http://www.eje.cz as "emerald ash borer". This species has invaded North America (Haack et al., 2002) and Europe (Baranchikov et al., 2008) causing widespread mortality of ash and was assessed as "the most costly biological invasion by an exotic forest insect to date" (Herms & McCullough, 2014). Notably, the herein reported NYC Agrilus was attacking a nonnative tree growing in the heart of a large urban conglomerate not too distant from a major international trade port. These observations were consistent with a hypothesis that the unknown NYC Agrilus might be yet another unwanted human-mediated addition to the Nearctic fauna, potentially capable of infl icting damage to an important urban tree in parts of North America. Preliminary morphology-based identifi cation (see Material and methods and Results) suggested that the NYC Agrilus adults belong to the A. roscidus species-group (ARSG, as defi ned in Jendek & Grebennikov, 2011) with 13 species-group taxa (Table 2). Members of the ARSG are externally similar among themselves and their reliable species-level morphological identifi cation is based on male characters. The most important diagnostic characters are body size and color, shape of antennomeres, shape of pronotum, type and length of prehumerus, shape of aedeagus