Tags
animals, Conservation, endangered, IUCN, nature, Red List, species
The most recent endangered species list posted on this blog – Endangered Species 2010: Fish Part 1 – Actinopterygii – featured the ruddy great Atlantic goliath grouper (Epinephus itajara), a critically endangered, sub-tropical, widely distributed reef predator.
It’s like the Sarlaac, only in the sea. With a fish head. And no tentacles. Alright, it’s nothing like the Sarlaac really. It is however an excellent image. © Douglas David Seifert
While browsing through the back issues of the open-access Endangered Species Research journal, I came across volume 7 number 3; a themed issue dealing with the ‘Range-wide status and conservation of the Goliath grouper’.
“This THEME SECTION of ESR focuses on the Range-wide status of the Goliath grouper. The goliath grouper Epinephelus itajara is one of the world’s largest and longest lived epinephalids. Heavily targeted by artisanal and recreational fisheries throughout its broad distributional range, the global declines in abundance and extirpation of goliath grouper spawning aggregations are of growing concern. Innovative research and management approaches coupled with international collaborative efforts are needed to address this pressing conservation problem. “
Just in case you missed the link-tastic text above and are even a little interested, you can also click here, here or here to go and do some goliath grouper-related reading.
The dwarf sturgeon is a relative of the 
This giant of the Mekon delta, China, is threatened by harvesting – it is a popular and important food fish – and habitat alteration. The construction of the first dams built on the Mekong, one of the world’s longest rivers, and its tributaries began in the late 1980′s. The ecological havoc wreaked by these dams has emperiled many species. Once relatively abundant, P. sanitwongsei now appears to persist in two sub-populations either side of Khone Falls.
S. ezenami is endemic to Lake Kenzio-am, a small (2.4km^2) water-body in northern Caucasus, Russia. The trout was the only fish present in the lake and tributaries until the introduction of the Caspian gudgeon (Gobio holurus) and the European chub (Squalius cephalus). The latter species is particularly problematic as it feeds on the fry of S. ezenami. Specific information is scarce though it does appear that the species has been successfully introduced to Lake Mochokh, Daghestan.
There is little information available on the wild status of this species. Endemic to the Chao Phraya and Mekong basins of Cambodia, Laos and Thailand, it is a popular aquarium fish which appears to breed well in captivity (though exploitation of wild stocks may continue). Habitat alteration may also be a threat.
The red-finned blue-eye is endemic to Australia where it inhabits five freshwater springs at Edgbaston Springs, Queensland. It is the smallest of Australia’s freshwater fish species with a length of just 30mm. The size and temperature of the springs are subject to seasonal flux and it is thought the blue-eye uses seasonal floods as a means of migration and dispersal. It is thought that there are at most a few thousand individuals remaining.
R. valsanicola was previously found in fast-flowing waters of the River Arges, Romania, and its associated tributaries of Valsan and Raul Doamnei. The species disappeared from the Arges due to the construction of a reservoir in 1965. It is now restricted to 1km of the Vaslan river where it is threatened by overfishing, pollution, stone extraction and upriver damming activities.
This species is a live-bearer (gives birth to live young) endemic to Monterrey, Mexico. It is a popular aquarium and biological research species. There are fewer than 250 wild individuals remaining, spread between several fragmented sub-populations.
T. turskyi is restricted to an area of occupancy of less than 10km^2 in the Cikola river, Croatia. The species was thought extinct until a population was discovered in 2002. The dominant threats are water extraction, pollution and drought.
The Chinese paddlefish (the ‘giant panda of the rivers’) is one of two extant paddlefish species and is one of the largest freshwater fish in the world with a length of up to (and probably over) 7 metres. The species inhabits the Yangtze River, China, where the Gezhouba Dam has fragmented the habitat, preventing adults from reaching the upper parts of the river to spawn. The species has been subject to intense fishing and its young are easily netted due to their schooling habits. It has not been possible to breed the species in captivity and it is considered to be on the brink of extinction.
C. pennanti is a whitefish belonging to the Salmonidae (the salmon family). It is endemic to Lake Tegid, a 4km^2 waterbody in Snowdonia, Wales and may now be established in Llyn Arenig through relocation efforts. Primary threats are water degredation, seasonal hypoxia at depth and predation on eggs, fry and spawning adults by introduced ruffe (Gymnocephalus cernuus).
