Oredezh River near red sandstone cliffs. Siverskaya south from Saint Petersburg, Russia, July 20, 2015
Red sandstone cliff at a bend of Oredezh River. Siverskaya south from Saint Petersburg, Russia, July 20, 2015
Sunken rim-lichen (Lecanora oreinoides) or may be Aspicilia on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Accumulation of fossilized shells in sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Deposits of masses of fossilized sea shells in sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Texture of fossilized sea shells in sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Gorchakovshchina (Gorchakovsky) Waterfall and red sandstone cliffs near Volkhov. Leningrad Region, Russia, August 6, 2016
Close up of yellow cobblestone lichen Acarospora socialis in partial shade on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
View of red sandstone cliffs of Oredezh River. Siverskaya south from Saint Petersburg, Russia, July 20, 2015
Sandstone pillars of Mount Amir from a valley west from Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Red sandstone formations of Nahal Amir wadi, 5 miles north from Eilat. The Middle East, March 25, 2002
Red sandstone cliff facing Oredezh River. Siverskaya south from Saint Petersburg, Russia, July 20, 2015
Sandstone cliff in Maszhabiya (Al Mashabiya) Reserve near Abu Samra. Southern Qatar, April 8, 2016
Red sandstone cliff of Oredezh River in Siverskaya, 50 miles south from Saint Petersburg. Russia, July 13, 2017
Close up of green Cladonia lichen on sandstone or limestone in a forest in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
Carpentry Shop Hill in Ramon Crater, west from the road to Eilat, sandstone which baked and then cooled down and crystallized into prism-like shapes. Mitzpe Ramon, the Middle East, February 1, 2001
Timna Mushroom made from pink sandstone at morning at around 9:00. 13 miles north from Eilat, the Middle East, June 13, 2002
Red sandstone at Gaye Avud near Mount Shehoret, 3 miles north from Eilat. The Middle East, March 14, 2002
Arches in a sandstone hill in western Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Imperfect sandstone mushroom north-west from Timna Mountains. The Middle East, March 15, 2001
Imperfect sandstone mushroom north-west from Timna Mountains. The Middle East, March 15, 2001
Baked sandstone near Lost Pines Trail in Bastrop State Park. Bastrop, Texas, September 15, 2012
Sandstone cliffs and a rocky beach in northern part of Ras Abrouq Peninsula, north from Zekreet. Qatar, June 24, 2016
Eroded sandstone in Ramon Crater. Mitzpe Ramon, the Middle East, February 1, 2001
Upper fragment of a sandstone formation in Timna Mountains. The Middle East, March 15, 2001
Ancient caves in sandstone for mining of copper in western Timna Park, near Eilat. The Middle East, April 25, 2001
Sandstone cliffs of Mount Amir from a passage west from Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Lower fragment of a sandstone formation in Timna Mountains. The Middle East, March 15, 2001
View of a popular tourist area of the sandstone mushroom in Timna Park east from Mount Berekh, 16 miles north from Eilat. The Middle East, February 14, 2002
Red sandstone on steep bank of Oredezh River in Siverskaya, 45 miles south from Saint Petersburg. Russia, August 16, 2018
Young patch of peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrop at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Pattern of yellow cobblestone lichen Acarospora socialis on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Close up of yellow cobblestone lichen Acarospora socialis on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) with apothecia on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
View of multi-colored sandstone from a trail along a western slope of Mount Yoash, 4 miles north-west from Eilat. The Middle East, January 17, 2002
A sandstone pillar at a passage west from Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Duck-like red sandstone erosion below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone along a trail in northern Timna Park. The Middle East, April 25, 2001
Sandstone cliffs of Nahal Gishron creek, a trail 20570 3 miles west from Eilat. The Middle East, January 17, 2002
Sandstone at Cottonwood Creek Dinosaur Trail, 25 miles south-west from Casper. Wyoming, July 27, 2010
Copper oxides in red sandstone of Mount Amir near the site of ancient copper mining, 5 miles north from Eilat. The Middle East, March 25, 2002
Morel-like red sandstone erosion below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone quarry in Jabal Al Jassasiya site, on north-eastern coast. Qatar, December 12, 2015
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Red sandstone at Gaye Avud, 3 miles north from Eilat. The Middle East, March 14, 2002
White sands and sandstone erosions below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone on Geological Trail through Timna Mountains. The Middle East, March 15, 2001
Multicolored sandstone of Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Sandstone cliffs at the foot of Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Sandstone erosion below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone cliffs along Tsafit Creek 10 miles west from Dimona. The Middle East, November 29, 2001
Ancient copper mining cave in sandstone of a small wadi in western Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone erosion below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
White sands and sandstone erosions below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Acacia bush and pink sandstone along Tsafit Creek 10 miles west from Dimona. The Middle East, November 29, 2001
A sandstone canyon west from Mount Amir, 5 miles north from Eilat. The Middle East, March 25, 2002
Lizard-like sandstone formation over Solomon Pillars in Timna Park at morning. 13 miles north from Eilat, the Middle East, June 13, 2002
Sandstone erosion below western cliffs in Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Sandstone formation at Geological Trail in Timna Park at early morning around 6:30. 13 miles north from Eilat, the Middle East, June 13, 2002
Eroded sandstone in western Timna Park, 13 miles north from Eilat. The Middle East, November 7, 2002
Peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrop at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Sandstone bottom of Nahal Gishron creek, a trail 20570 3 miles west from Eilat. The Middle East, January 17, 2002
Sandstone cliffs in northern part of Ras Abrouq Peninsula, north from Zekreet. Qatar, June 24, 2016
Pigtail moss (Weissia controversa) on sandstone on a road at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Red sandstone of Nahal Amir wadi, 5 miles north from Eilat. The Middle East, March 25, 2002
Red sandstone of Griaznovka River springs in Rozhdestveno Village. Gatchina District of Leningrad Region, Russia, January 6, 2016
