Global description
Physalis lagascae is a decumbent, finely pubescent plant with single and alternate leaves, long petiolate. The blade is oval, with apiculate apex, base attenuated and sinuous and toothed margin. The flowers are solitary and campanulate. The fruit is a berry included in the calyx transformed into a hanging vesicle. The seeds are lenticular.
Cotyledons
The cotyledons are oval lanceolate. They are borne by a pubescent petiole, 4 to 6 mm long. The blade is glabrous, finely pubescent on the margin, 6 mm long and 4 mm wide.
First leaves
The first leaves are simple and alternate. They are long petiolate. The blade is oval to lanceolate, 2 to 3 cm long and 10 to 15 mm wide. The margin is sinuous to irregularly toothed and pubescent. The lower face of the blade is pubescent, especially along the veins. The stem is small, soft and finely pubescent.
General habit
Physalis lagascae is erect. The plant forms a small, abundantly branched but often decumbent bush, rarely exceeding 50 cm in height.
Underground system
The root is a taproot.
Stem
The stem is polygonal and hollow. It is slender and soft, light green in color, almost translucent. It is finely pubescent.
Leaf
The leaves are simple and alternate. They are borne by a petiole 3 to 5 cm long. The blade is oval to elliptical, more or less apiculate at the apex and attenuated at the base. It is 5 to 8 cm long and 2 to 4 cm wide. The margin is sinuous and irregularly toothed. The blade is marked with 4 to 6 pairs of pinnate veins. Both sides are finely pubescent, at least along the veins and margin at the lower face.
Flower
The flowers are solitary and axillary, located at the intersection of the ramifications of the plant. They are borne by a pubescent peduncle, 3 to 4 mm long. The calyx, 3 mm long, consists of 5 sepals welded in section at the base and ending in 5 short triangular teeth. The chalice is pubescent. The corolla is campanulate, formed of 5 welded petals. It is 4-5 mm wide and creamy white with a purple spot at the base of the petals. The stamens are inserted into the corolla tube alternately with the petals. The ovary includes 2 boxes with many eggs.
Fruit
The fruit is a berry 6-8 mm in diameter, yellow in color and containing many seeds. This berry is included in the calyx which has turned into a vesicle, obconic, pendulous, 8 mm wide and 13 to 15 mm long. This vesicle is pubescent, it is first of green color then browns and dries at maturity. It is traversed by 7 or 8 longitudinal ribs connected by a network of fine ribs.
Seed
The seeds are flat and lenticular, with a diameter of 2 mm. The tegument is orange in color and finely alveolate.