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SPECIES YOU DIDN’T KNOW EXISTED | ||
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In celebration of the International Year of Biodiversity, we will showcase a newly discovered or less well-known species or group every week during 2010. December 14, 2010 Glomeremus orchidophilusMany plants depend on animal pollinators such as bees and bats. The relationships between plants and their pollinators are close and intricate, and plants often develop complex structures to attract them. Crickets and their relatives (e.g. locusts) can be voracious herbivores, sometimes causing important damage to crops. They have never before been known to be active pollinators, although some incidental pollination is known to take place when crickets feed on nectar or pollen, and some pollen transfer occurs. A newly described cricket species from the island of Reunion was seen actively and repeatedly pollinating an orchid (Angraecum cadetii ). Researchers wanted to know which species was pollinating this endemic orchid, and set up cameras to shoot the orchids during the night. They observed a cricket visiting flowering orchid patches every night, and described what they observed as follows: [crickets were] “...probing deeply into the orchid spur, the head totally hidden in the centre of the flower, and visiting the majority of ‘fresh-looking’ flowers within reach.” (Hugel et al. 2010). The crickets were never observed eating any part of the plant but rather orchid pollen packets became stuck to the heads of the crickets, which were then transferred to other flowers. This orchid loving cricket was aptly named Glomeremus orchidophilus. To see a video of Glomeremus orchidophilus in action click here. To learn more: December 8, 2010 Anaerobic animalsSeveral kinds of organisms- including bacteria, protozoans, and some protists- can live their whole lives in the absence of oxygen. However, until now, no multicellular animal was thought to be able to tolerate anoxic conditions for more than brief periods. A team of scientists working in the deep L’Atalante Basin in the Mediterranean discovered 3 new species of Loriciferans, living in permanently anoxic ecosystems. By finding organisms in different life stages in the same site, they were able to infer that they do live their whole lives in anoxic conditions. Using a variety of biochemical and microscopy techniques, the team was also able to show that these animals were metabolically active in an anoxic environment and that they have a specific set of adaptations that allow them to live in the extreme conditions of this deep, anoxic ecosystem. This is the first report of a multicellular animal able to live without oxygen, and suggests that more animal species can be found in environments where we previously thought they could not survive. For a picture of one of these species, please click here. To learn more: Anaerobic metazoans: No longer an oxymoron November 30, 2010 Stenolemus bituberusSome predators stalk and ambush their prey once they (the predators) come within striking distance. Others use complex strategies to lure the prey into coming within their range. For example, some fireflies mimic the light signals used by females of other firefly species to lure the males which become their prey. Stenolemus bituberus, an insect that preys on spiders, can do both. They can slowly approach unsuspecting spiders until they get close enough for an attack. But they also engage in "deceptive communication", misleading the spiders to come closer. Web-building spiders respond to vibrations in their webs to detect and locate trapped insects. S. bituberus also approach a spider’s web and mimic the vibration patterns of struggling insects, causing the web’s owner to come to inspect what seems like a fresh capture, only to become prey themselves. This "aggressive mimicry" precisely mimics the vibrations made by prey, and is different from the vibration patterns made by male spiders, leaves, or insects only moving their wings. For a picture of Stenolemus bituberus click here. [Species suggested by S. Harte] To learn more: November 16, 2010 Leiolepis ngovantriiA scientist visiting a restaurant in Vietnam noticed a talk full of lizards that all looked strangely similar to each other. Lizards in this genus are dimorphic, meaning that males and females have distinct external features, so he suspected this group of animals as unique. Scientists from the University of Kansas later discovered that this new species is composed entirely of females that reproduce asexually. Asexual reproduction is rare in vertebrates, but it is known to occur in several species of fish and reptiles. When they analyzed their DNA, they found evidence that this new species is a hybrid of closely related species living in this area. Hybridization is also not uncommon in nature, especially when closely related species overlap. To see a picture of Leiolepis ngovantrii click here. [Contributed by S. Harte] To learn more: Grismmer & Grismmer. 2010. Who's your mommy? Identifying maternal ancestors of asexual species of Leiolepis Cuvier, 1829 and the description of a new endemic species of asexual Leiolepis Cuvier, 1829 from Southern Vietnam. ZOOTAXA Issue: 2433 Pages: 47-61 November 8, 2010 Red alert: Wallabicoris ellae and Curalium cronini[Text contributed by Laura Allen of the American Museum of Natural History]
Despite their bright coloration, these two insect species were only recently known to entomologists. Identified by Randall T. Schuh, the George Willet Curator of Invertebrate Zoology at AMNH, the new discoveries represent the vast unknown diversity of true bugs the order Hemiptera. The bright red species above was captured in a UV light trap near Gainesville, Florida and named Curalium cronini after the latin word for “red coral” and J. Eric Cronin, the collector. The bug is only 1.5 mm long. Entomologists hope to observe it—as challenging as that may be—alive in the wild.
