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41-968: The region contains the Paraguana xeric scrub ecoregion. The coastal plain contains Venezuela's only desert, the Médanos de Coro (the Coro Dunes), on the Paraguaná Peninsula . The Coro region is one of the ten geographical regions into which Venezuela can be divided. Because the two major depression valleys are the Falcón and the Lara, the mountains are sometimes called the Falcón-Lara ranges. The geographic region covers all of Falcón State , half of Lara State and Yaracuy State , and small percentages of Zulia State and Carabobo State . It's

82-534: A talus -bordered residual known as a castle koppie appears. By this association various inselberg fields in Africa and South America are assumed to be the vestiges of eroded etchplains . Clusters of inselbergs, called inselberg fields and inselberg plains, occur in various parts of the world, including Tanzania , the Anti-Atlas of Morocco , Northeast Brazil , Namibia , the interior of Angola , and

123-838: A broader geography and range of rock features, leading to confusion about the precise definition of the term. In a 1973 study examining the use of the term, one researcher found that the term had been used for features in savannah climates 40% of the time, arid or semi-arid climates 32% of the time, humid-subtropical and arctic 12% of the time, and 6% each in humid-tropical and Mediterranean climates. A 1972 paper defined inselbergs as "steep-sided isolated hills rising relatively abruptly above gently sloping ground". This definition includes such features as buttes ; conical hills with rectilinear sides typically found in arid regions; regolith -covered concave-convex hills; rock crests over regolith slopes; rock domes with near vertical sides; tors (koppies) formed of large boulders but with solid rock cores. Thus,

164-571: A complex mosaic of habitats. The coastal grasslands include halophyte plants in salty depressions and dune vegetation that grows along narrow strips of stabilized dunes on the peninsula between Coro and Adícora , and along the mainland coast on either side of Coro. Other areas of mobile dunes have little or no vegetation. Halophyte grasslands are typically low and open, without trees or bushes. Species include Atriplex pentandra , Heterostachya ritteriana , Salicornia fruticosa , Batis maritima and Sesuvium portulacastrum . Grasslands on

205-494: A few freshwater marshes, which hold endemic plant species and provide resting areas for resident and migratory birds. Plants species in the marshes include Acrostichium aurem , Marsilea ancylopoda , Nephrolepis hirsutula , Pitygramma trifoliata , Eichhornia crassipes , Amoreuxia wrightii , Ipomoea wrightiii , Pluchea odorata , Pluchea sagittalia and Eleocharis mutata . The Galapagos carpet weed ( Sesuvium edmonstonei ), formerly thought to be found only on

246-856: A rare bush 1–3 metres (3 ft 3 in – 9 ft 10 in) high, has only been recorded in the Morrocoy National Park in Paraguaná and the Lara-Falcón dry forests ecoregion. The endangered Guajira mouse opossum ( Marmosa xerophila ) has been recorded in some places in Falcón. The species is found only in dry areas in Colombia and Venezuela around the mouth of Lake Maracaibo, mostly tropical thorn or very dry forest with mean temperatures above 24 °C (75 °F) and rainfall from 250–500 millimetres (9.8–19.7 in). Much of its habitat has been converted to agriculture, and

287-458: A similar formation of granite is known as a koppie , an Afrikaans word ("little head") from the Dutch diminutive word kopje . If the inselberg is dome-shaped and formed from granite or gneiss , it can also be called a bornhardt , though not all bornhardts are inselbergs. An inselberg results when a body of rock resistant to erosion, such as granite, occurring within a body of softer rocks,

328-866: A transitional habitat between dry forests and briars. They contain trees under 5 metres (16 ft) high and bushy plants. The low and even storey is mainly composed of Opuntia caracasana , Lippia origanoides and Croton flavens . Many annual plants spring up in the rainy season. The most common species include Croton heliaster , Borreria cumanensis , Caesalpinia mollis , Randia gaumeri , Jacquinia aristata , Caesalpinia coriaria , Pithecellobium dulce , Capparis odoratissima , Capparis linearis , Caesalpinia coriaria , Pereskia guamacho , Prosopis juliflora , Stenocereus griseus , Malpighia species, Bursera tomentosa and Morisonia americana . The scrub contains low bushy plants from 3–8 metres (9.8–26.2 ft) high, mostly very dense, and may be seen as degraded deciduous forests. Many of

369-435: Is almost extinct in Paraguaná due to destruction of its arid habitat in Falcón. Other endangered birds include the plain-flanked rail ( Rallus wetmorei ). The World Wildlife Fund gives the ecoregion the status of "Critical/Endangered". Protected areas in or near to the ecoregion include the 9,128 hectares (22,560 acres) Médanos de Coro National Park , the 1,900 hectares (4,700 acres) Cerro Santa Ana Natural Monument and

