2. Physalis angulata L. (trop. Am.) – A rare and ephemeral alien. First recorded in 1961 on waste land near Oud-Turnhout. From 1991 onwards increasingly recorded in port areas (especially in Gent and Antwerpen, exceptionally elsewhere), always associated with soybean importation. Some years rather common near grain stores, under conveyors, in road verges or on unloading quays. Recorded in 1995 in a maize field in Herk-de-Stad (along with Sida spinosa), probably introduced with manure.
Physalis angulata is a fairly variable species. It is often said to have unspotted corollas (Waterfall 1958) but this obviously does not hold true. Most Belgian plants have yellowish corollas with greenish or brownish patches in their throats (see also van Ooststroom & Reichgelt 1962). Such plants somehow look like Physalis cordata Mill., another American weed that might occur one day in Belgium. The latter is distinguished by its fruiting calyx with 5 angles (distinctly 10-angled in P. angulata). Plants with very long and slender fruiting pedicels (up to 40 mm long) are sometimes segregated as Physalis pendula Rydberg (syn.: P. angulata var. pendula (Rydberg) Waterfall) (see also Clement & Foster 1994). However, according to Sullivan (2004) intermediates are commonly encountered and modern accounts merely include this in P. angulata (Pretz & Deanna 2020). Typical plants of var. pendula have been recorded in 1995 and 2000. Finally, plants with narrow leaves (linear-lanceolate) and smaller corollas (ca. 8 mm across and with anthers at most 2 mm long) have been distinguished as Physalis lanceifolia Nees (syn.: P. angulata var. lanceifolia (Nees) Waterfall) (Ward 2008). This taxon possibly also occurs in Belgium.
Older Belgian records from the valley of river Vesdre (as wool aliens; see Visé 1942, Visé 1958, Lambinon & al. 1959) all proved to be erroneous and belong in fact to the similar Physalis ixocarpa (see under that species).
Clement E.J. & Foster M.C. (1994) Alien plants of the British Isles. BSBI, London: XVIII + 590 p.
Lambinon J., Lawalrée A., van Ooststroom S.J. & Reichgelt Th.J. (1959) Adventices lainières récoltées dans la vallée de la Vesdre en 1959. Lejeunia 23: 149-154.
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...
Pretz C. & Deanna R. (2020) Typifications and nomenclatural notes in Physalis (Solanaceae) from the United States. Taxon 69(1): 170-192. [available online at: https://onlinelibrary.wiley.com/doi/10.1002/tax.12159]
Sullivan J.R. (2004) The genus Physalis (Solanaceae) in the southeastern United States. Rhodora 106: 305-326.
Visé A. (1942) La flore adventice de la région de Verviers. Lejeunia 6: 99-119.
Visé A. (1958) Florule adventice de la vallée de la Vesdre. Bull. Soc. Roy. Bot. Belg. 90: 287-305.
Van Ooststroom S.J. & Reichgelt Th.J. (1962) De in Nederland adventieve en gekweekte Physalis-soorten. Gorteria 1(7): 65-71.
Verloove F. & Vandenberghe C. (1993) Nieuwe en interessante graanadventieven voor de Noordvlaamse en Noordfranse flora, hoofdzakelijk in 1992. Dumortiera 53-54: 35-57.
Ward D.B. (2008) Keys to the flora of Florida: 19, Physalis (Solanaceae). Phytologia 90(2): 198-207.
Waterfall U.T. (1958) A taxonomic study of the genus Physalis in North America north of Mexico. Rhodora 60: 107-114, 128-142, 152-173.