Coast creeping moss

Conardia compacta (C. Mull.) Robins.

Condardia compacta
Russ Kleinman, Karen Blisard

State Protection
Not Listed
Not listed or protected by New York State.
Federal Protection
Not Listed
State Conservation Status Rank
Critically Imperiled in New York - Especially vulnerable to disappearing from New York due to extreme rarity or other factors; typically 5 or fewer populations or locations in New York, very few individuals, very restricted range, very few remaining acres (or miles of stream), and/or very steep declines.
Global Conservation Status Rank
Secure globally - Common in the world; widespread and abundant (but may be rare in some parts of its range).


Did you know?

This moss has been put under various genera over time including Amblystegium, Rhynchostegiella, Hypnum, and Stereodon. The genus was named by Harold Robinson of the Smithsonian Institution to honor Henry Shoemaker Conard, a noted bryologist and environmental preservationist from Pennsylvania and later Grinnell College in Iowa (Robinson 1976). Dr. Conard was the author of the widely used book "How to Know the Mosses and Liverworts" (Wikipedia contributors).

State Ranking Justification

The rank was confirmed to be S1 based on Cleavitt et al.'s (2006) report. Three specimens were verified. The last collection was made in 2005.

Short-term Trends

The short term trend appears stable three sites have been verified as extant and sampled in 2005. 

Long-term Trends

The long term trend may be stable, three extant sites have been relatively recently surveyed. Resurveys are needed to confirm this trend. 

Conservation and Management


Over collection and human disturbance at sites accessible to visitation are the primary threats.

Conservation Strategies and Management Practices

Monitor the populations for impacts from human disturbance and collecting. Control any invasive exotic plants infesting the cliff-faces where this moss occurs. 

Research Needs

No reserach needs have been identified.



In New York, this moss has been found on a seepy north facing talus slope, on calcareous cliffs of a gorge trail, and on calcareous outcrops beside a river (New York Natural Heritage Program 2015). Damp cliffs, limestone, swamps, stumps, humus, bark at the base of trees (FNA 2014).

Associated Ecological Communities

  • Calcareous cliff community (guide)
    A community that occurs on vertical exposures of resistant, calcareous bedrock (such as limestone or dolomite) or consolidated material; these cliffs often include ledges and small areas of talus.
  • Calcareous shoreline outcrop (guide)
    A community that occurs along the shores of lakes and streams on outcrops of calcareous rocks such as limestone and dolomite. The vegetation is sparse; most plants are rooted in rock crevices.
  • Shale cliff and talus community (guide)
    A community that occurs on nearly vertical exposures of shale bedrock and includes ledges and small areas of talus. Talus areas are composed of small fragments that are unstable and steeply sloping; the unstable nature of the shale results in uneven slopes and many rock crevices.

Associated Species

  • Amblystegium varium
  • Anomodon spp.
  • Atrichum oerstedianum
  • Brachythecium oxycladon
  • Brachythecium velutinum
  • Bryhnia graminicolor
  • Bryoerythrophyllum recurvirostre
  • Bryum flaccidum
  • Campylium chrysophyllum
  • Didymodon ferrugineus
  • Encalypta procera
  • Hygroamblystegium tenax
  • Hypnum lindbergii
  • Leptodictyum riparium
  • Metzgeria conjugata
  • Mnium marginatum
  • Mnium thomsonii
  • Myurella sibirica
  • Plagiochila porelloides
  • Plagiomnium cuspidatum
  • Plagiomnium rostratum
  • Plagiothecium cavifolium
  • Radula complanata
  • Taxiphyllum deplanatum
  • Tortella tortuosa
  • Tortula mucronifolia


New York State Distribution

New York is along the eastern edge of this species' range in North America. This moss has been collected in central and western New York at three locations in Tompkins and Wyoming counties.

Global Distribution

This moss is distributed widely in the Northern Hemisphere including northern and central Europe, Iceland and Kashmir in Asia. In North America it has been found in Guatemala, in all the Canadian Provinces except New Brunswick and Prince Edward Island. It occurs widely in the western and northern continental United States from New Mexico to California and Utah, east through the plains, Iowa and Texas, the northern rockies, spannig the northern Great Lakes states to Pennsylvania and New York, and south to Missouri, Arkansas, West Virginia and Virginia.