410-416: Is exposed by differential erosion and lowering of the surrounding landscape. The word inselberg is a loan word from German , and means "island mountain". The term was coined in 1900 by geologist Wilhelm Bornhardt (1864–1946) to describe the abundance of such features found in eastern Africa . At that time, the term applied only to arid landscape features. However, it has since been used to describe

451-518: Is in the neotropical realm, in the deserts and xeric shrublands biome. The flora and fauna are adapted to extreme conditions of drought, salty soils, high winds and heat. Vegetation includes stunted scrub, low trees and cactuses . Herbaceous or bushy vegetation grows on the dunes and saline depressions by the coast. Further inland there is brush, scrub and areas of briars or cacti. These forms of vegetation may contain differing quantities of deciduous and evergreen trees depending on conditions, forming

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492-463: Is left behind as an isolated mountain. The strength of the uneroded rock is often attributed to the tightness of its jointing . Inselbergs can be reshaped by ice sheets much the same way as roches moutonnées . In northern Sweden , examples of this type of inselberg are called flyggbergs . The inselbergs of Eastern Africa tend to be a refuge for life in the Serengeti of Tanzania and in

533-538: Is some mining in the higher mountains and fishing on the coast. Paraguana xeric scrub The Paraguana xeric scrub (NT1313) is an ecoregion in Venezuela to the north and east of Lake Maracaibo and along the coast of Aruba, Bonaire, and Curaçao . The region holds flora and fauna adapted to the very dry conditions of the coastal dunes and inland areas of bush, scrub, briars and cacti. There are several endangered species of animals and birds. Efforts at protecting

574-437: Is used to describe a mountain that rises from an area of relatively flat and/or lower terrain. For instance, Mount Monadnock rises 610 metres (2,000 ft) above its surrounding terrain and stands, at 965 m (3,165 ft), nearly 300 m (1,000 ft) higher than any mountain peak within 48 km (30 mi). Inselbergs are common in eroded and weathered shields . The presence of an inselberg typically indicates

615-628: The Galápagos Islands , has been observed on a protected strip of shore grasses and bush between Coro and La Vela. However, the description of the specimens is somewhat different from that of the Galapagos species, so it may be a different species. The rare Oxycarpha suaedifolia and Atriplex oestophora are mostly confined to the state of Falcón. Oxycarpha suaedifolia was first reported in 1917, growing in sand dune valleys near La Vela de Coro. Crossopetalum rhacoma (maidenberry),

656-900: The Köppen climate classification is "BSh": arid, steppe, hot arid. Mean monthly temperatures at this location range from 24.4 °C (75.9 °F) in January to 26.8 °C (80.2 °F) in August–September. Yearly total rainfall is about 680 millimetres (27 in). Monthly rainfall is 9.7 millimetres (0.38 in) in February, rising to 74.3 millimetres (2.93 in) in May, falling to 33.3 millimetres (1.31 in) in July and rising again to 141.9 millimetres (5.59 in) in October. The ecoregion

697-765: The Maracaibo dry forests ecoregion. In the south it meets the northeastern section of the Venezuelan Andes montane forests . The southeastern extreme of the ecoregion connects to the La Costa xeric shrublands . The ecosystem includes the valleys of the Lara – Falcón depression in the coastal plains north of the foothills of the Venezuelan Andes , and the Paraguaná Peninsula. In the Pliocene epoch

738-779: The Tocuyo River , arguably the most important river in the area draining 223.44 square kilometres, and emptying into the Caribbean near the Triste Gulf. The Tocuyo river crosses the ecoregion called the Lara Falcón Dry Forest. In the valleys of the Lara-Falcón depression, the Turbio river is the most important due to its volume of water; its mouth is near the Orinoco River basin. With the exception of

779-527: The 3rd largest natural region in the country, covering 5.75% of Venezuela. Coro region is very dry, with the evaporation rate frequently exceeding the precipitation rate at the lower elevations. There are three major river systems in the region. The Pedregal and Paraíso rivers which feed into the Mitare River which empties into the Coro Gulf . The Morere, Barigua and Bucares rivers which together form

820-484: The 7,275 hectares (17,980 acres) León Hill Natural Monument . The Médanos de Coro National Park theoretically protects a sizeable part of the ecoregion, but in practice has often been invaded by individuals and government agencies. There is a municipal dump in the park, privately owned facilities for extracting salt and outlets for untreated waste water. Unplanned housing and tourist facilities have invaded many areas and large areas of scrubland have been destroyed, causing

861-596: The Andes and the Venezuelan Coastal Range . The soils are high in salt, mainly calcite . Soils are sandy along the coast and sandy with clay content further inland. The soils are all low in organic matter and phosphorus, and have pH close to neutral. The Paraguaná peninsula has only intermittent streams. On the mainland the Mitare River divides into the Pedregal and Paraíso rivers, which empty into

