa vulgaris ), is not native to the region and is only present as a garden or often naturalized shrub, alternative native Oleaceae are widespread in western Iberia, especially narrow-leaved ash ( Fraxinus angustifolia Vahl, 1804 ), a common tree in Portugal ( Ara ̇jo et al., 2024), and widely cultivated species of privets, chiefly Ligustrum vulgare , L. lucidum or L. ovalifolium . Although never reported, some hard-leaved species in the same family are also potential hosts, such as Phillyrea spp. , Jasminum fruticans or even Olea europaea .

Regardless of the origin and ecology of this species in Iberia, it is clear that further field-work is necessary in order to precise which host plant it is using both in north Iberia, as well as in the south.