3. Physalis grisea (Waterfall) M. Martínez (syn.: P. pubescens var. grisea Waterfall) (N-Am.) – A very rare, probably always ephemeral alien. First recorded as a wool alien in the Vesdre valley near Ensival in 1909 (as Physalis peruviana). Recorded along river Maas near Kotem in 2003, probably from discarded kitchen waste (as Physalis angulata). In 2010 also observed in Mol (see: http://waarnemingen.be/waarneming/view/49363576) and in 2011 on the gravelly borders of river Maas near Boorsem (Maasmechelen).
Physalis grisea is poorly known and possibly overlooked. Its fruits are eaten and it possibly occurs more often on dumps or sewage works. Confusion is most likely with Physalis peruviana and P. pubescens. From the former it is readily distinguished by its much smaller flowers but it is hardly separated from the latter (see key).
The taxonomic position of Physalis pruinosa L. is unclear. It is sometimes considered an older synonym of P. grisea (and thus would have priority). However, most recent authors seem to accept it as a distinct species. According to Raju & al. (2007) it is morphologically very similar to P. grisea but unlike the latter not grown as a vegetable. As overview of distinguishing features are provided by these authors.
Halvorsen R. & Grøstad T. (2004) Physalis grisea (Waterf.) M. Martinez, en ny art va slekta Physalis L. i Norge. Blyttia 62(3): 171-173.
Martínez M. (1998) Revision of Physalis section Epeteiorhiza (Solanaceae). An. Inst. Biol. Univ. Nac. Aut. México, ser. Bot. 69(2): 71-117.
Raju V.S., Reddy C.S. & Rajarao K.G. (2007) The myth of “minima” and “maxima”, the species of Physalis in the Indian Subcontinent. Acta Phytotax. Sinica 45(2): 239-245. [available online at: https://www.researchgate.net/publication/258912061_The_myth_of_minima_an...
Svenson A. (2002) Physalis grisea – rätt namn på gyllenbär. Svensk Bot. Tidskr. 96(5): 223-225.