‡ Trioza erytreae (Del Guercio, 1918)

Distribution Portugal. Mainland: Aveiro (DGAV 2024; iNaturalist, Appendix 1); Beja (DGAV 2024; Duarte et al. 2024); Braga (DGAV 2024); Coimbra (DGAV 2024; iNaturalist, Appendix 1); Faro (DGAV 2024; Duarte et al. 2024); Leiria (DGAV 2024); Lisbon (DGAV 2024; iNaturalist, Appendix 1); Porto, Santarém (DGAV 2024); Setúbal (DGAV 2024; Duarte et al. 2024; iNaturalist, Appendix 1); Viana do Castelo, Vila Real, Viseu (DGAV 2024). Madeira: Madeira Island (Aguiar et al. 2019; iNaturalist, Appendix 1); Porto Santo (Aguiar et al. 2019).

Host plants Portugal. Rutaceae: Citrus × aurantium L., Citrus × aurantium f. aurantium L., Citrus × aurantium f. deliciosa (Ten.) M.Hiroe, Citrus × limon (L.) Osbeck, Citrus trifoliata L. (Duarte 2022; Duarte et al. 2024).

Comments. Most of the records were obtained through symptom visualisation on citrus trees as they are easy to detect. Although present in most districts of the Portuguese mainland, the distribution of T. erytreae is restricted to the western coastline. North of Lisbon it was found up to 85 km from the sea. South of Lisbon, the maximum distance from the sea was only about 15 km. This distribution is regularly updated by the Portuguese agencies of agriculture in DGAV (2024). Now, owing to successful control by the parasitoid Tamarixia dryi (Waterston) ( Hymenoptera: Eulophidae), T. erytreae is hard to find in northern Portugal and has not been detected in the south since October 2021 (DGAV 2024; Duarte et al. 2024).

⁂ ‡ Trioza eugeniae Froggatt, 1901

(Figs 22–24, 27, 29, 30)

Material examined. Faro: 2♂, 2♀, 4 immatures, Aljezur, 37°18'46.4"N 8°47'30.1"W, 2.v.2021, Melaleuca sp. (leg. B. Duarte) (BDC, dry mounted); 1♀, Tavira, Brejo, 37°06'13.8"N 7°44'15.2"W, 28.iv.2021, Citrus sinensis (leg. B. Duarte) (BDC, dry mounted); 1♀, Praia do Barril, Santa Luzia, 8.ix.2024, M. armillaris (leg. B. Duarte) (BDC, 70% ethanol); 2♂, 1♀, between Casais and Cercada, 37°17'18.2"N 8°35'57.5"W, garden, hedges, vegetation along unsurfaced road, Quercus suber plantation, M. armillaris (leg. D. Burckhardt & D.L. Queiroz) (NHMB, dry mounted); 3♂, 5♀, Várzea de Aljezur, 37°18'19.8"N 8°47'52.1"W, 9–12.ix.2024, M. armillaris (leg. D. Burckhardt & D.L. Queiroz) (NHMB, 70% ethanol); 37♂, 33♀, 8 immatures, Vale da Telha, Arrifana, 37°18'43.9"N 8°51'54.0"W, 12.ix.2024, maquis shrubland between garden and houses, M. armillaris (leg. D. Burckhardt, B. Duarte & D.L. Queiroz) (BDC, NHMB, dry mounted and 70% ethanol).

Distribution Portugal. Mainland: Faro (this study); Santarém (iNaturalist, Appendix 1).

Host plants Portugal. Myrtaceae: Melaleuca armillaris (Sol. ex Gaertn.) Sm. (this study) (Figs 25, 26).

Parasitoids. Some parasitised immatures were observed (Duarte 2022) but no hymenopterans emerged for obtaining an identification.

Comments. New for Europe and Portugal. Trioza eugeniae is an Australian species that was confused with T. adventicia Tuthill, 1952 prior to the study by Taylor & Martoni (2019). The latter species, also of Australian origin, was described from New Zealand (Tuthill 1952) and has been reported from the USA (as T. eugeniae). Taylor & Martoni (2019) redescribed the two species and suggested that T. curta (Ferris & Klyver, 1932), another Myrtaceae-inhabiting species described from New Zealand, is morphologically identical to T. eugeniae but differs slightly at the molecular level. Here we list some additional characters by which T. eugeniae can be separated from T. adventicia: male proctiger massive (Fig. 27) (versus relatively slender, Fig. 28); male subgenital plate, in lateral view, subglobular (Fig. 27) (versus triangular, Fig. 28); paramere with a long slender apex (Figs 27, 29) (versus short and blunt, Figs 28, 31); proximal segment of aedeagus wide in distal three-quarters (Fig. 27) (versus narrow, Fig. 28); and distal segment of aedeagus slender apically (Fig. 30) (versus inflated, Fig. 32). The characters given here for T. eugeniae fit also the description of T. curta by Ferris & Klyver (1932), confirming the conclusion by Taylor & Martoni (2019) that the two species are morphologically almost identical.

Taylor & Martoni (2019) listed Syzygium smithii (Poir.) Nied. ( Syzygieae) (type series) and Backhousia myrtifolia Hook. & Harv. ( Backhousieae) as confirmed hosts of T. eugeniae . Here we add Melaleuca armillaris ( Myrtaceae). The three host taxa are not closely related, making T. eugeniae a widely oligophagous species, a feature also present in the closely related T. adventicia (Taylor & Martoni 2019) .

Trioza eugeniae has been observed in Portugal for about four or five years (B.Z. Duarte, G. Duarte, pers. obs.), where it was found to be always associated with Melaleuca armillaris, not inducing any galls, never with any other Myrtaceae . Melaleuca armillaris originates from Australia (New South Wales, South Australia, Tasmania, Victoria) and was introduced into continental Portugal as an ornamental plant.