Provanna dongshaensis: A new species of fossil Gastropod from hydrate-bearing sediments in the South China Sea.

The Abyssochrysoidea are a large group of Caenogastropods found in deep-sea environments. The genus Provanna is the largest within this group, currently containing 29 extant species from  hydrothermal vents, hydrocarbon seeps, and organic falls (such as sunken wood and Whale falls) in the Pacific Ocean, the Caribbean, the Southern Ocean, and off the west coast of Africa, as well as nine species from preserved seep deposits and organic falls in Japan, New Zealand, the United States, and Peru, the oldest of which date back to the Cretaceous. These Snails are grazers and detritivores form part of biological communities which are dependent on the chemosynthetic activities of Bacteria and Archaeans for their survival.

In a paper published in the journal Zoosystematics and Evolution on 2 January 2024, Cong Wu and Fang Chen of the National Engineering Research Center of Gas Hydrate Exploration and Development, the Key Laboratory of Marine Mineral Resources of the Ministry of Land and Resources, and the Guangzhou Marine Geological Survey, Ying Tian of the Key Laboratory of Mariculture and Stock Enhancement in North China Sea at Dalian Ocean University, and the Dalian Shell Museum, Kazutaka Amano of the Department of Geology and Paleontology at the Japanese National Museum of Nature and Science, and Xin Su of the School of Ocean Sciences from the China University of Geosciences, describe a new species of Provanna from specimens recovered from two drill cores sunk into cold seeps in the South China Sea.

The new species is described from two specimens, and three other shell fragments, recovered from two separate drill cores (GMGS2-09B and GMGS2-07B) sunk into the seafloor of the northern South China Sea. The shells were obtained from carbonate layers with carbon isotope signatures which strongly indicate that they were laid down at ancient methane seeps. The new species is named Provanna dongshaensis, where 'dongshaensis' means 'from Dongsha' in reference to the island known as 'Dongsha' in Chinese, which lends its name to the area where the fossils were found. This island is currently administered by Taiwan under the name 'Tungsha', and is known as 'Pratas Island' in English.

Global distribution of genus Provanna displayed as type locations of known species and location of the study (GMGS2-07B and GMGS2-09B). orange circle: active hydrothermal vents, hydrocarbon seeps where extant Provanna species are discovered; blue circle: seep deposits or organic falls that yield fossil Provanna. Wu et al. (2025).

The larger of the two specimens of Provanna dongshaensis is 10.89 mm high and has a final whorl width of 7.13 mm; the smaller has a height of 7.80 mm and a final whorl width of 5.02 mm. It is not possible to tell the length of the original shells as both are slightly damaged and lack their tips. This means that the protoconch (the shell that a marine Gastropod uses during its larval, planktonic stage), an important diagnostic tool for Gastropods is missing. Nor is the radula (tongue), another key diagnostic feature, present in any specimens, nor any genetic organic material from which DNA could be extracted. Previous studies, however, have established that the shell microstructure of the genus Provanna, is distinctive, so Wu et al. are confident in their assignment of the shells.

Provanna dongshaensis, from a late Pleistocene seep site in the northern South China Sea. (A)–(C) Holotype, GMGS2-09B-C15-2, specimen from core 09B-4, shell height: 7.8mm; (D)–(F) Paratype, GMGS2-07B-A1, specimen from core 07B-2H-2A with the protoconch almost lost, shell height: 10.89mm; (G)–(I) Incomplete specimen GMGS2-09B-C15-1 from core 09B-2M-1A; (J)–(L) Incomplete specimen GMGS2-09B-C14 from core 09B-4. (M)-(O) Incomplete specimen GMGS2-09B-C13 from core 09B-2M-1A. Scale bar is 5 mm. Wu et al. (2025).

The largest of the specimens in the collection has been dated to 91 693 yeats before the present, though all others are significantly younger, with dates of 16 230±50 years before the present and 15120±50 years before the present. This places all specimens within the final Pleistocene glaciation, although their chronological distribution is probably more closely linked to the life cycle of the cold methane seep where they lived than to the climate on the surface. Wu et al. note that a number of other Gastropod shells are present in the cores from which Provanna dongshaensis was derived, suggesting that the site might be significant for our understanding of ancient cold seeps in the South China Sea.

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Five new species of Staircase Snails from Borneo.

Staircase Snails, Diplommatinidae, are small terrestrial Gastropods with operculi, which get their common name from the strong ribbing on their shells, which can resemble a spiral staircase. They are members of the Cyclophoroidea, a group of Caenogastropods which have lost their combed gills and developed an internal lung independently of the Pulmonata.