E. itajara is a large (2.5m in length; 350kg+) marine grouper. Mature adults are apex predators and thus exist at low densities on reefs where they hunt other fish and invertebrates. The species is a popular food item. Overfishing, a slow growth rate and loss of suitable juvenile habitat saw catches decline significantly; harvesting has been prohibited across some of the species range since 1990 (USA; Brazil – 2002; US Caribbean – 1993. See the 
S. poulsoni may be one of the rarest freshwater fish in the world. It is known from a single underground cave system (Key Cave, Alabama) where it migrates between pools during seasonal floods. Though deep pools are known within the cave system, no specimens have been identified therein. The fish are almost devoid of pigment and are entirely eyeless, relying on sensory papillae, neuromasts (‘tactile sensory organs’) and an exaggerated lateral line system for navigation and foraging. It is thought that there are 100 individuals within the cave system. They are threatened by groundwater pollution and a decline in the numbers of cave bats whose guano nutrifies the pools.
C. cavernicola is known from a single pool (18m x 2.5m; 30 – 52ft deep) in the Aigamas Cave, Namibia, where it inhabits shallow water shelves. It is a sightless species whose population size is unknown. Primary threats are collection for the aquarium trade and groundwater extraction.
Spengler’s freshwater mussel was listed as ‘vulnerable’ on the 1990 Red List, ‘endangered’ in 1994 and has been listed as ‘critically endangered’ since 1996. It is endemic to France (mid Loire), northern Italy (mid Po) and Spain (Ebro), though the Spanish population does not appear to be producing juveniles. This species previously inhabited much of western Europe and northern Africa.
Previously found in thirteen states, the last known surviving population of this freshwater mussel exists in 20km of the St. Croix river between Minnesota and Wisconsin. The host fish for the larvae of this species is unknown, limiting the effectiveness of action plans. There are between 50 and 1000 individuals remaining.
Gastropods (lit. ‘stomach-foot’) are the most speciose of the molluscs with over 62,000 known species; that’s around 80% of all known molluscs. They are the only mollusc group to have successfully colonised terrestrial habitats. Gastropods are distributed around the globe, inhabiting almost every ecosystem, including forests, lakes, deserts, estuaries, the deep ocean, hydrothermal vents and intertidal zones.
Endemic to Suan Lamba, a limestone outcrop in Sabah, Malaysia, the natural habitat of this terrestrial snail species is calcareous subtropical or tropical moist lowland forests. The area of occurrence is around 1.5km^2; the surrounding habitat is in decline due to logging and quarrying which has already resulted in the extirpation of two sub-populations. It is threatened by habitat loss.
The partulids are a genus of land snails endemic to French Polynesia which provide excellent examples of adaptive radiation and the problems of invasive species. The African giant land snail (Achatina fulica) was introduced to the Society Islands where is swiftly became a pest. The predatory snail, Euglandina rosea was subsequently introduced to control A. fulica. Unfortunately, E. rosea found the various Partula species to be more palatable and by the end of the 20th century, 62 Society Island species had been reduced to 5. Many threatened species now only exist in ex-situ breeding programmes though several reintroduction trials have taken place.
H. cracherodii is a large mollusk of sub and intertidal habitats of California and Baja California. Though abundant enough to sustain a commercial fishery from 1968, a wasting disease considerably reduced commercial catch sizes and the population declined by more than 80%. The impacts of the disease (which is still present and progressing across the entire population) and overfishing, combined with limited dispersal capabilities mean that continued decline is likely.
There are over 9,000 known species of annelids, most of which are aquatic. The most well-known annelids are the ubiquitous earthworms (the largest of which – the Giant Earthworm, Michrochaetus rappi - can grow to a length of over 130cm), tubifex (common aquarium feed), ragworms, lugworms and of course, the much maligned leeches.
Lamprey are not true fish. Rather, the Petromyzontiformes are a group of jawless, largely parastic, marine species which are eel-like in appearance and have a many-toothed sucker-like mouth. This sucker is both a tool for feeding and, in anadromous and freshwater species, for travelling upstream, sucking on rocks or larger travelling fish.