The carmine-speckled bug above, Wallabicoris ellae, is a comparative giant at 5.5 millimeters long. Schuh found the bug crawling on a shrub with purple wildflowers while scouring the Western Australian outback for new species. Western Australia hosts an immense variety of wildflowers—perhaps more than 12,000 species. The bugs that inhabit them appear to be quite diverse as well: most of the bug species were found only on a single type of plant. To see more creatures recently discovered by AMNH scientists, watch the new Bio Bulletin, In Search of Wild Variety, produced by the AMNH Science Bulletins program. October 26, 2010 Spiroplasma sp.
Last week’s species was affected by a parasitic castrator – a kind of parasitic interaction that results in strongly negative effects over their host’s reproduction, and therefore it can be predicted that natural selection would favor mechanisms to escape the devastating effects of parasitic castration. Spiroplasma is a genus of bacteria whose species are often found in insects or plants. A species of Spiroplasma is transmitted maternally (i.e. infected mothers produce infected offspring) in the fruit fly Drosophila neotestacea. This fruit fly is often infected with a parasitic castrator nematode that renders infected female D. neotestacea completely sterile, and causes infected males to have low mating success. A recent study showed that Spiroplasma-infected flies are protected from the sterilizing effects of the nematodes. The bacteria appear to block the growth of the parasitic nematode. This fly-bacteria association is becoming more common through time, perhaps because of its protective effect. To learn more: October 19, 2010 Cheilodipterus quinquelineatus
Parasitic castration is a type of host-parasite interaction in which the outcome is that the reproductive capacities of the host (i.e. the individual being parasitized) are blocked or severely reduced. Infected hosts have no energetic expenditures on reproduction and have a longer lifespan, providing the castrator with a long-lived home that provides it (a single parasite individual is usually all it takes to produce castration) with extra resources. By modulating the host’s reproductive output, parasitic castrators modify their population ecology (for instance the hosts’ population density), change their behavior, lifespan, and can even create evolutionary pressures (for example by favoring hosts that reproduce early in life). Most known castrators affect invertebrate hosts such as crustaceans and snails. However, a recent paper describes that infection of the five-lined cardinalfish (Cheilodipterus quinquelineatus) with a single isopod (Anilocra apogonae; a crustacean) results in a lower chance of females developing ova at all, or had smaller or more immature ova. Infection also interfered with the males’ capacity to mouthbrood. Parasitic castration might be more common in vertebrates than previously thought. [Thanks to M. McCaffrey and S. Harte] To learn more: http://www.eol.org/pages/1012915 http://www.eol.org/pages/326903 October 13, 2010 Anisognathus lacrymosus yariguierumOf the approximately ten thousand known bird species in the world, over 1,900 are found in Colombia, making it the country with the highest bird diversity in the planet- for comparison, the number of bird species that spend at least part of their lives in the United States is under 900. Using morphometric, DNA, and song analyses, scientists at the Universidad de Los Andes in Bogotá discovered a previously unknown subspecies, and named it Anisognathus lacrymosus yariguierum in honor of a Native tribe that once lived in the area. This bird lives in the páramos, a unique type of high mountain ecosystem in Northern South America, currently under threat from encroachment and climate change. Scientists hope to use this discovery (and the other known 583 bird species in this ecosystem) to support the creation of a new protected area. Although several new bird species and subspecies have been discovered in Colombia in recent years, this is the first new tanager, a group of birds that is considered relatively well known. This finding confirms that we are still far from cataloguing the Earth’s biodiversity, and that we are likely losing species before they are known to science. To learn more: For a full report (in Spanish), a look at a distribution map, and a recording of the bird’s song, click here. October 5, 2010 Unknown marine biodiversityIn the year 2000 an international group of scientists designed a strategy to assess the world’s marine life, and try to find answers to the questions: What did live in the oceans? What does live in the oceans? What will live in the oceans? As planned, they released their findings in 2010, after more than 540 expeditions involving close to 3000 scientists from 80 countries. This unique initiative, the Census of Marine Life, discovered at least 6000 species previously unknown to science, but their results suggest that there could be tens or even hundreds of millions- the census is discovering potential new species at a much faster rate than their capacity to describe them. They also report that they found life everywhere they looked in the oceans, including places “where heat would melt lead, seawater froze to ice, and light and oxygen were lacking.” An image gallery from this project can be found here. To learn more: A marine life encyclopedia, The New York Times A plenitude of wonders, The New York Times Discovering the ocean’s microscopic world, BioBulletins, American Museum of Natural History September 29, 2010 Danionella draculaA new species of fish was described in 2009, from specimens collected in Myanmar in 2007. Related to the common aquarium-dweller zebrafish, D. dracula has several unique morphological characteristics (the title of the scientific paper that described the species is “Spectacular morphological novelty in a miniature cyprinid fish, Danionella dracula n. sp.”). It was described as “miniature and highly developmentally truncated cyprinid fish”. The largest known individual is only 16.7mm long, which is about half