In a paper published in the journal Folia Malacologia, Jaap Vermeulen of JK Art and Science and Mohd Zacaery Khalik of the Faculty of Resource Science and Technology at Universiti Malaysia Sarawak, describe five new species of Staircase Snails from Borneo.

The first new species described is placed in the genus Arinia, and given the specific name bathyodon, meaning 'deep-tooth'. The species is described from a collection of shells gathered on a limestone plateau in a primary rainforest Sangkulirang Peninsula in the Indonesian province of Kalimantan. These shells are 1.2-1.6 mm high, 0.75-0.90 mm wide, and ellipsoid-cylindrical to almost cylindrical in shape, with the last two whorls widest in frontal view. The whorls are convex, and there is a constriction of the shell before the aperture, which lacks teeth. The radial ribs are single-crested, and there are 8-12 per 0.5 mm. 

 

Arinia bathyodon: (1) Holotype, frontal view, shell height 1.6 mm; (2) same shell, right lateral view; (3) same shell, umbilical view; (4) paratype, right lateral view with part of the shell wall removed to show internal tooth. Vermeulen & Khalik (2022).

The second new species is also placed within the genus Arinia, and given the specific name congener, meaning 'of the same kind', in reference to the fact that it closely resembles the previously described Arinia similis, which is found in the same area. The species is described from a series of shells collected in the Gunung Mulu National Park in Sarawak Province, Borneo, on the path between Clearwater Cave and Moonmilk Cave. These shells are 1.0-1.2 mm in height, 0.75-0.80 mm in width, and shortly ellipsoid-cylindrical in shape, with the body whorl or last two whorls widest in frontal view. There is a constriction before the aperture, which lacks teeth. The earlier parts of the shell have 12-17 ribs per 0.5 mm, which drops to 5-7 ribs per 0.5 mm after the second half of penultimate whorl.

 

Arinia congener: (5) holotype, frontal view, shell height 1.2 mm; (6) same shell, right lateral view; (7) same shell, umbilical view. Vermeulen & Khalik (2022).

The third new species is again placed in the genus Arinia, and given the specific name semiconica, meaning 'half-cone-shaped', in reference to the shape of the shells. The species is described from a series of specimens collected at Kampong Air Putih near Samarinda, and at Gua Ambulabung in the Baay river valley on the Sangkulirang peninsula, with both localities being in Kalimantan. These shells are 1.7-2.3 mm high, 1.45-1.70 mm wide, and conical with almost flat sides, with the body whorl widest in frontal view. The whorls are convex, with the body whorl often slightly more narrowly rounded at the periphery. A constriction is present before the aperture, which lacks teeth. The ribs are single-crested with 3-6 ribs per 0.5 mm.

 

Arinia semiconica:(8) Holotype, frontal view, shell height 1.8 mm; (9) same shell, right lateral view; (10) same shell, umbilical view. Arrows indicate the position of the constrictions. Vermeulen & Khalik (2022).

The fourth new species is placed in the genus Notharinia, and given the specific name xenos, meaning 'foreigner', in reference to the fact that the genus Notharinia has previously only been identified from Laos and Cambodia, locations significantly distant from Borneo. Vermeulen and Khalik note that the genus Notharinia is similar to the genus Arinia, differing mainly in the constriction of the shell before the aperture of adult shells of Arinia, which is absent in Notharinia; something which could potentially have been lost separately in Notharinia xenos, thereby making the genus paraphyletic, but in the absence of genetic data they choose to base their diagnosis upon the available morphological data.

Notharinia xenos is described from six shells collected from limestone scarps in the upper Tatau river valley of Sarawak State Malaysia. These are 1.9-2.4 mm high and 0.85-0.90 mm wide, with cylindrical shells, slightly widened towards the base. The whorls are moderately convex, the ribs single crested and there are 8-15 ribs per 0.5 mm.

 

Notharinia xenos: (11) Holotype, frontal view, shell height 1.9 mm; (12) same shell, right lateral view; (13) same shell, umbilical view. Vermeulen & Khalik (2022).