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902-599: The Siquisique highlands (which are an igneous remnant of Jurassic age), the rocks are Cenozoic, mostly 30 to 70 m.y.o., (Paleocene, Eocene, Oligocene), overlaid by some Pleistocene and Holocene alluvial deposits. This corresponds well with the Andean orogeny . There are some oil deposits, but mainly the population relies on subsistence farming with some cattle grazing. The dry climate is not conducive to commercial agriculture, but there are some aloe vera plantations. There

943-407: The development of inselbergs have been advanced, refuted and reiterated over a period of more than seventy years." Volcanic or other processes, such as a meteor crater , may give rise to a body of rock resistant to erosion , inside a body of softer rock such as limestone , which is more susceptible to erosion. When the less resistant rock is eroded away to form a plain , the more resistant rock

984-453: The dunes to move and become barren of all vegetation. Attempts have been made to open a tourist complex in the area, destroying large areas of typical vegetation. Marshes have been drained for housing development. Most of the trees have been cut down, often surreptitiously by poor residents, leaving only a few remnants of forest. The wood is used for small buildings, furniture, fencing and fuel. Extensive grazing of livestock such as goats threaten

1025-459: The east of the mouth of Lake Maracaibo and includes the Paraguaná Peninsula . A belt of the xeric scrub extends inland to the foothills of the Venezuelan Andes to the west of Barquisimeto . Along the Caribbean coast there are stretches of Amazon-Orinoco-Southern Caribbean mangroves . To the east the ecoregion merges into the Lara-Falcón dry forests ecoregion, and to the west merges into

1066-517: The environment have been ineffective. Most of the original trees have been cut down, dunes are being destabilized by loss of vegetation, scrub is replaced by farmland and vegetation is destroyed by grazing goats. The Paraguana xeric scrub is in the northwest of Venezuela. It has an area of 1,605,792 hectares (3,968,000 acres). It extends along the Caribbean coast of the ABC islands (Leeward Antilles) to

1107-403: The existence of a nearby plateau or highland, or their remnants. This is especially the case for inselbergs composed of sedimentary rock , which will display the same stratigraphic units as this nearby plateau. However once exposed, the inselbergs are destroyed by marginal collapse of joint blocks and exfoliation sheets . This process leaves behind tors perched at their summits and, over time,

1148-508: The foothills of the Andes. Ground-level temperatures may rise to 50 °C (122 °F) in the sun, but may fall to as low as 15 °C (59 °F) in the shade. The cause of the arid or semi-arid climate is unclear, but may be caused in part by the strong northeast trade winds blowing along the coast and by the contrast in thermal properties between the sea and the land. At a sample location at coordinates 10°45′N 70°15′W  /  10.75°N 70.25°W  / 10.75; -70.25

1189-679: The gulf of Coro. The Tocuyo River , which crosses the Lara–Falcón dry forest ecoregion, is formed by the confluence of the Morere, Barigua and Bucares rivers. It empties into the Caribbean near the Triste Gulf. The Turbio River is the largest in the Lara Falcón depression. Annual rainfall on the Paraguaná Peninsula is usually less than 300 millimetres (12 in), while in the Lara–Falcón valleys it ranges from 350 millimetres (14 in) in dry areas to as much as 1,000 millimetres (39 in) in

1230-469: The habitat. Large areas of scrub have been cleared and replaced by vegetable farms. Small mammals are poached. Other threats come from dam construction, oil exploitation, mining and road building. Inselberg An inselberg or monadnock ( / m ə ˈ n æ d n ɒ k / mə- NAD -nok ) is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain . In Southern Africa ,

1271-682: The higher levels of the peninsula is very different from the rest of the ecoregion. The forests are dense, with two stories of low to medium trees and a thick understory. Common species include Protium tovarense , Tetrochidium rubrivenium , Hieronyma moritziana , Aichomea triplinervia , Qualea calophylla , Laplacea fruticosa , Graffenrieda latifolia , Clusia multiflora , Didymopanax glabratum , Ladenbergia moritziana , Vasconcellea microcarpa , Chamaedorea species, Geonoma species and Wettinia praemorsa . Endemic species include Geonoma paraguanensis , Philodendrum holtonianum and Rodospatha falconensis . There are

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1312-545: The mainland was formed about 3,000 years ago by tectonic uplift. A 32 kilometres (20 mi) long ledge of exposed beach rock protects the eastern shore from strong wave action. The shoreline mainly consists of sandy or sand and silt beaches, with murky waters. Dunes have formed recently from sand that continues to arrive from the Gulf of Venezuela . The valleys of the Lara–Falcón depression contains ancient Quaternary rocks and recent sediments, and include plains and hills between