the size of its closest known relative. Compared to the zebrafish, 44 bones or parts of bones do not develop in D. dracula, making it “one of the most developmentally truncated vertebrates” (Britz et al., 2009), and its skeleton is described as having an overall larval appearance. Uniquely among this group of fishes, male D. dracula have a series of tooth-like bone projections that resemble fangs. The scientists naming the species were inspired by “Count Dracula in Bram Stoker's novel”. To see a picture of Danionella dracula, click here. To learn more: Britz et al. Spectacular morphological novelty in a miniature cyprinid fish, Danionella dracula n. sp. Proc. R. Soc. B 22 June 2009 vol. 276 no. 1665 2179-2186 September 22,2010 WolbachiaWolbachia is a genus of bacteria, whose species are maternally inherited (i.e. infected mothers beget infected offspring), intracellular symbionts of nematodes and arthropods. It has been estimated that Wolbachia species infect up to 70% of the world’s insects (itself the most speciose group on the planet), thereby being potentially the most widespread reproductive parasites on Earth. Wolbachia has evolved several strategies that increase its transmission efficiency, including: male killing, feminization (infected males develop as females), inducing parthenogenesis (infected females reproduce asexually- no male involvement is required), and cytoplasmic incompatibility (makes uninfected males unable to reproduce with infected females, and even creates a reproductive barrier between males and females infected with different strains). Mutualistic Wolbachia strains have key roles in the development of some of their nematode hosts, including the causative agents of lymphatic filariasis and onchocerciasis, which implies that targeting bacteria, can help control diseases caused by a nematode. Wolbachia, therefore, has important roles in the development, modification of sex ratios, and reproductive isolation of many nematode and arthropod species. Research is underway to understand the seemingly vast ecological and evolutionary significance of Wolbachia.
To learn more: Genome Sequence of the Intracellular Bacterium Wolbachia. PLoS Biol 2/3/2004: e76. http://dx.doi.org/10.1371/journal.pbio.0020076
September 14, 2010 Proteus anguinusProteus anguinus is a blind salamander endemic to caves in southern Europe. Known as Olm, P. anguinus is the only species in its genus and the only known Eropean vertebrate that is exclusively cave-dwelling. Olms are pale (internal organs can be seen through the skin, yet they have retained the capacity to produce skin pigments if exposed to light), slender and have small and poorly developed but light-sensitive eyes. They are entirely aquatic and unlike other amphibians, metamorphosis is absent in the olm. Instead, they retain larval characteristics (such as gills) throughout their lives. Olms are long lived (they can live for more than 50 years), and can survive without food for up to 10 years. Because they spend their lives in dark habitats, olms have developed acute senses to evaluate chemical, pressure, motion, and electrical signals. Although little is known about the abundance of this species, it is currently considered vulnerable, because of its limited range and the impact of human activities on the quality and quantity of subterranean aquifers.
To learn more: http://www.eol.org/pages/331216 http://www.edgeofexistence.org/amphibians/species_info.php?id=563 August 31, 2010 Microhyla nepenthicolaThe smallest known frog species known to date was recognized as a new species on August 19, 2010 following an expedition to Sarawak. Although individuals of Microhyla nepenthicola had been seen before, they were thought to be the juveniles of another species. Adults of M. nepenthicola are only 10.6- 12.8mm (just over a third of an inch) in length- the whole adult body is about the size of a pea. Miniaturization creates a special set of challenges. One of them is that there is higher area to volume ratio, which means that smaller individuals in terrestrial environments tend to desiccate faster. M. nepenthicola compensate for this risk by living in humid microhabitats- they are mainly nocturnal, live in association with a species of pitcher plant (Nephentes ampullaria) and remain inactive on drier nights. You can hear M. nepenthicola’s call in this webpage or by downloading an mp3 file here.
To learn more: Old World’s smallest frog is discovered in Borneo August 24, 2010 Hyperparasites
Parasitism is the most common lifestyle in the planet- more species engage in some form of parasitic exploitation than there are free-living ones (see this blog to learn more about parasite biodiversity). Given this level of diversity, it is not surprising that parasitic exploitation takes many forms. Parasitoids are organisms that spend a key part of their life cycle living in or on another which it exploits for nutrients and sometimes also for protection (there are indications that some parasitoids can manipulate their host’s behaviors so they start protecting them). Unlike parasites, parasitoids spend the other parts of their life cycles as free living species, and always kill their hosts (although they can also cause death, parasites can coexist with their hosts indefinitely without causing mortality). Hyperparasites further complicate this relationship: they are parasitoids of parasitoids. In this relationship a free-living insect is the host for a primary parasitoid, which in turn is the host for a hyperparasite. Hyperparasites appear to be restricted to 3 taxonomic orders: Hymenoptera (wasps, bees, and ants), Diptera (flies) and Coleoptera (beetles). As if this fourth trophic level relationship was not complex enough, hyperparasites have evolved a variety of different strategies; for example, some are facultative (able to be hyperparasites or primary parasitoids), and some are indirect (attacking the parasitoid by means of attacking the free-living host). Hyperparasitism is a complex and highly evolved relationship with important consequences for ecosystems and biological control programs.
