#lake invertebrates

[uncharismatic-fauna]

A Dive into the Diving Spider

The diving spider, or water spider (Argyroneta aquatica) is perhaps one of the most unique arachnid species on Earth, noted for living almost entire life completely underwater. This species is found throughout northern Europe and Asia in clear freshwater ponds, lakes, wetlands, and slow-moving rivers with lots of aquatic vegetation.

Like other spiders, the water spider does breathe air. When submerged, specialized hydrophobic hairs create an air bubble attached to its abdomen, which allows the spider to store oxygen while moving around underwater. In addition, these spiders build a web known as diving-bell webs. These webs, constructed of spider silk, are constructed underwater, and supplied with air bubbles from the surface. A. aquatica spends most of its time in these webs, leaving only to replenish its air supply-- about once every 24 hours-- or to find prey.

The diving bell spider's prey are, unsurprisingly, primarily insects. In particular they feed on water fleas, aquatic isopods, insect larvae, and small crustaceans like shrimp. Individuals catch their prey by hiding inside their webs until prey trips one of the trip-wires constructed in the surrounding vegetation. They then surge out, seize their prey, and drag it back into the air-filled web where the spider can digest it. Predators of water spiders include aquatic beetles, dragonfly larvae, and frogs. Fish can also predate upon water spiders, but they are usually scarce due to the low aquatic oxygen environment in which the spiders live.

Ordinarily, A. aquatica is a fairly plain, brown spider. Males are slightly larger than females; 18.7 mm (0.74 in) to their 13.1 mm (0.51 in) in length; this is a rare phenomenon in spiders, as females are typically larger. Males also have a longer pair of front legs. However, females were found to construct much larger nests, as they must also provide space for their eggs and young.

When a male is ready to mate, which occurs during spring, he will construct several sperm packages that he holds in his palps, or mouth appendages, while he seeks out potential mates. If he finds a receptive mate, the two will engage in a swimming ritual around her web before he gives her one of his sperm packages. Afterwards, the female constructs a sac with 50-100 eggs; she may do this up to 6 times throughout a single year. The eggs hatch 3-4 weeks after laying, and the offspring remain in the nest for another 2-4 weeks. Individuals typically become sexually mature not long after, and may live up to 2 years in the wild.

The water spider can deliver a painful bite, with symptoms of inflammation, vomiting, and fever lasting 5-10 days. However, the bite is not known to be fatal to humans.

Conservation status: The diving bell spider has not been evaluated by the IUCN. The primary threat is likely habitat destruction, although at least one area in South Korea has been designated specifically as protected habitat for the species.

Want to request an uncharismatic critter? Just send me proof of donation to any of these vetted fundraisers for Palestinian refugees!

Photos

Stephan Hetz

[unkn0wnvariable]

Banded Demoiselle

A banded demoiselle damselfly perched on top of a grass flower, at RSPB Fen Drayton Lakes.

[magicmetalblog]

InsertAnInvert2024

Carcinization week 3: not a crab

Lake Baikal amphipod (acanthogammarus victorii)

[elntangle]

I guess if twitter's going down or becoming worse, I might as well start posting my natural history-inspired art here more just in case. Maybe I'll upload a backlog of things. Here's my last sketchbook drawings of last year.

[sadboygrim]

Blue 🦀

[billionneuronscurious]

A Palm Sized Mollusc.

I was reminded of my BSc Zoology Experiment and Dissection of 'Pila', after watching this palm sized huge Mollusc, found in a lake.

[krystal-prisms]

My invertebrates prof - some of these flat worms can get to be pretty big. One of the longest turbellaria worms ever found was in Lake Baikal if you know where that is

Me- there's always something new with this fucking lake

[herptilesandher]

A fresh shed from a wild crayfish!