Native to the Caribbean, southern Gulf of Mexico, Florida and the Bahamas, this coral has experienced a population decline of over 80% in the past three decades. Current populations exist in Broward County (Florida), Mona Island (Puerto Rico), places in the southern Caribbean, and Dairy Bull Reef in northern Jamaica. Climate change, disease, predation, bleaching events, pollution and anthropogenic factors are threats to this shallow-reef species.
A. palmata has a more restricted distribution than its shallow-reef neighbour A. cervicornis, stopping short of Fowey Rocks, Miami. Nevertheless, the general distributions coincide – the Caribbean, the Gulf of Mexico, Florida, and the Bahamas - as do the rates of decline (over 80% in 30 years) and the primary threats (climate change, disease, predation, bleaching events, pollution and anthropogenic factors).
Prior to the 1982-83 El Nino event which struck the Pacific southeast, this endemic of the Galapagos was observed to be extremely abundant. Subsequent to this event, all known colonies were lost. While three new colonies were discovered, it now appears that these too have been extirpated. The species has seen a decline of more than 90% since 1982; it would appear to be extremely sensitive to thermal anomalies.
P. pukoensis is endemic to protected shallow-water reefs in Hawaii. It is known from only one location within a range of less than 100km^2. While there is no evidence of decline, the limited area of occurrence qualifies the species for inclusion on the CR list under Criterion D. Coral disease and climate change are threats to all coral species.
Velvet worms are carnivorous animals which inhabit tropical and temperate forests at the equator and in the southern hemisphere. While related to arthropods, they are primitive in appearance and are considered key species in understanding arthropod evolution. Velvet worms have a peculiar and fascinating method of capturing their prey: they are able to shoot jets of sticky slime from papillae either side of the head. There are around 200 known species.
This Californian beetle exhibits a life history which is in synchrony with vernal pool habitats, specifically those of California. These pools occur in areas of poor drainage and fill with water during the winter rains. Emergence and dormancy in the beetle are cued by the filling and subsequent drying of these pools. Agricultural development and urban encroachment has eliminated or degraded much of this habitat and mat-forming invasive plants restrict foraging. There are several fragmented sub-populations restricted to Solano County, though most occur on private land and require negotiated protection.
Lice are ectoparasites, variously feeding on the skin, debris, blood and sebaceous secretions of the host organism. The majority of louse species are host-specific, that is, they are only capable of surviving on a single species. H. oliveri is such a species, residing on and migrating between the bodies of the pygmy hogs (Porcula salvania) of India. Thus the fates of the lice are inexorably linked to those of their porcine hosts. Unfortunately, due to habitat destruction and degradation, agricultural activities and human encroachment, there are fewer than 250 mature pygmy hogs surviving in the wild.
Franklin’s bumblebee is described as having possibly the most limited distribution of any bumblebee species in the world; certainly of those inhabiting North America. Its range encompasses a rough oval of 305km (North to South) x 70km (East to West) between Oregon and California. Fairly common in 1998, numbers declined so dramatically that just 6 years later, in 2004, none were observed. One individual was found in 2006. Threats include habitat loss, pesticides and pollution and exotic diseases from introduced commercial hives.
The Cromwell chafer is a scarab beetle endemic to New Zealand. As the common name attests, it is found in Cromwell, Otago; or, to be more specific, in an 81 hectare reserve (the Cromwell Chafer Beetle Nature Reserve) between Bannockburn and Cromwell. Four sub-populations are known to exist within the reserve, associated with wind-blown sand dunes, cushion plant (Raoulia australis) and silver tussock (Poa cita). The species is threatened by habitat degradation and predation by introduced species and the little owl. (Athene noctua) Curiously, large areas of apparently favourable habitat remain uninhabited, suggesting that the limiting factors are poorly understood.
Tenebrionids, otherwise known as darkling beetles, are a globally distributed family of over 20,000 species. They are all herbivorous/detrivorous, consuming fresh and decaying vegetation. P. herculeanus is the largest of the tenebrionids, attaining a length of up to 30mm. When alarmed, the beetle secretes a musky chemical which also stains the skin purple. Being restricted to Frégate Island in the Seychelles, the species has a range of just 2.19 km^2. The species proved resilient to the arrival of humans and brown rats on the island. However, the beetle is particularly associated with the sanddragon tree (Pterocarpus indicus) which is currently being affected by a fungal disease. As with all similarly restricted species, the beetle is also vulnerable to the effects of invasive species and natural disasters.