Red sandstone of Nahal Amir wadi, 5 miles north from Eilat. The Middle East, March 25, 2002
Red sandstone with fossils at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Pink sandstone along Tsafit Creek 10 miles west from Dimona. The Middle East, November 29, 2001
Baked sandstone prisms on a top of "Carpenter Shop" hill on the bottom of Ramon Crater (Makhtesh Ramon). The Middle East, October 3, 2002
Firedot lichen Xanthocarpia crenulatella (Caloplaca crenulatella) (orange) and Acarospora (brown) on sandstone on a bridge in Wolf Pen Creek Park. College Station, Texas, January 13, 2018
Accumulation of fossils in sandstone at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Red sandstone with fossilized sea shells at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Red sandstone with many sea fossils at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Red sandstone with sea fossils at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Red sandstone with fossilized shells at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Accumulation of sea fossils in sandstone at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Accumulation of fossilized shells in sandstone at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Accumulation of various fossilized shells in sandstone at Brazos River near Whiskey Bridge, on Highway 21 west from Bryan. Texas, August 9, 2013
Seablite (Suaeda vermiculata) near sandstone cliffs on Purple Island (Jazirat Bin Ghanim). Al Khor, Qatar, June 18, 2016
Firedot lichen Xanthocarpia crenulatella (Caloplaca crenulatella) (orange), Acarospora (brown), Acarospora or Pleopsideum (yellow) and Lecidea(?)(black) lichens on sandstone rocks of a bridge in Wolf Pen Creek Park. College Station, Texas, January 13, 2018
Lichens on sandstone at the base of the CCC pavilion of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, November 17, 2018
Green Cladonia lichen on sandstone or limestone in a forest in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
Soredia of peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrop at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Old patch of peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrop at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Turbin lichen (Cladonia peziziformis) on side surface of sandstone or limestone rocks near the ground at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrop at the road descent at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Buellia or may be Lecidella lichen on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Black dotted lichen Buellia or may be Lecidella on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa with soredia on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa on sandstone in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa covering sandstone in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Black dots of a lichen Buellia or may be Lecidella on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Yellow cobblestone lichen Acarospora socialis on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) and other lichens on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
White crust of sunken rim-lichen (Lecanora oreinoides) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Pattern of white crust of sunken rim-lichen (Lecanora oreinoides) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Sunken rim-lichen (Lecanora oreinoides) and peppered rock-shield lichen (Xanthoparmelia conspersa) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Dust lichen (Lepraria) in shady spot on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Dust lichen (Lepraria) in shady spot on sandstone in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Buellia or may be Lecidella lichen on sandstone in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Salted shell lichen (Coccocarpia palmicola) on sandstone in shade in an oak forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Rough speckled shield lichen (Punctelia rudecta) on sandstone in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Rosettes of peppered rock-shield lichen (Xanthoparmelia conspersa) on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Green-blue rosette lichen (Physcia) on sandstone in Boonville Cemetery. Bryan, Texas, January 27, 2019
Pyxine lichen on sandstone in Boonville Cemetery. Bryan, Texas, January 27, 2019
Turbin lichen (Cladonia peziziformis) on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 12, 2019
Terrestrial moss Thelia lescurii(?) on sandstone in shade at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 12, 2019
Flat green moss Fissidens, could be F. adianthoides or F. taxifolius, on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 12, 2019
Aspicilia(?) lichen on a sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) with caloplaca on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) with Squamulea squamosa (Caloplaca squamosa) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Aspicilia(?) lichen with Squamulea squamosa (Caloplaca squamosa) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Lichen Diploschistes actinostomus on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Lichen Diploschistes actinostomus on a sandstone bench near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Yellow cobblestone lichen Acarospora socialis in partial shade on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Some grey lichen on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) with soredia on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Apothecia of stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Close up of stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) with Squamulea squamosa (Caloplaca squamosa) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) with Lecanora muralis (Protoparmeliopsis muralis) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Close up of rosette lichen (Physcia) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Yellow cobblestone lichen Acarospora socialis in partial shade on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Texture of yellow cobblestone lichen Acarospora socialis in partial shade on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Patch of rosette lichen (Physcia) with Lecanora muralis (Protoparmeliopsis muralis) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) with Xanthomendoza weberi (Gallowayella weberi) (orange) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) and Xanthomendoza weberi (Gallowayella weberi) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) and bare-bottomed sunburst lichen (Xanthomendoza weberi, Gallowayella weberi) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Patch of stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Peppered rock-shield lichen (Xanthoparmelia conspersa) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Diploschistes actinostomus and stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on a sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Close up of stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Diploschistes actinostomus together with stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on a sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Some dark-brown crustous lichen on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Various lichens on sandstone in Bastrop State Park. Bastrop, Texas, March 14, 2019
