Lomatogonium rotatum - (L.) Fries ex Fern.
Marsh Felwort
Other Common Names: marsh felwort
Taxonomic Status: Accepted
Related ITIS Name(s): Lomatogonium rotatum (L.) Fries ex Fern. (TSN 29992)
Unique Identifier: ELEMENT_GLOBAL.2.127992
Element Code: PDGEN0C010
Informal Taxonomy: Plants, Vascular - Flowering Plants - Gentian Family
Kingdom Phylum Class Order Family Genus
Plantae Anthophyta Dicotyledoneae Gentianales Gentianaceae Lomatogonium
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Concept Reference
Concept Reference: Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Concept Reference Code: B94KAR01HQUS
Name Used in Concept Reference: Lomatogonium rotatum
Conservation Status

NatureServe Status

Global Status: G5
Global Status Last Reviewed: 15Jul2016
Global Status Last Changed: 07Jun1984
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Reasons: Widespread and locally abundant circumboreal species, rare at southern edges of range (e.g., Maine).
Nation: United States
National Status: N4N5
Nation: Canada
National Status: N4N5 (07Sep2017)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alaska (SNR), Colorado (S2), Idaho (S1), Maine (S1), Montana (S1S2), New Mexico (SNR), Utah (S1S2), Wyoming (S2)
Canada Alberta (S3), British Columbia (S3), Labrador (S3S4), Manitoba (S2S3), New Brunswick (S1), Newfoundland Island (S2S3), Northwest Territories (SNR), Nunavut (SU), Ontario (S4S5), Quebec (S3S4), Saskatchewan (S3), Yukon Territory (S3)

Other Statuses

NatureServe Global Conservation Status Factors

Range Extent Comments: Greenland to Alaska, south to Colorado.

Number of Occurrences: 6 - 20
Number of Occurrences Comments: No clear estimates of its population level are known. It has been recorded (Table 1) on 8 islands in the Great Wass Island Archipelago plus one island off Schoodic Point (Little Moose Island) (Olday et al. 1982) and on Schoodic Point itself (Stebbins 1928). There are at least three distinct populations on Great Wass Island, three on Outer Sand Island, and five on Inner Water Island. Table 1 gives the names of all current and historic locations for LOMATOGONIUM in Maine. All of these locations have extant populations except for Schoodic Point, and were visited in 1982 (two islands) and 1983 (seven islands).

Overall Threat Impact Comments: Lomatogonium rotatum grows where hikers, beachcombers, and nature lovers are likely to walk. At this time, other threats such as animal predation, loss of habitat through succession, or displacement by other plants do not appear to be important to LOMATOGONIUM on Great Wass Island, Crumple Is. and Mistake Is. (all in ME; TNC owned islands). It is unlikely that these factors are adversely affecting the other known LOMATOGONIUM locations. The population at Schoodic Point, ME, whose status is unknown, would be the most susceptible to trampling or picking as it is (was?) located in a high use area of Acadia National Park.

Other NatureServe Conservation Status Information

Global Range: Greenland to Alaska, south to Colorado.

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map

U.S. & Canada State/Province Distribution
United States AK, CO, ID, ME, MT, NM, UT, WY
Canada AB, BC, LB, MB, NB, NF, NT, NU, ON, QC, SK, YT

Range Map
No map available.

U.S. Distribution by County Help
State County Name (FIPS Code)
ID Clark (16033), Custer (16037), Lemhi (16059)
ME Hancock (23009), Washington (23029)
MT Beaverhead (30001)
WY Albany (56001), Carbon (56007)*, Laramie (56021)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
01 Maine Coastal (01050002)+
10 Red Rock (10020001)+, Upper North Platte (10180002)+*, Upper Laramie (10180010)+, Cache La Poudre (10190007)+, Lone Tree-Owl (10190008)+, Crow (10190009)+
17 Birch (17040216)+, Little Lost (17040217)+, Big Lost (17040218)+, Lemhi (17060204)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
Basic Description: This species is a small annual or biennial herb with an erect, branched or unbranched stem.
General Description: Felwort is a glabrous annual with usually unbranched stems that are 5-15 cm high. The opposite leaves are narrowly oblong to lance-shaped and 1-3 cm long. White or bluish flowers are borne on slender, 1-3 cm long stalks which arise from the axils of the upper leaves. The 5 spreading, lance-shaped petals are 6-15 mm long and are united at the base and subtended by slightly longer, narrow, green sepals. Each petal has 2 small appendages at the base, and there are 5 stamens. The fruit is a many-seeded, egg-shaped capsule that is as long as the petals.
Technical Description: Lomatogonium rotatum has an erect, branched or unbranched stem, 0.3 to 2.5 dm tall, and strongly ascending capillary branches. The leaves are opposite entire, slightly fleshy; the lower ones spatulate and the middle and upper linear-lanceolate, sharp pointed, and 0.4 to 3 cm long. The flowers are borne singly at the tops of branches or the axils of leaves. The sepals number 2-5 and are similar to the median leaves, nearly equalling to much exceeding the corolla. They are conspicuous features both in flower and fruit. The corolla is rotate, porcelain-blue and relatively conspicuous. Each petal is sharp pointed, ranges between 0.5-1.5 cm long, and has at its base pairs of distinctive scale-like, fringed nectar producing appendages.
The stamens are borne on the short corolla tube. The stigmatic surface is decurrent along the sides of the narrowly egg shaped ovary. The fruit is an oblong capsule (0.5 to 1.7 cm) somewhat acute, which contains numerous small seeds. Lomatogonium flowers in Maine from mid-August to late September and early October.