The St. Helena earwig is the only one of more than 1,800 described earwig (Dermaptera) species to be listed on the IUCN Red List. It is also the largest of the earwigs, measuring up to 83mm in length. The species is endemic to the island of St. Helena in the South Atlantic (an area of roughly 122 km^2) where it typically inhabits gumwood forests and seabird colonies. Originally described in 1798, it was not collected again until 1913. Recent surveys failed to find nymphs or fossil cerci (the paired rear appendages) and it is feared that the clearing of the gumwood forest coupled with the impact of an introduced centipede (Scolopendra morsitans) may have driven the species to extinction.
A species of dragonfly endemic to Sáo Tomé and Príncipe where it probably inhabits rainforest streams. It has a range of occurrence no larger than 50km^2 and is threatened by habitat loss. At least half of the island (139km^2 area) has been deforested.
The dramatically named dracula ants of Madagascar are a relatively recent discovery; the first individuals were described in 1994 and a colony was not discovered until 2001. They are considered to be a primitive ant species, representing the link between modern ants and a hymenopteran wasp ancestor. This link is borne out by the number of joints between thorax and abdomen (one as opposed to two or three in other ants). Their curious method of feeding whereby they consume the hemolymph (‘blood’) of their own larvae via incision in a non-lethal manner may be a precursor to trophallaxis (passing food from mouth/anus to mouth) in modern ants. Habitat loss is a significant threat to the majority of Madagascan wildlife. It has been posited that this particular species may be extinct within ten years.
Endemic to the Valle d’Aosta in the Italian Alps, this butterfly exists in three fragmented sub-populations within an area of less than 10km^2. The population continues to decline; reductions of between 6 and 30% have been reported. The isolated nature of the preferred habitat means that there are few opportunities for dispersal, meaning that the species is highly unlikely to colonise other favourable areas. It is possible that there are a few thousand individuals remaining. Invasive plants and habitat alteration (here in the form of natural succession) are the primary threats. Collection for international trade could also be an issue despite restrictions on such activities at the main site.
D. australis exists on the Lord Howe Island group, 600km off the eastern coast of Australia in the Tasman Sea. They are large, heavy-bodied stick insects. The species was believed to have become extinct in the 1920′s after rats were introduced to the largest landmass in the group, Lord Howe Island. In 2001, a population was discovered on Ball’s Pyramid, a 1844 feet tall volcanic stack some 23km from Lord Howe Island. The insects were found under a single shrub; their current population is unknown though it is unlikely that there are more than 30 individuals. The captive population – borne of two pairs removed from Ball’s Pyramid – numbers in excess of 450 individuals, 20 of which have been returned to a protected zone on Lord Howe Island.
The Ogasawara Islands, also known as the Bonin Islands, are a 30-strong archipelago 1,000km South of Tokyo, Japan. A relatively large proportion of the species which inhabit these islands are endemic. Many are included on the IUCN Red List as a result of habitat destruction and the impacts of invasive species. R. ogasawarensis is one of five odonates (dragonflies and damselflies) endemic to the islands. It has seen its range reduce as suitable aquatic habitat has been destroyed or polluted. Predation by birds and the invasive lizard Anolis carolinensis (the Carolina anole) may also be problematic.
The beautiful metallic blue peacock tarantula was first discovered in a timber yard of Gooty, India in 1899. Despite frequent and resolute surveys, the species was not rediscovered for another 102 years when individuals were found in a forest some distance from the original site. They are arboreal creatures, living in tall trees where they feed on insects. There is no information available on the current size of the population. However, P. metallica exists within a restricted range of less than 100km^2. Habitat quality is declining and, due to the striking colouration, it is a highly sought-after species for the international pet trade.
Like all amphipods, G. desperatus is small and shrimp-like, lacking a carapace and exhibiting lateral compression. It is a freshwater species of well-oxygenated streams, ponds and springs. Primary threats are habitat loss, degredation and pollution. Two of the three known sub-populations have been lost in the last century; the only known surviving population exists at Bitter Lake National Wildlife Refuge, New Mexico, USA.