Identification Comments

Identifying Characteristics

Conardia compacta is a small (ocassionally minute), very slender and irregularly branched moss, with narrow leaves that are spearhead- to broadly spearhead-shaped. Its stems are erect ascending or creeping and form soft, thin mats. The stem bases and branch buds have clusters resembling tiny filaments or leaf-like structures. The leaves are 0.6 to 1.2 mm long, typically crowded and have a long, slender tip which is variously curved or spreading, sometimes in different directions, often giving patches a rather crinkly appearance. The thickened leaf midrib (costa) bears minute, cylindric, solid vegetative propagules (gemmae) or slender filaments (rhizoid) on its outer (abaxial) surface. Aside from the midrib the leaf cells are 5 to 9 times longer than wide, but become shorter and broader (square or rectangular) in the alar region (area controling the leaf orientation in response to changes in moisture) of the leaf base On dry specimans the leaves often all point in the same direction (homoallous). The midrib (costa) extends nearly to the leaf tip, but this is not easy to see in the field because the plants are so small. The mouth of the spore case (capsule) has 1 to 2 rows of enlarged specialized elastic separating cells. Inside the mouth the outer row(s) of the teeth are lanceolate, brownish yellow, with either net-veined, net-veined and marked with fine, longitudinal lines or ridges, or with portions bearing delicate lines or ridges at their base and usually forked towards their tip. The inner row of teeth bear typically 1 to 2 cilia, which are half as long as the segments they alternate with. The capsule lid (operculum) is conicial to short beaked. The spores are covered with fine nipple-shaped projections (papillose). When it is present a particularly useful character to distinguish C. compacta is the growth of rhizoids from the back of the midrib. Pale, elongated gemmae sometimes grow from the back of the leaf tip, but these are rarely detectable in the field. (BFNA 2010)

Best Life Stage for Proper Identification

Positive identification of Conardia compacta requires only a small amount of the gametophyte (vegetative) plant that includes the stem, stem base and stem leaves.

Similar Species

Conardia has the appearance of a small Amblystegium species moss, but can be distinguished from this and other similar species by its warty-rough bumped (papillose), much branched, slender filaments (rhizoids) that are frequently inserted on the back of the midrib (costa) or near the leaf apex. Rhizoids can mostly be found in the basal portions of at least some shoots. In addition, the upper (distal) parts of the axillary hairs consist of 1 to 4 cells that are shorter and broader rather than the 1--2 narrow and delicate ones found in Amblystegium. The capsule is only slightly bent in a bow like curve (arcuate) rather than curved throughout as in Amblystegium species. (BFNA 2010)

Best Time to See

The gametophyte (vegetative) form of this moss may be seen throughout the year. No information was found of the timing of capsule maturation.

  • Vegetative

The time of year you would expect to find Coast creeping moss vegetative in New York.

Coast creeping moss Images


Coast creeping moss
Conardia compacta (C. Mull.) Robins.

  • Kingdom Plantae
    • Phylum Bryophyta
      • Class Bryopsida
        • Order Hypnales
          • Family Amblystegiaceae

Additional Resources

Best Identification Reference

Flora of North America Editorial Center for Bryophytes. 2010. Conardia. In: Bryophyte Flora of North America volume 2: Acrocarpous Mosses, Part 2, and Pleurocarpous Mosses (= Flora of North America Vol. 28). Online. Available: (Accessed 2013).

Other References

Cleavitt, N.L., S.A. Williams, and N. Slack. 2006. Updating the rare moss list for New York State: Ecological community and species-centered approaches. Final report for the Biodiversity Research Institute. New York State Museum. Albany, NY.

Crum, H. 2004. Mosses of the Great Lakes Forest, 4th Edition. The University of Michigan Herbarium, Ann Arbor, Michigan. 592 pp.

Ireland, R.R. 1982. Moss flora of the Maritime Provinces. National Museums of Canada, Publications in Botany 13.

New York Natural Heritage Program. 2024. New York Natural Heritage Program Databases. Albany, NY.


About This Guide

This guide was authored by: Aissa Feldmann, Elizabeth Spencer, Steve Young

Information for this guide was last updated on: January 8, 2016

Please cite this page as:
New York Natural Heritage Program. 2024. Online Conservation Guide for Conardia compacta. Available from: Accessed April 16, 2024.