August 17, 2010 Lutra sumatranaThe hairy nosed otter is the rarest of the five otter species living in Asia. Thought to be extinct the late 1980s, it has subsequently been spotted occasionally in Vietnam, Malaysia, Cambodia, and Indonesia. In 2010, a camera trap spotted an individual in Borneo, where the last known hairy nosed otter was a road killed specimen found in Brunei in 1997. The type specimen was collected in Sumatra – which explains its species name. Its common name comes from it having hairs in the mist part of the nose. It is currently classified as endangered and it is believed to be extinct throughout most of its range. Habitat loss and degradation, exploitation for meat and use in traditional medicine are the main threats against this extremely rare species.
To learn more: Rarest otter discovered in Sabah, Borneo Lubis, R. 2005. First
Recent Record of Hairy-Nosed Otter in Sumatra, Indonesia.
August 10, 2010 Himantura chaophraya
The giant freshwater stingray Himantura chaophraya, was formally described in 1990 (although it was known for years by then) from 3 specimens collected in the Chao Praya river in Thailand- hence the species name-, and is native to large rivers throughout Southeast Asia and northern Australia. Weighing over 500 kg, it is one of the largest freshwater fishes in the world. Besides its large body size, H. chaophraya is characterized by projecting snout ending in a triangular tip, small eyes and mouth, and a large serrated spine in the tail. Little is known about its ecology or natural history, but biometrical analyses of collected specimens suggest that there may be more than one phenotypically distinct population. The IUCN classifies this species as vulnerable due to its isolation along river basins, and the interaction among factors threatening freshwater species in that region of the world, such as habitat destruction and alteration. Although it is not a direct target for fishermen, it is often accidentally caught in fishing nets. [Species contributed by Dr. Martha M. Hurley]
To learn more: Monkolprasit S, Roberts T. 1990. Himantura-chaophraya, a new giant fresh-water stingray from Thailand. Japanese journal of ichthyology 37(3): 203-208 July 6, 2010 Grimpoteuthis sp.
Octopi species in the genus Grimpoteuthis are among the rarest members of the Order Octopoda (the taxonomic category that includes all octopi). Because they live in the deep ocean, and because they have fragile bodies, they are a difficult group to study. They are found in all oceans living at depths of at least 750 meters, but some species are found at 7,500 meters. Grimpoteuthis sp. are believed to be able shed the uppermost layer of skin at will. These species are sometimes referred to as “Dumbo octopi” because they have a pair or prominent fins that extend from the top of their bodies. They swim by moving the fins, pushing with their arms, pushing water through their funnel, or by using all three methods at one time. Click here to see a video of a Grimpoteuthis octopus in motion. Remarkably little is known about their ecology, reproduction, behavior, or conservation status. To learn more: Collection data in the Global Biodiversity Information Facility http://www.eol.org/pages/465536 http://www.eol.org/pages/3035001 June 23, 2010 Lamellibranchia sp.The deep ocean is a relatively nutrient-poor environment. Here, natural hydrocarbon vents provide nutrients and create the conditions in which some species can live and aggregate. In the depths of the Gulf of Mexico, off the coast of Louisiana, scientists discovered a kind of tubeworm with an extremely slow growth rate. These tubeworms, classified in the genus Lamellibranchia, take between 170 and 250 years to reach a length of 2 meters, making them the most long-lived non-colonial marine invertebrate known to science. The worms appear to grow episodically, with growth spurts interspersed with periods of slower growth. Throughout their long lives they provide substrate and nutrients to a variety of other species in that ecosystem. The consequences of the Gulf oil spill on species such as Lamellibranchia sp. are still unknown, but the damage to other species is already significant.
To learn more: Berquist, D.C. et al. 2000. Longevity record for deep-sea invertebrate. Nature 403: 499-500 June 16, 2010 Upis ceramboidesUpis ceramboides, or the roughened darkling beetle, is an elongated tenebrionid living in the boreal forests of Asia, Europe, and North America. They are found overwintering under the bark of dead standing trees above the snowline. Because of that, they are commonly exposed to extreme ambient temperatures, which are often below -55°C (-67°F). The beetles remain frozen during most of the boreal winter, which lasts about 6 months. To survive this long period of freezing without tissue damage, force water out of their cells (thereby avoiding sharp ice crystals), and produce an antifreeze compound unlike that of other freeze-tolerant plant and animals, which are protein based. The antifreeze in U. ceramboides is the first known antifreeze in nature that contains little protein, and is made up predominantly of xylomannan, a type of sugar.