Crayfish are freshwater relatives of lobsters; the famous langoustine or spiny lobster is a marine crustacean which is sometimes referred to by the name ‘crayfish’ though to call it such is, taxonomically speaking, a misnomer. The Shasta crayfish is endemic to Shasta County, California where it exists in fragmented sub-populations of the Pit River drainage. Migration between sub-populations, while being disturbed by natural barriers, is also inhibited by hydroelectric development and habitat degradation. Further threats come in the form of invasive crayfish species, including the infamous signal crayfish (Pacifastacus leniusculus). Based on previous surveys, the current population may be as low as 3,000.
The worst case scenario in the most recent IUCN Red List survey of freshwater crabs suggested that around two-thirds of all species are at risk of extinction as a result of habitat destruction, pollution and drainage. While the most optimistic scenario is that only 16% of species are thus endangered (227 identified), the prevalence of stated threats and the fact that 628 species are data deficient means that this lower estimate is highly unlikely to be accurate. The Singapore freshwater crab was originally known from two locations, though one of these has been extirpated due to water acidification. The second population occurs in area of less than 100km^2 in a streamlet near Buit Batok where it hides beneath rocks and in vegetation. This remaining population is under severe threat from habitat development and degradation.
The millipedes of the genus Doratogonus are relatively large at between 80 and 200 millimetres and are distributed across South Africa at varying levels of abundance. D. major is a species of woodland; specifically, Gwaliweni Forest in northern KwaZulu-Natal, an area of around 11km^2, where it lives in the soil and leaf litter. Only a small number of specimens have been collected despite their size, leading to the suggestion that the population density may be very low. The primary threats to this species are habitat destruction (for fuel and building materials locally) and the various problems faced by species which exist in low numbers.
C. ampla is a perennial tree shrub which inhabits lower humid montane forests of Puerto Rico. The population is fragmented across half a dozen sites all within the Palo Colorado forest in the
Mauritius has been widely decimated by invasive species. Indeed, the bois dentelle is now only located on a single hill (Piton Grand Bassin ) close to an Indian temple; the hill itself has been invaded and E. bojeri directly affected by guava (Psidium cattleianum) and Litsea monopetala, an evergreen shrub. Propagation of seeds from a transplanted individual and grafting attempts have been successful. However, fewer than 10 adult trees remain in the wild.
I couldn’t let this list pass by without mentioning this rarity from my home country (and indeed, my home county for three years) . The Snowdonia hawkweed was discovered in 1892 and was not classified as a distinct species until 1955. 1n 1967, it was thought to have gone extinct due to excessive grazing. The species was rediscovered in 2002 and is now considered to be one of the rarest plants in the world. It grows on rocky, inaccessible north-facing cliffs and it is thought that the species has long been restricted in range and abundance. Though seeds have been collected for propagation, there currently exists but one known specimen in the wild. Thus the location of this specimen is protected and proactive management to remove grazers, prevent rock-fall, etc. is a priority.
Found on Robinson Crusoe Island (appropriately named, for the island is where the real Robinson Crusoe was stranded in C18) in the South Pacific, this member of the Asteracea (sunflower) family vies with the aforementioned Snowdonia hawkweed for the title of ‘World’s Rarest Plant’ as there is but a single specimen remaining in the wild (other individuals have been propagated ex-situ). The island itself has a total area of around 50km^2 and what endemic flora remains is subjected to grazing by introduced rabbits and goats and fast-growing, adaptable, aggressive invasive plants.
place a family level taxon on these lists again, it seemed appropriate in this instance; of the 500 extant species of dipterocarp, over half (approximately 280) are listed as critically endangered by the IUCN. The primary threat to these species is, as ever, habitat loss, habitat conversion and harvesting. In Indonesia, vast swathes of land have been variously burned, logged and converted into oil palm, rubber or industrial timber plantations. Other regions have been affected by oil and coal exploration and wetland drainage. As these species are significant contributors to large and extremely speciose rainforests, ecosystem function will be compromised well in advance of their eventual demise which will, in turn, inevitably have countless significant and irreversible knock-on effects.