Diagnostic Characteristics: SWERTIA PERENNIS has similar flowers but is a perennial. Annual gentians have tubular rather than star-shaped corollas. This plant is often overlooked because it blooms in August.
Reproduction Comments: Little is known about the reproductive biology of this species. Floristic manuals indicate that this is an annual or biennial. Longer term studies are needed to determine its duration. The pollinators are unknown. Syrphid flies, bumblebees, and several species of butterflies are present in or near their populations, and a syrphid fly was seen visiting LOMATOGONIUM in late September on Water Island (Inner Water Island). It is likely that nectar is the reward for pollinators, although we did not verify the presence of nectar. It appears that this species is reproducing succesfully by seed. Many reproductively mature plants were observed as well as reproductively immature, non-flowering individuals. It is also unknown how the seeds are dispersed. Because of its short stature migratory songbirds, esp. Fringillids, may be involved with seed dispersal and/or seed predation.
Ecology Comments: Lomatogonium rotatum's distribution in Maine is restricted to the moist maritime zone along the coast of eastern Maine (Famous and Campbell 1984). Compared to inland and coastal sections farther west summer temperatures are cooler, the incidence of fog is higher, rainfall and fog-drip rates are higher, and evaporation rates are lower, providing an abundance of water. These conditions are not as extreme when Lomatogonium rotatum is in full bloom in August and September.
Estuarine Habitat(s): Herbaceous wetland
Palustrine Habitat(s): Bog/fen, HERBACEOUS WETLAND
Habitat Comments: The more salient features of the habitat of LOMATOGONIUM ROTATUM include moist soils, full sunlight, minimal competition, and, in eastern North America, close proximity to the sea along outer islands and headlands. Hence it most characteristically grows in thin soils bordering headlands or ledges or in pockets of sandy or gravelly soil. A soil test from Red Head on Great Wass Island, performed by the Maine Soil Testing Lab, indicates circumneutral pH and an excessive level of calcium. It is frequently found in seepage areas between boulders and in turf surrounding temporary and permanent brackish and freshwater pools, and in moist rock crevices. It generally does not colonize crevices close to the breaking surf.


Economic Attributes Not yet assessed
Management Summary
Stewardship Overview: Studies on the distribution and abundance of LOMATOGONIUM ROTATUM in eastern Maine, and its reproductive biology, and demographic studies of populations on selected locations in Maine could be very informative about the factors controlling the distribution and abundance of these species. However, in view of the apparent size and stability of the populations in eastern Maine and low level of threat, stewardship needs are minimal.
Restoration Potential: Not enough is known about germination requirements or the soil needs of seedlings to predict how population size would respond to soil changes associated with human trampling.
Preserve Selection & Design Considerations: The Nature Conservancy might prevent the building of trails to certain parts of Great Wass Island (e.g., the headland located on the southwest corner of the Pond or to Red Head).
Management Requirements: It is our opinion that LOMATOGONIUM ROTATUM occupies vegetationally stable habitats in eastern Maine and that short-term reductions in population size are most likely to result from human activity like trampling and development.
Monitoring Requirements: Before establishing a biological monitoring program, the distribution and abundance of LOMATOGONIUM ROTATUM in Maine needs to be established. Because we doubled the known stations of this species in Maine by visiting 10 islands in the proper season (two of which were known to have LOMATOGONIUM), it is likely that there are many more locations to be discovered in eastern Maine. Most outer islands large enough to support vegetation are good candidates for LOMATOGONIUM.

