Author | (Fassett) Epling | |
Distribution | Limited to the eastern half of the Piedmont, as far as known. There are now three "tiny" species of skullcaps in the Southeast -- Scutellaria australis, S. leonardii, and S. parvula. The old S. parvula (e.g., in RAB 1968) has been split into these three species. Older keys rendered Identification tricky, but the key in Weakley et al. (2022) is good. Specimen determinations at NCU (University of North Carolina herbarium) indicates that S. australis has been collected from just four counties in NC, all close to the Fall Line -- Orange, Lee, Richmond, and Stanly counties. NCU has more specimens of S. leonardii, but apparently none of S. parvula (strict sense). In late April 2023 Becky Dill discovered a large population in mafic soil in Anson County; she made a collection and took photos. An iNaturalist photo in 2019 by Kevin Metcalf from Mecklenburg County also appears to be this species and not S. parvula, which has not been documented for the state; it is clearly not S. leonardii.
This species supposedly ranges from NC and KY south to northern FL and eastern TX. It is not known from VA. | |
Abundance | Rediscovered in NC in 2019 and in 2023; thus, the State Rank went from SH to S1. All prior records are several decades old, and until 2023 the NCNHP treated it as SH (Historical) in late 2022. However, it is legally protected as a State Endangered species. The Anson Co. population is estimated to be 300+- plants by Dill and Sorrie. | |
Habitat | Specimen records indicate that in NC this is a species that often lives near streams or rivers (near Falls of Yadkin River, RR embankment near Deep River, edge of Morgan's Creek in Orange Co.), but only rarely in actual bottomlands ("swamp forest Cartledges Creek" in Richmond Co.). The Anson Co. population occurs on a roadside in moist pebbly soil only 1" deep to mafic bedrock. This contrasts with S. leonardii, which occurs on dry soil of roadbanks, glades, and other similar places with little competition. However, the 2023 plants in Anson County were growing in full sun in a mowed right-of-way among plenty of competition. Other mafic-loving plant species growing with it include Baptisia alba, Oenothera linifolia, Marshallia obovata, Agave virginica, Helianthus schweinitzii. Habitat for the 2019 record is not known. | |
Phenology | Blooms from late April to July, and fruits shortly after flowering. | |
Identification | This species can be confused in the field (and in the literature), with the other two dwarf species in the genus -- S. leonardii and S. parvula, so pay attention to details. It grows to about 6-8 inches tall (shorter where mown), often with a 1-few branches, but quite slender. It has numerous pairs (opposite) stem leaves, being ovate to almost round -- quite different from those of the other two species whose leaves are triangular-ovate -- about 2/5-inch long and across, sessile at the base. Also, there are 3-5 lateral veins on each side of the midrib, with them anastomosing (joining others into a complex pattern). The leaves are quite pubescent, as is the stem, unlike then other 2 species. From the upper leaf axils grow the quite small blue flowers, each one about 1/3-inch long. In S. leonardii, the primarily one in the state, the leaves are lanceolate and about 2-3 times longer than wide, entire and usually glabrous and clearly ascending; there are just 1-2 veins on each side of the midrib. In S. parvula, reported in the state but not confirmed, the leaves are triangular-ovate, quite glabrate, with 3-5 veins on each side of the midrib but not anastomosing. One good feature that helps detection in the field is the dull red "horseshoes" of the mature calyces. Good luck finding either S. australis or S. parvula in the state; any dwarf species is presumed to be S. leonardii until or unless proven otherwise. These species are very difficult to spot, even in flower; it is often the capsule that more readily catches the attention than does the flower. | |
Taxonomic Comments | Scutellaria australis has often been considered simply as a variety of S. parvula; NatureServe does consider it as a species but with a Q on the Global Rank for Questionable taxonomy. Note, however, that even in the middle of the 20th Century, Gleason (1952) considered all three as good species, as do many or most modern references, including Weakley (2018).
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Other Common Name(s) | None | |
State Rank | S1 | |
Global Rank | G4T4? [G4?] | |
State Status | E | |
US Status | | |
USACE-agcp | | |
USACE-emp | | |