Hottonia

Water spring ( Hottonia palustris)

The water springs ( Hottonia ) are a genus of the family of Primrose ( Primulaceae ) within which they are the only aquatic plants. The genus consists of only two species that are native to North America and Eurasia.

Description

Water springs are perennial, herbaceous aquatic plants. The submerged, bare leaves are pinnate, alternate or whorled stand, the individual lobes are linear, young leaves are curled at the edges down.

The doldige inflorescence stands at a towering over the water surface inflorescence stem, the flowers are place in several whorls that overlap each other. The hermaphrodite flowers are heterostyl. The crown is white to pink and can be both longer and shorter than the calyx. The Corolla lobe are spread out and notched. The stamens are adherent to the corolla tube. The scar is capitate.

The fruit capsule opens at the side, it contains only a few seeds with reticulated relief.

As the number of chromosomes occurs 2n = 20 and 22 respectively.

Distribution and systematics

The genus consists of two species which are native to North America and Eurasia.

• Water spring ( Hottonia palustris L.): Eurasia
• Hottonia inflata Elliott: North America

Botanical history

The scientific genus name was given by Hermann Boerhaave Hottonia in memory of Peter Hotton and later taken over by Carl Linnaeus.

Evidence

• A. A. Anderberg: Primulaceae. In: Klaus Kubitzki (ed.): The Families and Genera of Vascular Plants - Volume VI - Flowering Plants - Dicotyledons - Celastrales, Oxalidales, Rosales, Cornales, Ericales, 2004, pp. 317, ISBN 978-3-540-06512 - 8