The final new species is placed in the genus Opisthostoma, and given the specific name hemituba, meaning 'half-trumpet' in reference to the shortened shells of this species. The species is described from a series of shells collected at Gua Mardua near Kampong Pengadan on the Sangkulirang Peninsula of Kalimantan Province, Indonesia. These range from 1.6 mm to 1.7 mm in height and from 1.60 mm to 1.75 mm in width, and are shortly cylindrical to depressed conical, with the body whorl widest in frontal view. The apex of the shell is oblique and truncated. The whorls are moderately convex, and rounded, the  body whorl is rather narrowly rounded at the base, towards a constriction before the aperture. The ribs are low and thin, being widely spaced; on the spire there are 3-5 ribs per 0.5 mm, on the body whorl this drops to 2-3 ribs per 0.5 mm.

 

Opisthostoma hemituba. (14) Holotype, frontal view, shell height 1.6 mm; (15) same shell, right lateral view; (16) same shell, umbilical view. Arrows indicate the position of the constrictions. Vermeulen & Khalik (2022).

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Erhaia norbui: A new species of freshwater Snail from Bhutan.

Gastropods of the genus Erhaia are small aquatic Snails with ovoid shells less than 5 mm high, single gills and opercula, found in clear freshwater environments across a broad area of northern India, Nepal, Bhutan, and eastern China, with a total east-west distribution range of about 3500 km. These Snails are usually found in springs and brooklets, and show a high rate of endemism, with many species only known from a limited area or even single location. To date, three members of this genus have been described from Bhutan, two of which are found at single locations in Latipur and Kavre districts, with the third found at both of these locations, plus a further four localities.

In a paper published in the journal ZooKeys on 2 February 2022, Edmund Gittenberger of the Naturalis Biodiversity Center, and GiMaRIS, Choki Gyeltshen of the National Biodiversity Centre of Bhutan, and Björn Stelbrink of the Department of Animal Ecology & Systematics at Justus Liebig University Giessen, describe a new species of Erhaia from Haa District in Bhutan.

The new species is named Erhaia norbui in honour of Sangay Norbu, who discovered the population from which the species is described. The description is based upon six shells, collected from a spring at an altitude of 2700 m above sealevel, close to the village of Naychu. 

 

Erhaia norbui from the type locality, district Haa, Uesu, Naychu, roughly 2700 m above sealevel. (3) Holotype, NBCB 1239 (height 2.3 mm) and paratypes used for DNA analyses (4 UGSB 25956,height 1.5 mm 5 UGSB 25957, height 1.8 mm). Scale bar is 1 mm. Gittenberger et al. (2022).

Erhaia norbui has a ovoid to elongate ovoid or conical shell, smooth or with spiral microsculpture on the proto- and/or teleoconch (the protoconch is the embryonic shell of a Snail, which remains attached to the later shell, or teleoconch, and is often quite different in structure, making it a useful taxonomic tool). The apex of the shell is conspicuously and obliquely flattened. The aperture of the shell varies from ovoid-elliptical to circular; its palatal side is curved and gradually passes into the basal side. The peristome (layer of skin covering the shell is continuous, attached at the parietal side or slightly protruding. The umbilicus (gap inside the spirals of some Snail shells) is minute or closed. The parietal part of the aperture is smooth or with a lamella; columella smooth or with 2 spiral lamellae.

 

Habitat of Erhaia norbui at the type locality. Sangay Norbu in Gittenberger et al. (2022).

A DNA analysis based upon mitochondrial markers, plus the gened which code for the cytochrome c oxidase I protein and 16S rRNA, established that Erhaia norbui is a separate species, genetically differentiated from all other Erhaia species, but also that the three Erhaia species which are found in Bhutan and which were included in the study, form a distinct clade, all being more closely related to one another than any of them is to any species found outside the kingdom.

 

Maximum likelihood tree reconstructed with RAxML BlackBox (GTR+G substitution model for each partition and 100 bootstrap replicates), with new data in red. Numbers on branches denote bootstrap values of more than 50. Gittenberger et al. (2022).

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Craspedotropis gretathunbergae: A new species of terrestrial Caenogastropod from the Kuala Belalong rainforest of Brunei

Although Mollusca is, after Arthropoda, the second-most species-rich animal phylum on land (at least in terms of described species), their species numbers are only moderately high compared with the Arthropods. Even in hyperdiverse forested regions in the humid tropics, such as northern Borneo, the numbers of known species are in the hundreds, not thousands and trends of discovery appear to be levelling off towards the true number of species. This means that, with relatively little fieldwork effort, it is possible to obtain a more or less complete inventory of the terrestrial malacofauna of a certain area. 