This species is a vine or liana which classically inhabits steep slopes and level ground in dry, coastal, mesic and mixed mesic forests on the Hawai’ian islands of Hawai’i, Maui, Lana’i, Oahu and Kaua’i. The total population may be several hundred strong. However, it is thought that fewer than 250 of these are mature specimens. The species is threatened by agriculture, habitat development, fire and invasive flora and fauna.
P. kawakamii is, like many of the genus, a popular ornamental species due to its attractive blooms and foliage. Japanese tradition dictates the planting of a Paulownia next to the house for protection when a daughter is born; a wedding chest is eventually made from the timber. P. kawakamii is found in mixed evergreen forest of the Chiayang area, Taiwan. The most recent survey in 1998 described only 13 mature trees due to the combined threats of habitat conversion for apple and peach orchards and exploitation for timber.
As the common name attests, this species is indeed a member of the mallow family which includes okra and the infamous cacao, or cocoa tree. A. eremitopetalum is a shrub endemic to the dry forests and shrublands of Lana’i, Hawai’i. The only known population exists in an area of less than 10km^2 and is fenced off to protect the specimens from deer. This method of grazing prevention seems to have been effective as the number of individuals has risen from around 40 in the mid 90′s to around 100 as of 2003. However, introduced grazers (deer and mouflon sheep) remain a serious threat. Further threats include invasive plants, fire, drought and loss of pollinators.
One of several ivy trees endemic to the Hawai’ian islands, T. gymnocarpa is most frequently found in cloud forest of the koolau mountains and less frequently on ridges and in other moist forests of the area on the island of Oahu. According to the IUCN Red List, only 16 sub-populations of this species remain, with few sub-populations exceeding four individuals. The remaining plants are threatened by alien species and feral ungulates.
Soccarell bord is a spiny shrub of the Balearic islands where it inhabits dry, sandy soils. While this perennial species thrives in sunny locations and is protected from herbivores by its tough spines, it has a limited dispersal ability and it thus a limited capacity for recovery and/or expansion. It is threatened by habitat development, invasive pests and is often removed from public areas due to its spines. In total, Soccarell bord occupies an area of less than 100 km^2, wherein fewer than 2,200 mature individuals are split into six fragmented sub-populations.
A member of the Campanulaceae family (otherwise known as bellflowers; not to be confused with bluebells; family Hyacinthaceae), the large bellflower has an estimated wild population of fewer than 50 adult individuals. There has been a marked decline of both mature specimens and seedlings within each of the three known sub-populations which themselves are fragmented. Invasive species (primarily flax and fuchsia) and habitat degradation are severe threats.
Khadia beswickii is a member of the Aizoaceae family, a group of succulents otherwise known as ‘stone plants’. This particular species is endemic to the Gauteng Province of South Africa where it exists within a range of less than 250km^2. Like most Khadia species, K. beswickii forms low clumps in rocky habitat and are capable of withstanding fires. There are three sub-populations with a total mature population of less than 250 individuals. Primary threats are invasive species, collection and habitat degradation and development.
The wild population of this Spanish brassica has been declared extinct in the wild once already; the last remaining population disappeared from Alboran Island in 1979. The species was re-introduced in1999 using propagated seeds recovered prior to its extinction. Though the species has exhibited tolerance for human disturbance and exists on what is now a protected islet, past human interference and the introduction of cattle have left the island with an even more fragile and vulnerable ecosystem than would otherwise have been the case. Additionally, scientists are unsure whether the population of 48 plants re-introduced in 1999 is self-sustaining.
The Sebucan is a cactus endemic to Puerto Rico and the British Virgin Islands where it inhabits limestone cays in dry forests and shrubland. The clumping nature of the cactus has made accurate population counts impossible. Nevertheless, it has been stated that the total number of individuals in the wild is less than 50 and is possibly as low as 35. Habitat fragmentation and development and, in one location, rising sea levels from global warming, are primary threats.
This species is only known from two collections; one at the beginning of the nineteenth century and one in the 1970′s (the photo is of another Flueggea species). Though the collections were known to be made in Ecuador, the exact locale is unknown. The species is listed as CR due to the extensive alteration of coastal habitat in Ecuador. Indeed, if the species is still extant, habitat degradation is the greatest threat.
