The Apertochrysa prasina group (Neuroptera: Chrysopidae), with a key to the European species Author Duelli, Peter 0000-0001-8862-8262 Biodiversity and Conservation Biology, Swiss Federal Research Institute WSL, Zu ̈ rcherstrasse 111, CH- 8903 Birmensdorf ZH, Switzerland. peter. duelli @ wsl. ch; https: // orcid. org / 0000 - 0001 - 8862 - 8262 peter.duelli@wsl.ch Author Henry, Charles S. 0000-0001-7297-9703 Department of Ecology and Evolutionary Biology, University of Connecticut, Unit 3043, 75 North Eagleville Road, Storrs, CT 06269 - 3043, USA. charles. henry @ uconn. edu; https: // orcid. org / 0000 - 0001 - 7297 - 9703 charles.henry@uconn.edu text Zootaxa 2022 2022-05-09 5134 1 61 91 journal article 55630 10.11646/zootaxa.5134.1.3 a13639ac-223e-4ffe-9cae-007a1b397482 1175-5326 6531298 4B68EA16-6738-431E-BFFF-4CF9FB4FBB41 Apertochrysa ‘Ap3’ (temporary name) ‘greenhead’ partim (Duelli and Obrist, 2020) ‘pp3’ (Duelli and Henry, 2021) Diagnosis: Available live-colored material: 37♀ , 46♂ ( Switzerland, Italy, France , Austria ) A medium to large-sized lacewing species with mostly bluish-green body coloration, but sometimes grass-green or locally bright green. Tips of palps dark brown. Frons, scape and clypeus glossy green. Subantennal sutures pale. A majority of specimens examined had a roundish (mostly pear-shaped) interantennal spot, but about a third had triangular spots. Black dots on the scape occur regionally ( Fig. 15 ), which might be the effect of an alternative allele. Individual females can produce offspring both with scape dots and without. The green or rarely yellowish vertex never bears dots. Female forewings measure 12.5–16.0 mm, male forewings 10.5–14.0 mm. The costal crossveins often are 100% dark, but specimens with only 40% dark have been observed. The males have no furwings, which helps to distinguish them from A. prasina males of similarly large size. The im cell is formed by veins, which are usually 12–40% dark, clearly different from either A. abdominalis with 80–100% dark im veins or A. prasina with less than 12% dark veins. The dark portions of the im veins are usually on different veins, while in A. prasina , A1, and A2 the dark portion tends to be on one vein only ( Fig. 10 ). All gradate crossveins are darker than the longitudinal wing veins. There is normally one pair of large black (rarely brown) spots on the prothorax. The lateral prothoracic spots also are mostly large and black; sometimes the first (anteriormost) one is larger than the other and brown. The dorsal spots on the abdomen are usually black, but their number and size can vary. There are populations with hardly any dots, but most populations have two pairs of black dots per segment. The black lateral marks on the abdomen can build an almost continuous line, or they can form a downward hook (“hockey stick”) on most segments ( Fig. 15 ). The ventral side of the abdomen is green with black setae. The eggs are deposited singly and the larvae enter diapause as third instars. Distribution: This species is thus far known from Europe and central Asia. Ap3 is probably the most widespread prasinoid species in the western Palearctic region. It was found from Spain to Kyrgyzstan and from the Mediterranean coast to central Europe. In northern Italy (Badano, unpublished) and southern Switzerland , a morph was found where the males do not have a triangular prothorax as in all other prasinoid males, but a more rectangular prothorax similar to that of the female. Otherwise, they look like ordinary specimens of Ap3. The two forms coexist syntopically in southern Switzerland , without hybrid forms, and thus the rectangular male prothorax might be an alternative allele, or represent a different species. In fact, some specimens with traces of pink in the subantennal sutures were found but only in the strain with rectangular male prothorax.