To learn more: June 9, 2010 Osmia avosetta
A recent paper by a team led by Jerome Rozen of the American Museum of Natural History describes the unique nests of the bee Osmia avosetta. Nests of O. avosetta were found in 2009 in Turkey and Iran. The nests are made of chambers that are lined by 2 layers of flower petals that sandwich a layer of mud. Female O. avosetta dig a main tunnel and a cavity, and then collect large pieces of petals to make the exterior layer. Because a female can use a wide variety of flowers, these cells can be quite colorful. When the outer envelope is finished, a thin layer of mud is applied. After the mud sets, a new layer of petals is applied to line the cavity completely. Females then deposit a mixture of pollen and nectar on which they lay their eggs, before carefully closing the cells by folding the petals at the top.
To learn more: http://www.discoverlife.org/mp/20p?see=I_JSA1043 Osmia in the Encyclopedia of Life [Suggested by S. Harte] June 1,2010 Tachybaptus rufolavatusT. rufolavatus, the Alaotra Grebe, is the first confirmed bird extinction since 2008. A medium-sized bird incapable of long distance flight, the Alaotra Grebe’s range was limited to a small area in eastern Madagascar. Last sighted in 1985, the species was declared extinct in May 2010. Birds with some characteristic of the species were sighted in 1986 and 1988, but these individuals were thought to be hybrids with a closely related migratory species. Habitat loss, hybridization, and the combined impacts of entanglement in monofilament fishing nets, and the introduction of a carnivorous fish, caused this species’ extinction. Human actions, such as those that drove T. rufolavatus to extinction, threaten many species of all taxonomic groups in all of the world’s ecosystems. Many of them are unknown to science and are examples of species we will never know existed.
May 25, 2010 Swima bombiviridisA team of scientists at the Scripps Institution of Ocenaography recently described a previously unknown genus of worms living in deep waters in the Pacific Ocean. The team used remote controlled vehicles to find a new genus, of which the type (what they considered a “typical” organism for that group) is Swima bombiviridis. Species in the Swima genus appear to not be closely related to other known species, which means they represent a major evolutionary branch within their group (the Cirratuliformia, a kind of polychaete worm). S. bombiviridis, along with 4 other species in the genus, release bioluminescent “bombs” as part of their defensive behaviors (they are thought to distract predators and allow them to escape). The bombs are modified gills that can be cast off when under stress, and they will illuminate with green bioluminescence for several seconds after being released. Each individual carries up to 8 of these bombs. This bomb-releasing behavior is also new to science.
To learn more: http://scrippsnews.ucsd.edu/Releases/?releaseID=1012 May 18, 2010 Magnetotactic bacteriaMagnetotactic bacteria are a very heterogeneous group of prokaryotic organisms belong to many species (in fact, they form a very diverse group) that have in common a unique organelle, called a magnetosome, that aligns the cell along magnetic field lines. Magnetosomes contain magnetic crystals of iron oxide or sulfide in shapes that differ among bacteria species. Magnetotactic bacteria in the Northern and Southern hemispheres have opposite predominant migration directions, having evolved to align themselves with respect to the Earth’s magnetic field in each hemisphere. These bacteria live in chemically-stratified water columns, and their alignment according to the Earth’s magnetic field is thought to aid in keeping them within regions of appropriate oxygen concentrations.
To learn more: http://www.calpoly.edu/~rfrankel/NatRevMicro.pdf May 11, 2010 Craseonycteris thonglongyaiKitti’s hog-nosed bat or the bumblebee bat is the smallest bat species, and one of the smallest mammals in the world- their body length ranges from 22 to 26 mm (1.1 to 1.3 in), and their body mass is around 2 g (0.07 oz). As one of their common names implies, they have distinctive pig-like snouts with crescent-shaped nostrils. They are so distinctive morphologically, that it is classified as the only species in its family. They are found in very small groups (their whole population might be just a couple of hundred individuals) living in limestone caves in Thailand and Burma (Myanmar). Little is known about their reproduction or ecology, but their teeth suggest an insectivorous diet. This species is rare, and due to its narrow range (their whole known range is 8 caves), and anthropogenic pressures on its habitat, is considered vulnerable by the IUCN.