In a paper published in the Biodiversity Data Journal on 20 February 2020, a team of taxonomic experts and lay people led by Menno Schilthuizen of Taxon Expeditions, the Naturalis Biodiversity Center, Universiti Malaysia Sabah, and the Faculty of Science & Institute for Biodiversity and Environmental Research at University Brunei Darussalam, describe a new species of terrestrial Caenogastropod discovered during a citizen science project in the Kuala Belalong rainforest of Brunei Darussalam (Borneo).

Schilthuizen et al. are using field courses to several biodiversity hotspots in the world for such a purpose and they use the term 'taxon expeditions' for this. Taxon expeditions are a new concept in which a group of taxonomic experts and lay people work together in a hybrid work form of field course and biodiversity discovery expedition to discover unknown species from a given area. On their annual taxon expedition to the Ulu Temburong lowland rainforest in Brunei Darussalam, surveys of terrestrial snails have so far yielded over 25 species. The expected diversity for this type of forest would be around 85 species, but already our inventories are turning up previously unknown species.

Schilthuizen et al. describe a new species from the large Caenogastropod family Cyclophoridae. In the Southeast Asian tropics, non-Stylommatophora (i.e. Neritopsina and Caenogastropoda, not Pulmonates, the most common and familiar group of terrestrial Gastropods) comprise nearly half of the total malacofauna. These Snails are, however, more sensitive to habitat disturbance than the Stylommatophora. Studies of  malacofauna conservation biology on limestone hills in Sabah have previously shown that these non-Stylommatophora groups are the first to disappear after forest degradation, presumably as a result of lower tolerance ranges for temperature and humidity.

The description of the new Cyclophorid is the concerted effort of untrained ‘citizen scientists’ working together in a field lab. The specific epithet was decided upon during a voting session, in which participants could suggest and vote for scientific names.

Schilthuizen et al. collected living snails by hand, at night, amongst vegetation along the left (south) bank of the Belalong river, 50 m downstream of Kuala Belalong Field Studies Centre. Specimens were sorted to putative morphospecies and then further examined morphologically with a dissection microscope with 10× and 20× eye pieces. Photographs and video were made either with a smartphone through the eyepiece of a microscope or on a translucent white acrylic sheet with a Nikon D800e fitted with a Laowa 25 mm ultra-macro lens. Drawings were made based on the photographs. Specimens were deposited in the collection of the University of Brunei Darussalam Museum.

The new species is placed in the genus Craspedotropis, and given the specific name gretathunbergae, in hounour of the young climate activist Greta Thunberg, because Caenogastropod Microsnails from tropical rainforests, like this new species, are very sensitive to the droughts and temperature extremes that are likely to be more frequent as climate change continues. Via mutual contacts, Schilthuizen et al. approached Ms. Thunberg and learned that she would be 'delighted' to have this species named after her.

The protoconch (the larval shell of a Snail, which forms the tip of the adult shell) lacks distinct sculpture and the juncture with the teleoconch (adult shell) not visible. The spire of the shell is highly conical, consisting of 5.25 to 5.75 convex whorls, The radial sculpture comprises growth lines and densely placed riblets (30-70 per mm on the body whorl), while the spiral sculpture comprises 4 high, prominent, here and there somewhat crenellated radial ribs, which start after 1.5 to 2.0 whorls. The first spiral rib (from the top) is located between the periphery and the suture with the previous whorl. The second sits at the periphery. The third is located near the suture with the next whorl and is visible on the body whorl in some, but not all, individuals. The fourth is located on the basal side and only visible on the edge of the umbilicus. Between the ribs are fine spiral lines. The umbilicus (gap between the whorls, seen on the underside of an upturned shell) is wide, without additional spiral ribs.

Craspedotropis gretathunbergae, shell in apertural view. Pierre Escoubas in Schilthuizen et al. (2020).

The aperture of the shell is slightly wider than high, the peristome (shell around the apature) slightly thickened, with angularities coinciding with the four spiral ribs, but without sinuosities; the basal side is horizontal. The apature is 0.86 - 0.90 mm high and 0.92 - 0.97 mm wide. The peristome carries about 10 tightly packed accretions, coloured dark brown because of the thickened periostracum (thin organic coating or 'skin' of the shell).

Craspedotropis gretathunbergae. (a) Shell with operculum in apertural view. (b) Detail of the body whorl in lateral view. (c) Detail of the shell in umbilical view. Schilthuizen et al. (2020).

The operculum ('lid' used to seal the shell) is thin and horn-like. The whorl margins not raised but flattened into a smooth concave dish, of which the outer part is greenish-brown (presumably because of a thickly applied periostracum), the central part nearly clear. No calcareous matter visible.

