Genus: Isoetes — quillwort

You need to examine the size and ornamentation of mature megaspores, found in the expanded leaf bases, in order to identify most quillwort species. For most New England taxa, it is best to collect ripe megaspores from August onward. Check the condition of the megaspores while in the field to ensure that mature spores are available; they should be spherical and bone-white upon drying. Hybrids can occur where two or more species are found in the same water body. Hybrids usually have variably shaped megaspores, which range from spherical to pyramidal and flattened. References: Eaton (1900), Kott and Britton (1983), Taylor et al. (1993).

Family

Isoetaceae (quillwort family)

This genus’s species in New England

• Isoetes acadiensis
• Isoetes echinospora
• Isoetes engelmannii
• Isoetes hieroglyphica
• Isoetes lacustris
• Isoetes prototypus
• Isoetes riparia
• Isoetes tuckermanii

Visit this genus in the Dichotomous Key

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