For known populations, detailed, long-term demographic studies, including all age classes, might be the best monitoring system to show how LOMATOGONIUM ROTATUM population size varies. It would be most efficient to study a limited number of populations chosen to cover some parameters like competition, population size and density, proximity to other LOMATOGONIUM populations, and substrate characteristics.

For specific biological monitoring, we recommend establishing several permanently marked 1x1 m plots within populations of LOMATOGONIUM. Some plots could be in areas subject to trampling and others out of the way of human activity. A yearly count of flowering stems would provide a simple estimate of the status of this taxon.

Monitoring Programs: C.S. Campbell, N.C. Famous, C.D. Richards and B.S. Vickery know the locations of some or all of the extant sites in Maine.
Management Research Needs: (1) What is the abundance and distribution of LOMATOGONIUM in eastern Maine? (2) How large are the effective population units? Are larger populations on larger islands a series of discrete small populations such as is seen on Great Wass Island? (3) How do plants respond to trampling? (4) How narrow is the niche of LOMATOGONIUM ROTATUM or how narrowly adapted is it to limited competition and soil characteristics like pH, aeration, and organic content?
Population/Occurrence Delineation Not yet assessed
Population/Occurrence Viability
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
NatureServe Conservation Status Factors Edition Date: 13Jul1994
NatureServe Conservation Status Factors Author: N.C. FAMOUS, C.S. CAMPBELL, MEFO (1994); rev. L. Morse, 7/95
Management Information Edition Author: N.C. FAMOUS, C.S. CAMPBELL, MEFO
Element Ecology & Life History Edition Date: 13Jul1994

Botanical data developed by NatureServe and its network of natural heritage programs (see Local Programs), The North Carolina Botanical Garden, and other contributors and cooperators (see Sources).

  • Andersen, M.D. and B. Heidel. 2011. HUC-based species range maps. Prepared by Wyoming Natural Diversity Database for use in the pilot WISDOM application operational from inception to yet-to-be-determined date of update of tool.

  • Anderson, J.P. 1959. Flora of Alaska and adjacent parts of Canada. Iowa State University Press, Ames. 543 pp.

  • Campbell, C. S., N. C. Famous, andM. Zuck. Reproductive biology of Primula laurentiana Fernald (Primulceae) in Maine. In prep.

  • Critical Areas Program. 1981. Maine State Planning Office, Augusta, ME.

  • Crow, Garrett E., et al. 1981. Rare and Endangered Vascular Plant Species in New England. New England Botanical Club, Cambridge, Massachusetts. p. 259-299.

  • Dorn, R. D. 1992. Vascular Plants of Wyoming, second edition. Mountain West Publishing, Cheyenne, WY.

  • Dorn, R. D. 2001. Vascular Plants of Wyoming, third edition. Mountain West Publishing, Cheyenne, WY.

  • Douglas, G.W., D. Meidinger, and J. Penny. 2002. Rare Native Vascular Plants of British Columbia, 2nd ed. B.C. Conserv. Data Centre, Terrestrial Inf. Branch, Victoria. 358pp.

  • Douglas, G.W., D. Meidinger, and J. Pojar. eds. 1999. Illustrated Flora of British Columbia, Vol. 3, Dicotyledons (Diapensiaceae through Onagraceae). B.C. Minist. Environ., Lands and Parks, and B.C. Minist. For., Victoria. 423pp.

  • Douglas, G.W., G.B. Straley, and D. Meidinger, eds. 1998. Rare Native Vascular Plants of British Columbia. Conserv. Data Centre, Resour. Inventory Branch, B.C. Minist. Environ., Lands and Parks, Victoria, and B.C. Minist. For., Victoria.

  • Evert, E. F. 2010. Vascular Plants of the Greater Yellowstone Area: Annotated Catalog and Atlas. Park Ridge, IL.

  • Famous, N. C., and C. S. Campbell. 1985. Lomatogonium rotatum. In: The Nature Conservancy Element Stewardship Abstract [Data base]. Boston, MA: The Nature Conservancy, Eastern Regional Office.

  • Famous, N.C. and C.S. Campbell. 1984. Lomatogonium rotatum (Gentianaceae) and Primula laurentiana (Primulaceae) in Maine: New localities and general distributions. Rhodora 86:425-428.

  • Fernald, M. L. 1919. Lomatogonium the correct name for Pleurogyne. Rhodora 21:193-198.

  • Fernald, M. L. 1950. Gray's manual of botany. 8th edition. Corrected printing (1970). D. Van Nostrand Company, New York. 1632 pp.

  • Fertig, W. 2000. State Species Abstract: Lomatogonium rotatum. Wyoming Natural Diversity Database. Available on the internet at www.uwyo.edu/wyndd.