The species is known only from the Ulu Temburong lowland rainforest of Temburong District in Brunei Darussalam. It is found in tropical mixed Dipterocarp lowland rainforest. All individuals were found alive at the foot of a steep hill-slope, next to a river bank, foraging at night on the upper surfaces of green leaves of understorey plants, up to 1 m above ground level.

Active individual of Craspedotropis gretathunbergae. Pierre Escoubas in Schilthuizen et al. (2020).

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Fluminicola umpquaensis & Fluminicola fresti: Two new species of Pebblesnail from Oregon.

Pebblesnails, Fluminicola spp., are small globose to conical freshwater Snails found in the watersheds of western North America from California to British Colombia. The Snails inhabit a range of habitats from small seeps and springs to large rivers and lakes, with the group thought to contain many species, each with a limited range and specific habitat requirements. Despite this, only twenty-five species have been described to date, fourteen of which come from the Sacramento River Basin and six from the Columbia River Basin, with many other known populations that have historically been grouped into a small number of widespread populations, something which is now believed to be erroneous. Many populations of Pebblesnails are thought to be at risk due to Human activities, and gaining a proper understanding of their taxonomy is crucial before any legal protection for these species can be gained.

In a paper published in the journal ZooKeys on 8 June 2017, Robert Hershler of the Department of Invertebrate Zoology at the Smithsonian Institution, and Hsiu-Ping Liu and Niko Hubbart of the Department of Biology at the Metropolitan State University of Denver, describe two new species of Pebblesnails from the Umpqua and Rogue River Basins in Oregon.

Hershler et al. carried out gene sequencing and morphometric analysis of 161 Pebblesnails from 35 sites in the Umpqua and Rogue River basins. From this they were able to detect three distinct clades of Pebblesnails. One of these was identified as a new population of Fluminicola multifarius, a species previously known from the Sacramento and McCloud river basins in California. The distribution of this species is now extended to include the southern part of the upper Rogue River Basin. This also raises the possibility that the species might be found in the Klamath River Basin, which lies between the Sacramento and Rogue basins, and where the species has not yet been recorded. The remaining two populations are described as new species. 

Shells, opercula and radula, Fluminicola multifarius from the Rogue River Basin in Oregon. (A) Shell. (B) Shell. (C) Shell. (D), (E) Opercula (outer, inner sides). (F) Portion of radular ribbon. (G) Central teeth. (H) Lateral teeth. Scale bars: (A)–(B) 1.0 mm; (D)–(E) 250 μm; (F), 100 μm; (G)–(H) 10 μm. Hershler et al. (2017).

The first new species is named Fluminicola fresti in honour of the late Terrence Frest, for his contributions to the study of malacology in the northwestern United States. This species was found in spring-fed environments in the upper parts of both river basins, to the north of Little Butte Creek. The species is small to medium sized for the genus, reaching 2.3 to 5.5 mm in height, with a trochoidal to ovate-conic shell, 3.5-4 whorls when fully grown and an ovate aperture. 

Shells, opercula and radula, Fluminicola fresti. (A) Holotype. (B), (C) Sympatric ovate-conic and trochiform shell morphs, respectively. (D) Shell. (E), (F) Opercula (outer, inner sides). (G) Portion of radular ribbon. (H) Central teeth. (I) Lateral teeth. Scale bars: (A)–(D) 1.0 mm; (E)–(F) 250 μm; (G) 100 μm; (H)–(I) 20 μm. Hershler et al. (2017).

The second new species is named Fluminicola umpquaensis, meaning ‘from Umpqua’, the species being widely distributed in the Umpqua River Basin but not known from elsewhere. The species is large for the genus, reaching 9.5 mm in height, with a conical and a spire that tends to erode, leaving it with somewhere over 3.5 whorls when mature. The species was found in springs, streams and rivers in the Umpqua Basin.

Shells, opercula and radula, Fluminicola umpquaensis. (A) Holotype. (B) Shell. (C) Shell. (D), (E) Opercula (outer, inner sides). (F) Portion of radular ribbon. (G) Central teeth. (H) Lateral teeth. Scale bars: (A)–(E), 1.0 mm; (F), 100 μm; (G)–(H), 10 μm. Hershler et al. (2017). 

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Tryonia infernalis: A new species of Cochliopid Snail from a hot spring in the southern Nevada Desert.

