Mimulus ringens var. colpophilus
|Allegheny monkey-flower, estuarine monkey-flower, square-stemmed monkey-flower|
|Elizabeth J. Farnsworth|
The following Participating Institutions are custodians for this species in the CPC National Collection:
New England Wild Flower Society
The conservation of Mimulus ringens var. colpophilus is fully sponsored.
Elizabeth J. Farnsworth contributed to this Plant Profile.
Mimulus ringens var. colpophilus is a variety of monkeyflower with a highly restricted distribution from Maine to Quebec. It grows only in freshwater wetlands, usually tidal areas with fluctuating water levels. As a possible adaptation to its specialized habitat, the plant has a compact architecture with short internodes (distances between leaf pairs along the stem) and small leaves. It is known only from twelve localities in the U. S. and its status in Quebec is largely unknown. Threats to the long-term survival of this species include destruction of its wetland habitat, sea-level rise leading to an increase in salinity, and competition from invasive wetland species.
Research and Management Summary:
Much more ecological and genetic work is needed on this taxon to determine its distribution, its distinctiveness as a taxon, its taxonomic relationship to other varieties within the Mimulus ringens complex, and its rarity and conservation needs.
Mimulus ringens var. colpophilus is a perennial, herbaceous plant with a square stem up to 1.3 m tall that arises from a rhizome. Leaves 2.5 to 5.0 cm long are arrayed oppositely on the stem at intervals of 1.5 to 2.5 cm. The showy, irregular, lavender-purple flowers vaguely resemble the flat, comical face of a monkey. In the variety colpophilus, the lobes of the calyx are only 1.5 to 2.5 mm long (half as long as variety ringens), and the flowers are borne on short pedicels only 1 to 1.7 cm long.
Distribution & Occurrence
Mimulus ringens var. colpophilus is found in muddy, tidal, river embayments of Merrymeeting Bay, Maine and the St. Lawrence river in Quebec (Gleason and Cronquist 1991, Haines and Vining 1998, NatureServe 2001). Merrymeeting Bay is a large estuary that is tidal but receives little salt influence (Haines 2001). Such freshwater tidal wetlands contain many specialized and rare plant species that are able to tolerate twice-daily tidal fluctuations, and are highly productive areas in terms of plant and animal biomass. Haines (personal communication) has observed Mimulus ringens var. colpophilus growing on a "mud and silt-covered cobble and ledge" in Merrymeeting Bay, associated with other herbaceous species normally found in freshwater tidal wetlands. Mimulus ringens (sensu lato) also occurs in Merrymeeting Bay, but typically on finer sediments. The species is also reported from Vermont, but no published information was available at the time of writing on its habitat there (NatureServe 2001).
|Twelve occurrences are recorded from Maine, and one herbarium record (at the New England Botanical Club collection, Cambridge, Massachusetts) from Vermont. The number of current occurrences in Quebec is not known. It is impossible to estimate global population numbers due to the paucity of information on this taxon.|
Conservation, Ecology & Research
It is known to be a rhizomatous perennials, but the degree to which it reproduces through vegetative perennation is unknown.
Flowering occurs during July and August (Magee and Ahles 1999). The flowers are bilaterally symmetrical and bluish-purple; given the floral morphology and the behavior of congeners, likely pollinators are bees (Karron et al. 1995). Mimulus ringens (sensu lato) is capable of selfing or outcrossing.
Inbreeding depression due to high rates of selfing has been noted in small populations of both Mimulus ringens (sensu lato) and Mimulus guttatus (Dudash et al. 1991, Carr and Dudash 1995, Karron et al. 1995, Carr and Dudash 1996, Carr et al. 1997). Isolated populations of Mimulus ringens var. colpophilus may be vulnerable to this phenomenon.
Several species of Mimulus have been used as model systems for understanding rapid evolution in response to environmental change, including increased heavy metal pollution (Allen and Sheppard 1971, Macnair et al. 1993, Tilstone and Macnair 1997). The tendency of Mimulus species to proliferate evolutionarily into several varieties may reflect rapid microevolution, and creates challenges for conservation (Carr and Fenster 1994).
Changing hydrology (tidal amplitude, quality and quantity of freshwater, etc.) in est
Jeffrey Karron (Department of Biology, University of Wisconsin, Milwaukee), is conducting several studies on the reproduction and evolution of Mimulus ringens (sensu lato).
Basic field research is critically needed on all aspects of the ecology, habitat requirements, reproductive biology, herbivory, and demography of Mimulus ringens var. colpophilus
Haines, A.; Vining, T.F. 1999. Flora of Maine. Bar Harbor, Maine: V. F. Thomas Company. 847p.
Magee, D.W.; Ahles, H.E. 1999. Flora of the Northeast. Amherst, Massachusetts: University of Massachusetts Press.