Walkerella microcarpae Bouček, 1993

Pérez-Gómez, Álvaro, Sánchez-García, Íñigo, Royo, José Manuel, Rasplus, Jean-Yves & Robla, Jairo, 2025, Unveiling an intricate relationship: Ficus trees, their associated wasps (Hymenoptera, Chalcidoidea) and another story of invasion in the Iberian Peninsula and Europe, Journal of Hymenoptera Research 98, pp. 667-687 : 667-687

Walkerella microcarpae Bouček, 1993

Material studied.

Spain: • Cádiz: Jerez de la Frontera ( Zoobotánico de Jerez ): 3 ♂ + 3 ♀ ex., Í. Sánchez leg. and MNCN_Ent 235063 deposit., 7-XII-2018, 82 m a. s. l., found in dissected syconia of Ficus microcarpa (36.689315, -6.150638) . • Alicante: San Vicente del Raspeig ( Universidad de Alicante ): 11 ♀ + 5 ♂ ex., J. M. Royo leg. and AC deposit., 5-VII-2023, 92 m a. s. l., found dissecting fallen syconia of Ficus microcarpa and some flying specimens close to the tree (38.384264, -0.512455). See in Fig. 1 B .

Ecological remarks.

Gall-forming wasp in figs of Ficus microcarpa .

Distribution.

This species probably originates from the Oriental region and was introduced to the Palearctic and the Nearctic ( Ma et al. 2013). In Europe, it is only known from the Canary Islands (Tenerife) ( Carnero Hernandez et al. 1998), Majorca ( Wang et al. 2015 a), as well as Cyprus ( Demetriou et al. 2023) and Greece ( Koutsoukos et al. 2025). As the reports by Falcó-Garí et al. (2010) from eastern Iberian Peninsula have no localities, we consider this as a first confirmed record for the Iberian Peninsula.

Short description.

Difficult to separate morphologically from other genera of European Pteromalidae . Walkerella is recognized by the following characters: body blackish, without conspicuous external ovipositor and apterous males with long mandibles. The genus Otitesella is also present in the Palearctic region (associated with Platyscapa ). Also, the genus Micranisa from Greece and Cyprus ( Demetriou et al. 2023; Koutsoukos et al. 2025), which is quite close to Walkerella , although is easily separated by its ovipositor which is extended and curved downwards.

Figures

Figure 1. Wasps cited in this work A female of Eupristina aff. verticillata Waterston, 1921 B Walkerella microcarpae Bouček, 1993 C female and D male of Pleistodontes imperialis Saunders, 1883 E female and F males of Philotrypesis okinavensis Ishii, 1934 G Eufroggattisca okinavensis (Ishii, 1934) H Josephiella microcarpae Beardsley & Rasplus, 2001.