Wayne's Word Index Noteworthy Plants Trivia Lemnaceae Biology 101 Botany Scenic Wildflowers Trains Spiders & Insects Search Bryophyte Photos    Major Botanical Divisions     5 Kingdoms Of Life     Amazing Hornworts  Division Bryophyta (Bryophytes): Nonvascular Embryophytes A liverwort (probably Asterella) in southern California. The lobed, dorsi-ventrally flattened thallus (nonvascular plant body) grows flat on moist soil. The upright, palm-like stalks are archegoniophores (female reproductive structures) and bear young spore-bearing capsules (sporophytes) on their undersides. Liverworts Of The Genus Asterella A liverwort (probably Asterella) in southern California. The lobed, dorsi-ventrally flattened thallus (nonvascular plant body) grows flat on moist soil. The upright, palm-like stalks are archegoniophores (female reproductive structures) and bear young spore-bearing capsules on their undersides. A small mushroom emerging from a clump of mosses and liverworts (probably Asterella) on a shady, moist bank in the chaparral of southern California. The upright structures on the liverworts are archegoniophores (female reproductive structures) bearing young spore-bearing capsules on their undersides. Asterella palmeri in San Mateo Canyon, Santa Ana Mtns. Photo by Dr. W. Jürgen Schrenk. Asterella near the summit of Owens Peak north of Palomar College. Possibly A. palmeri with mature archegoniophores bearing spore-bearing capsules (sporophytes) on their undersides. Liverworts Of The Genus Marchantia Miniature forest of palm-like, female Marchantia archegoniophores. Ontario, Canada. Left: A liverwort (Marchantia) growing in a wet meadow on Palomar Mountain. The upper surface of the gametophyte thallus bears small cups containing asexual buds called gemmae. Right: A magnified view of a gemmae cup showing numerous lens-shaped gemmae inside. Raindrops may splash the gemmae up to three feet (1 meter) away. Each gemma is capable of growing into a new thallus. Note the conspicuous rimmed pores on the upper side of the thallus. Each pore leads into an air chamber containing columns of photosynthetic cells and facilitates in gas exchange. Unlike the stomata of vascular plants which close in dry weather, the air pores of liverworts remain open all the time. Liverworts cannot control their water loss (transpiration) through the pores. They must live in shady, moist areas where they can imbibe water, and where there is sufficient water for their swimming sperm to reach the egg. Marchantia at Los Angeles County Arboretum Marchantia sp. (possibly M. polymorpha) at the Los Angeles County Arboretum. The upper surface of gametophyte thallus bears three small cups containing asexual buds called gemmae. Marchantia sp. (possibly M. polymorpha) at the Los Angeles County Arboretum. The structures resembling miniature palms on male thalli are antheridiophores. They produce swimming sperm that are carried by water to archegoniophores on female thalli. A Liverwort In Creek Near The Walker River Liverwort in a creek near the Walker River north of Bridgeport. It resembles on-line images of the thalloid liverwort Conocephalum conicum. It has a well-marked hexagonal surface on the upper thallus. In the center of each hexagon is a minute pore. These features are barely visible in the above image. The plant was growing in shallow water of a marsh along a slow moving creek with dense population of Lemna trisulca. Lemna trisulca (lower) and liverwort resembling Conocephalum or Marchantia. Dense colonies of these plants were growing intermixed in the shallow water of a marsh along a creek near the Walker River (north of Bridgeport). Highly magnified view of polygonal surface on the upper (dorsal) side of liverwort thallus. The polygons delineate the internal air chambers. In the center of each polygon is a rimmed pore. Each pore leads into an air chamber containing columns of photosynthetic cells and facilitates in gas exchange. Unlike the stomata of vascular plants which close in dry weather, the air pores of liverworts remain open all the time. Liverworts cannot control their water loss (transpiration) through the pores. They must live in shady, moist areas where they can imbibe water, and where there is sufficient water for their swimming sperm to reach the egg. Magnification 400x. Close-up view of liverwort thallus. Minute disklike gemma cup; however, Conocephalum does not produce gemmae according to liverwort references. Could it be an aquatic Marchantia? Image taken with Nikon 1:1 macro lens. Close-up view of limestone block at the Maya pyramid of Tikal in Guatemala showing bright green patch of liverworts surrounded by a dark mass of cyanobacteria (Scytonema). The miniature, palm-like stalks on the liverworts are female reproductive structures called archegoniophores. There are probably some male antheridiophores mixed in with this dense population. Aquatic Liverwors Riccia and Ricciocarpus An aquatic liverwort (Ricciocarpus natans). The lobed, dorsi-ventrally flattened thallus (nonvascular plant body) floats on the surface of quiet streams and ponds. The numerous smaller plants are duckweeds (Lemna minuta), a flowering plant. The duckweed (Lemna turionifera) and two nonvascular aquatic liverworts (Ricciocarpus natans & Riccia fluitans) in Flat Creek, Wyoming. Ricciocarpus natans has a lobed, dorsi-ventrally flattened thallus bearing numerous elongate scales on the underside. This liverwort floats on the surface of quiet streams and ponds. Riccia fluitans has a dichotomously branched thallus forming interconnected chains. The elongated lobes are only about one millimeter wide. Massive submersed colonies of this minute plant are a haven for small aquatic insect larvae. The duckweed (Lemna turionifera) and two nonvascular aquatic liverworts (Ricciocarpus natans & Riccia fluitans) in Flat Creek, Wyoming. Ricciocarpus natans has a lobed, dorsi-ventrally flattened thallus bearing numerous elongate scales on the underside. This liverwort floats on the surface of quiet streams and ponds. Riccia fluitans has a dichotomously branched thallus forming interconnected chains. The elongated lobes are only about one millimeter wide. Massive submersed colonies of this minute plant are a haven for small aquatic insect larvae.   Desert Liverworts Forming Cryptobiotic Crust   True Mosses Moss covered tree trunks in the Coast Range of central Oregon. A true moss showing the leafy, haploid gametophytes (lower portion) and upright stalks with spore-bearing sporangia (capsules) at their tips. The stalks and sporangia constitute the diploid sporophyte. An aquatic moss (Fontinalis) growing in Santa Ysabel Creek in San Diego County, California. This unusual moss grows completely submersed in fresh water. The photo also shows the water fern (Azolla filiculoides) at the lower left and several small duckweeds (Lemna minuta). There is also an aquatic liverwort (Ricciocarpus natans) floating at the lower middle of photo. Left: A white fungus colony resembling a Greek letter growing on wet green moss. The colony is about one inch (2.5 cm) in diameter. Right: Magnified view of the fungus (200x) showing silvery-white hyphae bearing stalked mitosporangia. Each mitosporangium bears many mitospores. These fungi are sometimes called "pin molds" because of the resemblance of the stalked mitosporangia to round-headed pins. They belong to the family Mucoraceae in the fungal division Zygomycota. 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