Physalis philadelphica (California, USA)
Physalis philadelphica, the tomatillo 
The tomatillo fruit is surrounded by a paper-like husk formed from the calyx. As the fruit matures, it fills the
husk and can split it open by harvest. The husk turns brown, and the fruit can be any of a number of colors when ripe, including yellow, red, green, or even purple.
Tomatillos are the key ingredient in fresh and cooked Latin American green sauces. The freshness and greenness of the husk are quality criteria. Fruit should be firm and bright green, as the green colour and tart flavour are the main culinary contributions of the fruit.  
Common names: husk-tomato, large-flowered tomatillo, tomatillo ground-cherry  
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Physalis philadelphica Lam., Encycl. 2: 101. 1786.
Annual branched herb, sparsely pubescent to glabrescent; leaves ovate, up to 8 cm long, up to 6 cm broad, base cordate, margin unequally dentate; pedicel up to 8 mm long; calyx campanulate, split halfway, 8 mm long, 10 mm wide; corolla pale yellow, spotted in throat, 10-30 mm in diam.; filaments 5 mm long; anthers 3-5 mm long, bluish to purplish; style 8 mm long; fruiting calyx 2-3 cm long, weekly 5-angled; beryy globose.
Photographed from California