1353-485: The northern portions of Finland and Sweden . The classification of Anthony Young (1969) distinguishes six types of inselbergs; buttes , conical hills , convex-concave hills, rock crest over regolith-covered slope, rock dome (sugarloaf) and kopje or tor . The types of rock of which inselbergs are made include granite , gneiss and gabbro . Summarizing the understanding on the origin of inselbergs in 1974, geomorphologist Michael Thomas writes "Hypotheses for

1394-467: The peninsula includes thorny plants at elevations of 0–300 metres (0–984 ft), deciduous forests at 300–550 metres (980–1,800 ft), cloud forests at 550–700 metres (1,800–2,300 ft), scrubland with small bush-like trees at 700–800 metres (2,300–2,600 ft) and páramo -like vegetation with dwarf woody plants at 800–830 metres (2,620–2,720 ft) on the Cerro Santa Ana. The flora at

1435-411: The peninsula was an island Paraguana has four marine terraces at 6 metres (20 ft), 15–20 metres (49–66 ft), 40–50 metres (130–160 ft) and 80 metres (260 ft) surrounding the Cerro Santa Ana inselberg . The 830 metres (2,720 ft) Cerro Santa Ana is the highest point in the hills of the center of the former island. The long, narrow and low Médanos Isthmus that joins Paraguana to

1476-402: The population of the species was declining quickly due to trapping for sale as a cage bird, and the population was severely fragmented. It is observed at elevations from 100–1,500 metres (330–4,920 ft), moving seasonally and daily from moist evergreen forest to dry deciduous woodlands, and the surrounding shrubby grasslands and pastures. The yellow-shouldered amazon ( Amazona barbadensis )

1517-557: The remnants are very fragmented. The main breeding period in the Paraguaná Peninsula is the dry season in June and July. It may occur in the Cerro Santa Ana Natural Monument but has not been recorded there. Other vulnerable species found in the more wooded areas are ocelot ( Leopardus pardalis ), cougar ( Puma concolor ) and jaguar ( Panthera onca ). A poison-arrow frog species, Mannophryne lamarcai ,

1558-760: The sand dunes include dense but uneven herbaceous-bushy flora. Species include Scaevola plumieri , Portulaca pilosa , Cakile lanceolata , Cyperus planifolius , Sporobolus virginicus , Sporobolus piramydatus , Ipomoea pes-caprae , Euphorbia buxifolia , Spartina patens , Lycium bridgesii , Calotropis procera , Egletes prostrata , Argusia gnaphalodes , Tournefortia volubilis , Opuntia caracasana , Heterostachys ritteriana , Chamaesyce dioica , Chamaesyce mesembryanthemifolia , Croton punctatus , Cenchrus echinatus and Tribulus zeyheri . Isolated dunes may hold windblown trees and bushes such as Conocarpus erectus , Prosopis juliflora and Vachellia tortuosa . The bush lands are

1599-1013: The species have thorns, spines, and prickles . Common species include Prosopis juliflora , Castela erecta , Stenocereus griseus , Opuntia caracasana , Croton crassifolius , Ipomoea carnea , and Parkinsonia praecox . The driest parts of the arid and semi-arid areas hold dense or sparse vegetation of stunted thorny bushes and cacti. The areas where cacti columns are most common are called cardonales . Common bush species include Castela erecta , Prosopis juliflora , Parkinsonia praecox , Bourreria cumanensis , Pithecellobium dulce , Vachellia tortuosa , Acacia flexuosa , Stenocereus griseus , Opuntia caribea , Ipomoea carnea , Croton heliotropiifolius , Ipomoea carnea , Indigofera suffruticosa , Tephrosia senna , Aristida venezuelae , Calotropis procera and Capraria biflora . Common cacti include Acanthocereus tetragonus , Cereus hexagonus , Opuntia elatior and Pilosocereus lanuginosus . The vegetation of

1640-568: The terms monadnock and inselberg may not perfectly match, though some authors have explicitly argued these terms are completely synonymous. Monadnock is derived from an Abenaki term for an isolated hill or a lone mountain that stands above the surrounding area, typically by surviving erosion. Geologists took the name from Mount Monadnock in southwestern New Hampshire . It is thought to derive from either menonadenak ( transl.  smooth mountain ) or menadena ( transl.  isolated mountain ). In this context, monadnock

1681-458: Was discovered in a small area of Socopó Ridge in Falcón at 520 metres (1,710 ft). The frog, considered critically endangered, was found in 2004 in a small marsh beside a dirt road and in calm sections of a small stream. The surrounding area was cloud forest that had been cleared to create cattle pasture. The endangered red siskin ( Spinus cucullatus ) is found in the ecoregion in the Lara–Falcón valleys. Although protected by law, as of 2016

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