To learn more: C. thonglongyai’s page in the Encyclopedia of life May 5, 2010 Kiwa hirsuta
K. hirsuta, also known as the Yeti crab, Yeti lobster or furry lobster, was discovered in 2005 living in near hydrothermal vents (around 7,200 feet deep) in the Pacific Ocean- 900 miles south of Easter Island in the South Pacific. This species is so unique in its morphology and genome that it was classified as the only known species in its (new) genus and (also new) family. The name “Kiwa” comes from the goddess of shellfish in Polynesian mythology. As is generally the case with species living in environments with little visible light, K. hirsuta lacks pigmentation and has very small eyes, which may be non-functional. Its most prominent morphological attribute is a large quantity of light-colored setae in its thoracic leg and claws, which are so abundant that it resembles fur (its discoverers described them as “extremely setose”). They are around 8 inches long and are observed at densities of 1-2 individuals per every 10 square meters of the basalt that surrounds hydrothermal vents. It was discovered by an international team diving on a research submarine. To learn more: E. Macpherson, W. Jones & M. Segonzac (2006). "A new squat lobster family of Galatheoidea (Crustacea, Decapoda, Anomura) from the hydrothermal vents of the Pacific-Antarctic Ridge". Zoosystema 27 (4): 709–723. April 27, 2010 Turtle epibiontsA diverse fauna lives on the surface of sea turtles. Many invertebrate species make their home on the skin, plastron (the ventral portion of a turtle’s shell), and carapace (the dorsal surface of the shell) of all known sea turtle species. These include several species of barnacles and crustaceans, and in some locations, turtles can host over a dozen different epibiont species. The term epibiont is used for species that use the turtles as a substrate only, and are considered to be generally harmless. External parasites or ectoparasites, on the other hand, take away some of the host’s resources and cause some level of damage (which can in some case be severe). Whether epibionts can cause damage to some individuals still needs to be researched. Ongoing research about turtle epibionts includes learning about their location on the turtle’s bodies and their genetic diversity. Scientists at the American Museum of Natural History’s Center for Biodiversity and Conservation have found that most of the green sea turtles they study at Palmyra Atoll have at least one epibiont species, including Gammarid and Tanaid crustaceans (see pictures below), and are working to identify them and learn more about their ecology and natural history.
To learn more: April 20, 2010 Tyrannobdella rexLeeches are annelids (worms whose bodies are segmented or formed by “rings”- anellus in Latin- a group also including earthworms) best known for feeding on blood, although not all species are haematophagous. Blood-feeding leeches attach to the body of a host (including humans) and feed until engorged, at which point they detach, normally causing little harm. Some leeches attach to body orifices, causing a condition known as orificial hirudiniasis. As part of their feeding strategy, they have evolved anesthetic and anticoagulant compounds in their saliva, some of which can have medical applications. Leeches are also used in reconstructive surgery and pain and wound management. A new genus and species of leech was described this week, after being found feeding in the nose of a nine year old girl in rural Peru, and later associated to three previous cases. This leech is unique because it has a single jaw with very large teeth. Phylogenetic analyses show that this new species belongs to a group of leeches specializing in feeding from the mucosal cavities of mammals, and this discovery has helped scientists understand the evolutionary origin of this very specialized feeding strategy.
This species was described by a team of scientists, including Anna Phillips, Alejandro Oceguera-Figueroa, and Mark Sidall from Leech Lab at the American Museum of Natural History. To learn more: April 5, 2010 Ophryotrocha craigsmithiThis week’s species is one of many that specialize in what is called whale-fall habitats. When a whale dies, its corpse drops to the bottom of the ocean where it becomes a resource to a wide variety of scavengers. A single whale corpse can host a diverse faunal community for many years. Worms in the genus Ophryotrocha are known to live in organically rich environments. They are polychaetes, a class of annelid worms characterized for having a pair of protrusions in each body segment, out of which many bristles (called chaete) grow. O. craigsmithi was found in a minke whale carcass off the coast of Sweden, and collected with a remotely-operated submersible vehicle. Although polychaetes are very common marine organisms, and the genus Ophryotrocha has been known for more than a century, O. craigsmithi was only discovered in 2009. The biodiversity in this genus, as in much of the deep ocean is still in need of further study. This species was named after Professor Craig R. Smith from University of Hawai`i at Manoa, who studies the ecology of marine sediments including whale-falls.
To learn more: http://www.mapress.com/zootaxa/2009/f/zt02228p056.pdf http://news.nationalgeographic.com/news/bigphotos/54045859.html March 30, 2010 Thermus aquaticusLast week’s species was an extremophile (an organism adapted to living in conditions that are not traditionally considered as life- supporting) adapted to life inside of cans of hair spray. This week’s species, Thermus aquaticus is a thermophile- it lives and thrives in very hot environments. T. aquaticus was discovered in the hot springs of the Lower Geyser Basin on Yellowstone National Park, can live in water as hot as 175°F (80°C). Themophilic organisms have been a source of novel molecules with important applications in biomedical research. T. aquaticus is best known for being the source of an enzyme that can copy DNA and is stable at high temperatures. This enzyme, called Taq polymerase is used in the polymerase chain reaction (PCR), a commonly used procedure in biochemical research and medicine. DNA strands separate from their normal coil structure when heated, making each strand “readable”. However, most enzymes do not work at those temperatures. The discovery of the Taq polymerase allowed for a laboratory procedure whereby DNA can be heated and copied. T. aquaticus and its relatives have also been the source of many other thermostable enzymes.