The deserts of southeast California and southwest Nevada have been shown to host a distinctive fauna of endemic (found nowhere else) Caenogastropod Snails, with many species with very limited distributions belonging to the families Assimineidae, Cochliopidae and Hydrobiidae found along tributaries to the Great Basin and lower Colorado Rivers and in the many hot springs found across the area.

In a paper published in the journal ZooKeys on 30 March 2015, RobertHershler of the Department of Invertebrate Zoology at the Smithsonian Institution and Hsiu-Ping Liu and Jeffrey Simpson of the Department of Biology at the Metropolitan State University of Denver describe a new species of Cochliopid Snail from Blue Point Spring, a hot spring close to Lake Mead in Clark County, southern Nevada.

The new Snail is placed in the genus Tryonia and given the specific name infernalis, meaning ‘hellish’, in reference to the proximity of Blue Point Spring to Nevada’s Valley of Fire. Tryonia infernalisis described from over 200 specimens ranging in length from 2.41 mm to 3.09 mm in shell height, with between 5 and 5¾ whorls. The males are on average slightly smaller than the females. The shells of the Snails are light brown, the bodies darker.

Tryonia infernalis, (A) female shell, (B) male shell, (C, D) opercula (outer, inner sides). Scale bars (A, B): 1.0 mm; (C, D): 200 μm. Hershler et al. (2015).

The species is known only from close to the source of Blue Point Springs, in waters within about 10 m of the spring from which the waters issue, which have a temperature of about 30˚C. The Snails were first observed in 1988, but appeared to have gone extinct in 2002. However they reappeared in 2007 and are now locally abundant.

Photographs of Blue Point Spring. (A) Outflow channel; spring originates below one of the mesquite trees in the upper right (photograph taken on 24 March 2009). (B) Ponded area where Tryonia infernalis occurs abundantly; the USGS gage house is in the lower left (15 May 2014). Hershler et al. (2015).

A genetic study of Tryonia infernalis suggests that it is most closely related to Tryonia clathrata, a species known from the White River Valley, which drains into Lake Mead, via the Muddy River, a few kilometres up-flow from Blue Point Spring. Two other Snail species present at the spring, Pyrgulopsis coloradensis and Assiminea sp., as well as a species of Amphipod Crustacean, Hyalella sp., appear to be more closely related to species from Death Valley in California, roughly 200 km to the west, and on the other side of the Spring Mountains.

Map showing the location of Blue Point Spring relative to other geographic areas. The collecting localities for specimens of Pyrgulopsis sanchezi and Tryonia clathrata (sister taxa of Blue Point Spring endemics) used in the molecular phylogenetic analyses are also shown. Hershler et al. (2015).

A molecular clock analysis of the three Snail species suggests that Assiminea sp. diverged from its closest known relative 1.42-1.60 million years ago, Tryonia infernalis from its nearest known relative 2.14-2.41 million years ago and Pyrgulopsis coloradensis from its closest relative 2.46-2.78 million years ago, suggesting that in all cases divergence occurred during the Pleistocene.The age of Blue Point Spring is not known, but the oldest spring deposits showing evidence of groundwater discharge associated with it are thought to be at least 2.6 million years old (Early to Middle Pleistocene). At no point during this time has Blue Point Spring or the surrounding area shared a common watershed with Death Valley, so Hershler et al. suggest that they may have been transferred to the site by Birds (which is thought to be common in for small invertebrates).

Hershler et al. suggest that Blue Point Spring represents a unique, if tiny, biodiversity hotspot with at least two (and possibly three) endemic Snail species. The site is currently administered by the National Park Service as part of the Lake Mead National Recreation Area, but Hershler et al. believe that it is in need of extra protective measures to ensure the survival of its unique fauna. The site is currently located close to a paved highway and small parking area, which makes it liable to disturbance by foot traffic and other activities. The Snail population might benefit from fencing off the spring, but the site is also home to one of the few known populations of the Relict Leopard Frog, Rana onca, which is known to be adversely affected by fencing, ruling this option out. Blue Point Spring was also used as an exotic-fish rearing site for the aquarium trade until the mid-1950s, and is known to host a population of the Convict Cichlid, Amatitlania nigrofasciata, which is omnivorous and may present a threat to the Snails, as well as the Red-rimmed Melania, Melanoides tuberculata, a highly invasive Gastropod species which has been shown to have an adverse effect on endemic Snail populations at other southwest American spring sites.

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The role of aquatic polymers in transmitting disease in coastal ecosystems.

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