Lichen Diploschistes actinostomus(?) on sandstone near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on Caloplaca on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Lichen Diploschistes actinostomus(?) together with Caloplaca on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Aspicilia(?) lichen on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Yellow cobblestone lichen Acarospora socialis on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Rosette lichen (Physcia) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Some grey crustous lichen on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Grey crustous lichen and Caloplaca on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Apothecia of firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, March 14, 2019
Yellow cobblestone lichen Acarospora socialis on sandstone of Fehr s Overlook Shelter in Bastrop State Park. Bastrop, Texas, March 14, 2019
Some whitish crustouse lichen on sandstone of Fehr s Overlook Shelter in Bastrop State Park. Bastrop, Texas, March 14, 2019
Cracked whitish crustous lichen on sandstone of Fehr s Overlook Shelter in Bastrop State Park. Bastrop, Texas, March 14, 2019
Close up of button lichen (Buellia) on sandstone of Fehr s Overlook Shelter in Bastrop State Park. Bastrop, Texas, March 14, 2019
Button lichen (Buellia) on sandstone of Fehr s Overlook Shelter in Bastrop State Park. Bastrop, Texas, March 14, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone outcrops at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, April 19, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone at Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Aspicilia(?) lichen on a sandstone bench near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Red sandstone with fossilized sea shells near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Red sandstone with fossils near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Red sandstone with many sea fossils near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Red sandstone with sea fossils near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Accumulation of various fossilized shells in sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Deposits of fossil sea shells in sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Layer of fossilized sea shells in red sandstone near Whiskey Bridge of Brazos River, on Highway 21 west from Bryan. Texas, November 29, 2019
Peppered rock-shield lichen Xanthoparmelia conspersa on a sandstone outcrop at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 26, 2020
Pattern of a lichen with olive green apothecia on a rock in a forest in area of sandstone outcrops at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 26, 2020
Peppered rock-shield lichen (Xanthoparmelia conspersa) on a sandstone rock at an overlook point in Bastrop State Park. Bastrop, Texas, February 23, 2020
Firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, February 23, 2020
Silvery leaves of oldplainsman (Hymenopappus artemisiifolius) on a sandstone rock at an overlook point in Bastrop State Park. Bastrop, Texas, February 23, 2020
Scaly stippled lichen (Endocarpon pusillum) on a thin layer of soil over exposed sandstone rocks in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2020
Dried scaly stippled lichen (Endocarpon pusillum) with moss on sandstone rocks in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2020
Pepper-like lichen Sarcogyne regularis(?) on a sandstone rock in prairie in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2020
Caloplaca together with a black lichen Endocarpon pusillum on a sandstone rock in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 21, 2020
Red sandstone cliff near Oredezh River. Siverskaya south from Saint Petersburg, Russia, July 20, 2015
Red sandstone near Oredezh River in Siverskaya, 45 miles south from Saint Petersburg. Russia, August 16, 2018
Red sandstone reflected in Oredezh River in Siverskaya, 45 miles south from Saint Petersburg. Russia, August 16, 2018
Orange and grey lichens on sandstone at the base of the CCC pavilion of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, November 17, 2018
Orange lichen on sandstone at the base of the CCC pavilion of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, November 17, 2018
Grey and orange lichens on sandstone at the base of the CCC pavilion of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, November 17, 2018
Various lichens on sandstone at the base of the CCC pavilion of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, November 17, 2018
Chiseled sunken disk lichen (Circinaria contorta, Aspicilia contorta) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Crust of firedot lichen Squamulea squamosa (Caloplaca squamosa) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Texture of sunken rim-lichen (Lecanora oreinoides) on sandstone outcrops in an oak and red cedar forest at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Yellow cobblestone lichen Acarospora socialis on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Soredia of peppered rock-shield lichen (Xanthoparmelia conspersa) on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Small rosette of peppered rock-shield lichen (Xanthoparmelia conspersa) on sandstone at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 25, 2019
Reverchon s false pennyroyal (Hedeoma reverchonii) on sandstone cliffs of Moore s Hill Outcrop at FM Road 3090 2 miles north-east from Navasota. Texas, September 22, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone bench at Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) with caloplaca on sandstone in Bastrop State Park. Bastrop, Texas, October 13, 2019
Faded yellow cobblestone lichen Acarospora socialis on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Yellow cobblestone lichen Acarospora socialis on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Rosette lichen (Physcia) on sandstone of Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Ruffle lichen (Parmotrema) on a sandstone bench near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Lichen Diploschistes actinostomus on a sandstone bench near Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
Texture of stonewall rim-lichen (Lecanora muralis, Protoparmeliopsis muralis) on sandstone bench at Lost Pines Overlook in Bastrop State Park. Bastrop, Texas, October 13, 2019