As the common name attests, this legume is endemic to the island of Moloka’i, Hawai’i where it inhabits dry and mesic forests. Its range has been severely reduced by the impacts of grazing animals such as pigs and goats and invasive plant species. As is often the case with endangered plants, little is known about its reproductive strategy and pollinators. There are current 4 fragmented sub-populations in an area of less than 100km^2. The total mature population is between 200 and 400.
This tree was originally discovered in Smyth County, Virginia, USA, in 1914. Living specimens then eluded researchers for nearly 60 years until the discovery of a population along Cressy Creek in 1975. The Virginia round-leaf has been described as possibly the most endangered tree species in the US, an apt description as it is only known to inhabit a 1km stretch of river and numbers have fallen from 41 to 11 (as of 1998). 20 sub-populations have been established as part of a replanting programme.
S. sebaeoides is endemic to the islands of Kaua’i, Oahu, Molokai, Maui and Lana’i, in Hawaii. The population has suffered dramatic and catastrophic losses due to drought, with numbers falling from 6,300 – 6,600 individuals in 1997 to 60 – 80 in 11 fragmented sub-populations in1999. While such dramatic ‘boom and bust’ fluctuations are somewhat characteristic of species which utilise seed-banks specifically exploit favourable conditions (as is the case with the awiwi), the extremely low numbers reported in the last survey ensure it remains a CR listed species. Other threats include habitat degradation and development, fire, invasive plants and trampling. Note: the species was formerly classified in the genus Centaurium [3] but was re-assessed in 2004, one year after the IUCN assessment.
W. nobilis is the sole extant species of the Wollemia genus and was only known from Mesozoic fossils before live specimens were discovered in the gorges of Wollemia National Park, Australia in 1994. Clones of the wild specimens are sought-after for decorative horticulture but in-situ there are only less than 100 known individuals, fewer than 50 of which are mature. The main threats would appear to be interspecific competition and introduced pathogens.
The type specimen for this species was cypress was first described in 1899 and 1900 in Chongqing Municipality, Sichuan, China. No specimens were reported again and the species was presumed to be extinct until 1999 when stunted individuals were found at the same location of the discovery of a century earlier. Large and easily accessible specimens were felled for house building and wood-craft; the remaining individuals inhabit exposed ridges at altitude where they are stunted by environmental pressures. The remaining individuals exist in one remote sub-population where inbreeding is considered to be a threat.
This species is known from one habitat: granite outcrops on Khao Chamao mountain, Thailand. While this species is common in local gardens, it is under threat from collectors which has led to wide scale depletion.
Originally described in 1926 in Mexico, Z. monticola was presumed extinct until specimens were collected from Guatemala. Its status on the Red List reflects the apparent lack of ovulate cones in the population and the dearth of information regarding population size.
A bottle palm – so called for their swollen trunks – of lowland savannah on Round Island, Mauritius, H. lagenicaulus is abundant throughout the tropics where it is a popular show species. The species has declined due to the impacts of invasive rabbits, goats and weeds and habitat destruction. The invasive species were successfully eradicated some time ago, after which time indigenous species were observed to be growing prolifically. While there is cause for optimism, the Red List reports that fewer than 10 mature H. lagenicaulis trees remain in the wild (though the page is noted as requiring updating).
One of many critically endangered Ecuadorian plant species, T. dyeriana is known from two sub-populations. Though it is not known to exist in the Ecuadorian protected areas network, that does not necessarily mean that it is absent. The species is an epiphyte of mangrove forests; habitat loss is the primary threat.
As the name suggests, the bastard quiver tree belongs to the same genus as the familiar medicinal succulent Aloe vera. Unlike A. vera, A. pillansii is capable of growing up to 10m in height. It is located mainly in the Richtersveld region of the Northern Cape Province of South Africa; reports of specimens north of this location are apparently unsubstantiated. The wild population does not appear to be regenerating; there has been little reproduction in the last century and older individuals are dying. The species is also threatened by collectors, climate change and herbivory.
Fewer than 600 individuals of this perennial squill species are known, separated into three isolated sub-populations and all within an area of less than 2km^2 in north-western Cyprus. The plant largely grows in the field layer of old oak woodlands or in shaded crevices and banks. The population appears to be stable. However, habitat conversion and road construction are present and growing threats.