To learn more: Innis et al. 1988. DNA sequencing with Thermus aquaticus DNA polymerase and direct sequencing of polymerase chain reaction-amplified DNA. PNAS December 1, 1988 vol. 85 no. 24 9436-9440 March 23, 2010 Microbacterium hatanonisUp to now, the focus of “Species you didn’t know existed” had been on animals. We are still discovering new species, and learning about their ecology and behavior. Almost by any metric, we remain largely ignorant about the most basic information about most animal species, even those that are larger-bodied and terrestrial. It should then be no surprise that microbial biodiversity is still an important source of species we didn’t know existed. Some microbes are described as being “extremophiles”, meaning that they thrive in extreme environmental conditions. Our species of the week was discovered living inside cans of hairspray. It is an aerobic (uses oxygen) and rod-shaped bacterium that forms yellow colonies when cultured in the lab. Researchers found it to be sufficiently distinct in its genetic material, its morphology, physiology and metabolic requirements, to suggest it has had a distinct evolutionary history and is thus a species new to science. The study describing the species for the first time was only published in 2008, and little else is known about it. There is no evidence suggesting it has any negative effect on hairspray users.
Photo credit: Darby, Creg. Interactions with microbial pathogens. To learn more: March 16, 2010 CaeciliansAlthough resembling snakes or large earthworms, caecilians are in fact a group of amphibians, that is, they are most closely related to frogs and salamanders. They are blind or nearly blind, have no auditory openings, lack external limbs (and were once classified as belonging to the order Apoda, meaning without limbs), and have a distinct pattern of skin folds across their body, which contributes to their earthworm-like appearance. According to a new taxonomic revision by Dr. Darrel Frost (American Museum of Natural History) and collaborators, caecilians belong to the order Gymnophiona, and we currently know over 170 species belonging to 33 genera and 6 families. They have a pantropical distribution (but are absent from Madagascar), and are mostly oviparous (i.e. egg-laying) with aquatic larvae; some species however are ovoviviparous (i.e. the eggs remain in the mother’s body and the young are born live, although they develop in an egg). Mothers in one caecilian species, Boulengerula taitanus, form a thick and nutritious layer of skin cells from which the young feed (see this video). Caecilians tend to be burrowers and live inside networks of tunnels, but a few species are aquatic – their habitat preferences make them hard to see and study, and they remain among the least well-known major vertebrate group. Six caecilian species appear as having some level of threat in the IUCN Red List, but given our lack of knowledge about this group, this is likely an underestimation.
To learn more: Frost et al. (2006) The Amphibian Tree of Life. Bulletin of the American Museum of Natural History 297: 1-370 March 9, 2010 Saola (Pseudoryx nghetinhensis)Known to science only since a 1992 survey expedition to Vietnam, the saola is the first large mammal to be discovered since 1936- when the kouprey (Bos sauveli), a buffalo relative was discovered in nearby Cambodia. The saola belong to the Family Bovidae, which includes antelope, buffalo, bison, cattle, goats and sheep; however, it is the only known species in its genus. These large (adults weight about 90 kg and are about 150 cm in length) antelope-like creatures have distinctive facial markings, a black stripe extending from the shoulders, and a stripped tail. Both males and females have horns. The saola have a very restricted range and inhabit only in certain areas in 6 provinces in Vietnam and 3 in Lao PDR. Very little is known about this species’ ecology, reproduction or behavior. However, it is now listed as critically endangered due to habitat loss and hunting pressure. [Species suggested by Meg Domroese of the Center for Biodiversity and Conservation]
To learn more: http://www.panda.org/about_our_earth/species/saola/ http://www.eol.org/pages/2925803 Van Dung et al. 1993. A new species of living bovid from Vietnam. Nature 363, 443 - 445 (03 June 1993); doi:10.1038/363443a0 Kemp, N., M. Dilger, N. Burgess, C. Dung. 1997. The saola Pseudoryx nghetinhensis in Vietnam- new information on distribution and habitat preferences, and conservation needs. Oryx, 31/1: 37-44. March 2, 2010 Canthon aff. quadriguttatusDung beetles remove freshly deposited dung and eat it or use it to lay their eggs in dung “brood balls”. Dung removal results in a variety of important ecosystem functions including nutrient cycling, seed dispersal and control of pests and parasites. The Neotropics contain a large number of dung beetle species, even though Neotropical forests do not have abundant populations of large vertebrates to provide dung. As a result, Neotropical dung beetles have to compete intensely for dung, an ephemeral but irreplaceable resource. Scientists have discovered an unusual competition strategy in the Neotropical dung beetle Canthon aff. quadriguttatus (Olivier): they live attached to the tail or genital region of the primate species whose dung they use. By living on the monkeys, they are guaranteed quick access to their dung, to which they attach as it is being evacuated or immediately after. After consuming the dung, they climb back on the monkeys. From a distance, the presence of these beetle aggregations make the monkeys appear to have shiny objects around their tails. [Species suggested by Elizabeth Nichols of the Center for Biodiversity and Conservation]
Photo Credit: Jacobs et al. 2008. Neotrop Entomol 37(6):641-5.
