Summary ⁸

Nitellopsis obtusa is a large freshwater alga. It is also known by the common name starry stonewort.

Biology ⁹

This stonewort is usually a summer annual, but in some years, if the winter is mild, it may not fully die back. This species very rarely produces spores. It is thought that spore production is controlled by light levels, and tends to take place from July to September. This species spreads mainly by means of the star-shaped bulbils that occur on the lower stem nodes. These bulbils stay viable for several years.

Growth Form ¹⁰

Algae/nonvascular plant.

Habitat ¹⁰

Generally prefer still water with low nutrient levels and an exposed silt or clay soil. Submersed and attached to the sediments by root-like rhizoids, found throughout Indiana. Limestone accumulates on the plant giving it a calcified, brittle texture.

Leaves ¹⁰

It has no true leaves, but needlelike structures along the stem that look like leaves (internodal cells).

Reproductive Mode ¹⁰

This is not a flowering plant. Starry stonewort has small, white, star-shaped rhizoids (bulbils, not flowers), and can spread by fragmentation of nodes.

Control Considerations ¹⁰

Invasive species that is very difficult to control. It can be confused with Chara species, but starry stonewort has small, white, star-shaped rhizoids (not flowers) that are not present on Chara.

Sources and Credits

1. (c) fabelfroh, some rights reserved (CC BY-NC-SA), https://www.flickr.com/photos/fabelfroh/2477981227/
2. (c) anonymous, some rights reserved (CC BY-NC), https://eol.org/media/10817087
3. (c) Purdue University, all rights reserved, uploaded by Purdue University
4. (c) anonymous, some rights reserved (CC BY-NC), https://eol.org/media/10817088
5. (c) anonymous, some rights reserved (CC BY-NC), https://eol.org/media/10817089
6. (c) anonymous, some rights reserved (CC BY-NC), https://eol.org/media/10817090
7. (c) anonymous, some rights reserved (CC BY-NC), https://eol.org/media/10817091
8. Adapted by Max Leveridge from a work by (c) Wikipedia, some rights reserved (CC BY-SA), https://en.wikipedia.org/wiki/Nitellopsis_obtusa
9. Adapted by Max Leveridge from a work by (c) Wildscreen, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/20378804
10. (c) Max Leveridge, all rights reserved

More Info

• iNat taxon page
• Biodiversity Heritage Library
• BOLD Systems BIN search
• Global Biodiversity Information Facility (GBIF)
• HOSTS - a Database of the World's Lepidopteran Hostplants
• NatureServe Explorer 2.0
• NBN Atlas
• SEINet Symbiota portals
• Tropicos

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