Vascular Plants of North Carolina
Account for Blackfoot Quillwort - Isoetes melanopoda   Gay & Durieu ex Durieu
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Section 1 » Order Isoetales » Family Isoetaceae
AuthorGay & Durieu ex Durieu
DistributionThis species has a refined distribution from the more widespread one as portrayed in RAB (1968). According to Weakley (2018) and SERNEC specimens, it is confined just to the Piedmont in NC and is not present in the other two provinces. Some of the SERNEC specimens might not be correctly identified, and the website editors have not incorporated all of them onto the map below, as one editor (Sorrie) has gone over specimens to winnow down the range as best as possible. For now, the species is limited to scattered counties in the northeastern and southern Piedmont.

This Southeastern species occurs from southern NJ (disjunct there) and central VA south to southern GA and MS.
AbundanceApparently quite rare in the eastern and southern Piedmont, and possibly absent elsewhere -- based on Weakley (2018). Obviously, the abundance in the state is not clear at the present time. It has been added to the NCNHP's Watch List in 2022.
HabitatThe habitats in VA are "Seasonally flooded swamp forests, sluggish streams, and poorly drained flatwoods" (Digital Atlas of the Virginia Flora website). One recent population in Union County, NC, was in drying creeklets within a moist hardwood forest (Sorrie 12571).
PhenologyFruits from July to September.
IdentificationAll Isoetes species are quite grass-like, with numerous very slender and grass-like leaves growing from a common base. Most importantly, they are swollen at the base, where the megaspores are present, the key structure for separation of species. The leaves are terete (rounded) and hollow. For identification, see the key in Weakley (2018).
Taxonomic CommentsThough this species has been named for many decades, including in RAB (1968), what was considered as I. melanopoda in that reference is not the same as now designated by Weakley (2018) and some other recent references, as undoubtedly many of those older records have now been assigned to other species. All NC material is referrable to the eastern subspecies silvatica; according to Weakley (2020), this taxon is likely to be elevated to full species status, but in the meantime we will for convenience stick with "melanopoda".

All Isoetes species are quite grass-like, with numerous very slender and grass-like leaves growing from a common base. Most importantly, they are swollen at the base, where the megaspores are present, the key structure for separation of species. The leaves are terete (rounded) and hollow. For identification, see the key in Weakley (2018).
Other Common Name(s)Eastern Blackfoot Quillwort
State RankS1S3
Global RankG5
State Status[W7]
US Status
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B.A. SorrieUnion Co., W side of SR 1377, muddy clay of creek channel, under hardwoods. Mat 2010. UnionPhoto_natural
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