Photo Credit: Jacobs et al. 2008. Neotrop Entomol 37(6):641-5.
Photo Credit: Jacobs et al. 2008. Neotrop Entomol 37(6):641-5. To learn more: Jacobs J, Nole I, Palminteri S, Ratcliffe B. 2008. First come, first serve: "sit and wait" behavior in dung beetles at the source of primate dung. Neotrop Entomol 37(6):641-5. Dung beetles help from the ground up The Scarabaeinae Research Network February 23, 2010 Tree kangaroos
Unlike their better-known relatives, tree kangaroos have hind and forelimbs of approximately the same size (this is what a normal kangaroo looks like). They also have long cylindrical tails, and are much smaller (adults are around 10-15 kilograms of body weight, depending on the species). All tree kangaroo species (10-14) belong to the Genus Dendrolagus- a word derived from the Greek words for “tree” and “hare”. They live in Papua New Guinea and Qeensland and most species spend the majority of their lives in trees (although some species are mainly terrestrial), coming down to the ground only occasionally. They are particularly agile in trees, where they are known to leap, jump and hop- but they spend as much as 60% of their time sleeping. Like all kangaroos, they are marsupials- females have pouches to carry the joeys. They are herbivorous and have complex stomachs with fermentation chambers, which enable them to process plant matter. Tree kangaroos have primitive immune systems, which make them quite susceptible to infection by the kinds of pathogens that cause tuberculosis in humans, and to immunosuppresion caused by stress. Of the 14 species listed by the IUCN list of threatened species, four are critically endangered, three are endangered and four are vulnerable, with habitat loss and hunting pressure listed as the main threats against them. To learn more: Dendrolagus - Encyclopedia of Life February 16, 2010 Furcifer labordi
Furcifer labordi, a species of chameleon from the arid regions of Madacasgar, has a unique life history: it spends most of its life in the egg as a maturing embryo. In fact, its entire lifespan (about a year) is shorter than the time it takes most other chameleon species to reach maturity- using current average life expectancy in the United States, if humans had this kind of life history, pregnancy would last around 52 years. F. labordi embryos develop inside the eggs for 8-9 months, after which follows growth and sexual maturation, courtship, mating and egg laying. Eggs hatch at the start of the rainy season in November. Hatchlings quickly grown into juveniles and by January, they reach sexual maturity. By February or March, females deposit the eggs, after which the entire adult population senesces and dies- this is the shortest lifespan ever recorded in a terapod (4-limbed vertebrates). The only time of the life cycle in which more than one age class is alive is the short period between egg laying and the time the adults die- for the rest of the time, the entire population is composed of one single cohort. Scientists know of no other species of terapod with this kind of life history, which is found in some ephemeral insects such as the mayflies. Because they are closely related to other chameleons that do not have this kind of life history, F. labordi can help us understand key aspects of the mechanisms responsible for aging and longevity. Dr. Christopher Raxworthy of the American Museum of Natural History is a co-author of a recent paper that describes F. labordi’s life history. To learn more:
Kristopher B. Karsten; Laza N. Andriamandimbiarisoa, Stanley F. Fox, and Christopher J. Raxworthy (2008-07-01). "A unique life history among tetrapods: An annual chameleon living mostly as an egg". Proceedings of the National Academy of Sciences 105 (26): 8980–8984. doi:10.1073/pnas.0802468105 February 9, 2010 Tardigrades
Tardigrades, also known as water bears or moss piglets, are a little-known phylum of microscopic animals containing about 1000 species- but it is estimated that as much as a few thousand species have yet to be described. They are widely distributed throughout the world and can be found in a variety of terrestrial, freshwater and marine environments, and are most commonly found in mosses and fresh water. Adults are tiny (0.5- 1.2 millimeters long), transparent and have four segments with 8 legs. They are reported to have a small and constant cell number and are famous for cryptobiosis: a dehydrated tardigrade (called a tun) can survive for years without water and can withstand extremely high pressure, radiation, high temperatures and freezing. Watch a video of a tardigrade walking, and click on the links below to learn more about tardigrades. To learn more: http://www.sciencefriday.com/videos/watch/10198 http://tardigrades.bio.unc.edu/ |
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