''Isoetes echinospora'', also known as spiny quillwort, spiny-spored quillwort or spring quillwort is a species of

quillwort ''Isoetes'', commonly known as the quillworts, is the only extant genus of plants in the family Isoetaceae, which is in the class of lycopods. There are currently 192 recognized species, with a cosmopolitan distribution but with the individual s ...

in the

Isoetaceae Isoetaceae is a family including living quillworts (''Isoetes'') and comparable extinct herbaceous lycopsids (''Tomiostrobus ''Tomiostrobus'' is an extinct quillwort genus from the Early Triassic of Australia, China and Russia, which was espe ...

family, and is the most abundant species in Canada. It can be found in shallow aquatic environments from Labrador and Newfoundland to Alaska, and south to Pennsylvania, Wisconsin, Colorado, and California. In Germany it is found in only two locations: the

Feldsee The Feldsee (also ''Feldbergsee'') is a lake in southern Baden-Württemberg at the foot of the Feldberg east of Freiburg im Breisgau in Germany. It is part of the Southern Black Forest Nature Park. Geology and earth history The Feldsee ...

and Lake

Titisee The Titisee is a lake in the southern Black Forest in Baden-Württemberg. It covers an area of and is an average of deep. It owes its formation to the Feldberg glacier, the moraines of which were formed in the Pleistocene epoch and nowadays for ...

, both in the High

Black Forest The Black Forest (german: Schwarzwald ) is a large forested mountain range in the state of Baden-Württemberg in southwest Germany, bounded by the Rhine Valley to the west and south and close to the borders with France and Switzerland. It is t ...

.Information Board at the Feldsee. Recorded on 26 Aug 2015. It bears 10–30 green to yellow leaves and a two-lobed

corm A corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ' ...

. The

velum Velum may refer to: Human anatomy * Superior medullary velum, anterior medullary velum or valve of Vieussens, white matter, in the brain, which stretches between the superior cerebellar peduncles ** Frenulum of superior medullary velum, a sligh ...

covers one to three quarters of the sporangium, which are long. Round white

megaspore Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. These plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a female gamet ...

s are about in diameter and are covered with spines. Kidney-shaped

microspore Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote. Megasp ...

s are about long with smooth, fine spines. European populations of the plant lack the stomata present in North American populations. ''Isoetes muricata'' and ''Isoetes echinospora'' var. ''braunii'' refer to the North American plants, but are often considered synonyms of Europe's ''I. exhinospora''.

References

echinospora Flora of North America Flora of Germany {{Lycophyte-stub