Map Snapshot
2 Records
Status
Rock Clubmoss is extirpated from Maryland. There was only one known population that was located along the Youghiogheny River in Garrett County. The last time the population was observed was back in 1982 along a wet outcrop by a waterfall (MD Heritage Program, 2018). Rock Clubmoss is most often found on the western edge of the of the central Appalachian Mountains with only scattered populations on the eastern edge of the Appalachians. Rock Clubmoss, according to Weakley's Flora of the Southeast is found on, "Rock outcrops and cliffs, especially in the spray of waterfalls, at low to medium elevations."
Description
Rock Clubmoss is very similar to Shining Clubmoss (Huperzia lucidula) and care must be taken when trying to identify the two species. In Maryland, Rock Clubmoss would only be found in Garrett County. Any Huperzia found off the Allegheny Plateau in Maryland is almost certainly Shining Clubmoss. The habitat of the two Huperzia species are also different. As noted above, Rock Clubmoss is found growing on rocky substrates usually near waterfalls while Shining Clubmoss can be found in a number of different habitats including hardwood forests and wooded swamps. The leaves of the two species are also different (a 10x hand lens is needed to really get a good look at the leaves). Rock Clubmoss has leaves that are oblanceolate (lanceolate with a blunt round tip) and Shining Clubmoss has leaves that are lanceolate. Shining Clubmoss has noticeable serrations on the edge of the leaves while Rock Clubmoss has leaf edges with few serrations that are much less defined (Weakley, 2015).
Seasonality Snapshot
Source: Wikipedia
| Rock firmoss | |
|---|---|
| |
| 1913 illustration[1] | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Lycophytes |
| Class: | Lycopodiopsida |
| Order: | Lycopodiales |
| Family: | Lycopodiaceae |
| Genus: | Huperzia |
| Species: | H. porophila
|
| Binomial name | |
| Huperzia porophila | |
| Synonyms[2] | |
| |
Huperzia porophila, the rock clubmoss or rock firmoss, grows throughout the Appalachian province of the Eastern United States and central Canada, from Ontario south to Georgia and Alabama. It is rare east of the Appalachians, being most common in a north–south belt along the western plateau area.[3]
Huperzia porophila grows only on or over rock and requires cool, moist, shaded, acid spots. It is a beautiful sight growing over boulders and outcrops. It is often confused with the shining firmoss (Huperzia lucidula) whose range it largely shares and which also often grows on rocks. The rock firmoss leaves, 3–8 mm long, are generally not shiny like those of the shining firmoss, and the ascending 12–15 cm stems are seldom branched. Unlike H. lucidula, it only grows as individual plants and not as dense colonies. One of the best sites for viewing this species is in the Hocking Hills in southeast Ohio.[4]
This species is of hybrid origin, the parents being Huperzia lucidula and Huperzia selago.
H. porophila hybridizes with H. lucidula to produce the sterile hybrid H. × bartleyi.
References
[edit]- ^ drawing from Britton, N.L., and A. Brown. 1913. Illustrated flora of the northern states and Canada. Vol. 1: 44.
- ^ The Plant List Huperzia porophila (F.E. Lloyd & Underw.) Holub
- ^ Biota of North America Program 2014 county distribution map
- ^ Flora of North America, Huperzia porophila (F. E. Lloyd & L. Underwood) Holub, 1985.