  • Gleason, H.A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Canada. New York Botanical Garden, Bronx, NY.

  • Gleason, H.A., and A. Cronquist. 1963. Manual of vascular plants of northeastern United States and adjacent Canada. D. Van Nostrand Company, New York, NY. 810 pp.

  • Harrington, H. D. 1954. Manual of the Plants of Colorado. Sage Books, Chicago, IL.

  • Heidel, B., J. Handley and M. Arnett. 2013. Status report on sensitive plant species of of Pole Mountain wetlands. Prepared for the Medicine Bow National Forest. Wyoming Natural Diversity Database, Laramie, WY.

  • Herbarium, Department of Botany, University of Manitoba, Winnipeg, Manitoba, Canada.

  • Herbarium, Museum of Man and Nature, 190 Rupert Avenue, Winnipeg, Manitoba.

  • Hitchcock, C. L., A. Cronquist, and M. Ownbey. 1959. Vascular Plants of the Pacific Northwest, Part 4: Ericaceae through Campanulaceae. University of Washington Press, Seattle, WA.

  • Holmgren, N. 1998. Illustrated Companion to Gleason and Cronquist's Manual - Illustrations of the Vascular Plants of Northeastern United States and Adjacent Canada. New York Botanical Garden, Bronx NY.

  • Hulten, E. 1968. Flora of Alaska and Neighboring Territories. Stanford University Press. Palo Alto, CA. 1008 pp.

  • Hulten, E. 1968. Flora of Alaska and neighboring territories. Stanford Univ. Press, Palo Alto, CA. 1008 pp.

  • Hultén, E. 1948. Flora of Alaska and Yukon: VIII:Dicotyledoneae ERICALES, PRIMULALES, CONTORTAE, TUBULFLORAE 1, (POLEMONIACEAE, HYDROPHYLLACEAE). Lund, Sweden. pp. 1203-1341

  • Hultén, E. 1967. Comments on the flora of Alaska and Yukon. Arkiv För Botanik II 7(1):1-147.

  • Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

  • Lesica, P. 1995d. Notes on new additions to Montana flora.

  • Lesica, P. In progress. Notes on new additions to Montana flora.

  • Lesica, P., P. Husby, and S. V. Cooper. 1998. Noteworthy collections: Montana. Madrono 45:328-330.

  • Nelson, A. 1904. Plantae Andrewseae. Proc. of Biol. Soc. Washington 17:173-180.

  • Nelson, B. E. and R. Hartman. 2001. Final report on the general floristic inventory of southeastern Wyoming. Unpublished report prepared for the Bureau of Land Management, Wyoming Office by the Rocky Mountain Herbarium, University of Wyoming, Laramie, WY.

  • Olday, F. C., S. C. Gawler, and B. S. Vickery. 1983. Seven unusual subarctic plants of the Maine coast. A report prepared for the Critical Areas Program. Maine State Planning Office. 66 pp.

  • Pike, R. B. 1983. Note on Lomatogonium. Rhodora 65:364-365.

  • Pike, R. B. and A. R. Hodgdon. 1963. The flora of the Wolf Islands, New Brunswick. Rhodora 65:92-96.

  • Porsild, A.E. 1951. Botany of southeastern Yukon adjacent to the Canol Road. National Museum of Canada Bulletin No. 121. Canada Department of Resources and Development, Ottawa. 400pp.

  • Porsild, A.E. 1955. The vascular plants of the Western Canadian Arctic Archipelago. National Museum of Canada, Bulletin No.135. Canada Department of Northern Affairs and National Resources. pp. 69,174 & 175.

  • Porsild, A.E. and W.J. Cody. 1980. Vascular Plants of Continental Northwest Territories, Canada. National Museums of Canada, Ottawa.

  • Scoggan, H.J. 1978. The Flora of Canada. National Museum of Natural Sciences, National Museum of Canada, Publ. in Botany 7(4).

  • Stebbins, G. L. 1929. Lomatogonium (L.) Fries. in Maine. Rhodora 31:143.

  • Welp, L., W.F. Fertig, G.P. Jones, G.P. Beauvais, and S.M. Ogle. 2000. Fine filter analysis of the Bighorn, Medicine Bow, and Shoshone National Forests in Wyoming. Wyoming Natural Diversity Database, Laramie, WY.

  • Welsh, S. L., N. D. Atwood, S. Goodrich, and L. C. Higgins [eds]. 1993. A Utah Flora (2nd ed., revised). Provo, UT: Brigham Young University. 986 pp.

  • White, D.J. and K.L. Johnson. 1980. The Rare Vascular Plants of Manitoba. National Museums of Canada Syllogeus no. 27.

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