[gabimedia]

Seagulls on Lake Bucov by Vasiliu Gabriel Via Flickr: Seagulls on Lake Bucov

[yellosnacc]

Once again a creature from the continent of Slomen. A very primitive but also very specilised critter. 6 to 30 cm long, wet roots up to 45cm.

They live in many aquatic environments but most often you will find them in forest rivers and lakes. Some species have even adapted for life in the sea and could be considered fully aquatic while still air breathing.

Majority of the clade feeds on small animals like invertebrates sometimes parts of plants they can digest. Their hunting strategy is either burst swimming, jumping or just sliding on top of some slow prey.

There were two important species that started life on land, with the leaf ancestor being a smaller, less land specilised of the two. Leafs are one of their earliest evolutionary branches as land vertebrates and have retained many acient features like paw suckers and teeth instead of claws. In bigger vertebrates most of these little teeth were lost and became true claws or fingers (even present on the other land climber ancestor).

They can actually eat with their feet that are still closely connected to their stomach. But it applies only to very small food particles.

The wets are not very culturally significant but some regions do eat them. But the thick mantle isn't very tasty. In some places they symbolise good harvest season.

These little guys are also related to the 'birds' of Elve and I'm sure you can see why.

[todaysbird]

the common shelduck is a migratory duck largely found in eurosiberia. males and females look similar, but males have sharper coloration and lack white markings on the face that are present in females. the species primarily feeds on small invertebrates such as crabs and grasses. during the breeding season, the species is largely found around lakes and rivers; their nests are often made in unusual locations such as rabbit burrows and haystacks.

[uncharismatic-fauna]

The Stupendous Alligator Snapping Turtle

Alligator snapping turtles (Macrochelys temminkii) are one of three recognised species of snapping turtle, all of which are found in North America. This particular species is found in the southeastern United States and the Mississippi Basin in particular. Macrochelys temminkii prefers deep freshwater, and is especially common in deep rivers, wetlands, and lakes.

The alligator snapping turtle is the largest freshwater turtle in North America, and is one of the heaviest in the world. Most individuals weigh between 70-80 kg (154-176 lbs), and are about 79-101 cm (31-39 in) long. However, the largest verified indiviual weighed over 113 kg (249 lb), and many others have been recorded in excess of 100 kg. The species is easily identifiable by its large, boxy head and thick shell with three rows of raised spikes. Typical alligator snapping urtles are solid black, brown, or olive green, though the shells of many older individuals can be covered in green algae.

M. temminkii is famous for its strong bite, which is most often utilised when feeding. The turtle's tongue resembles a worm, and at night individuals lie on the bottom of the river or lake bed with their mouths open. Fish are enticed by the bait-tongue, and when they get close enough the alligator snapping turtle's mouth clamps down around them. In addition to fish, this species may also feed on amphibians, invertebrates, small mammals, water birds, other turtles, and even juvenile alligators where their territories overlap. The alligator snapping turtle's relies on ambush techniques, and so hunters can remain submerged for up to 40 minutes. In some cases, individuals can also 'taste' the water to detect neaby mud and musk turtles. Because of this species' thick shell and ferocious bite, adults have few predators, but eggs and hatchlings may fall prey to raccoons, predatory fish, and large birds.

This species spends most of its time in the water, only emerging to nest or find a new home if their current habitat becomes unsuitable. Mating occurs between Februrary and May, starting later in the northern regions of the species' range. Males and females seek each other out, but generally don't travel great distances. About two months after mating, females dig a nest near a body of water and deposit between 10-50 eggs. Incubation takes up to 140 days, and the average temperature of the nest determines the sex of the hatchings; the hotter it is, the more males are produced. In the fall, hatchings emerge and are left to fend for themselves. Sexual maturity is reached at between 11 and 13 years of age, and individuals can live as old as 45 years in the wild.

Conservation status: The alligator snapping turtle is listed as Vulnerable by the IUCN. The species is threatened by overharvesting for meat and for the pet trade, and by habitat destruction.

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Photos

Ed Godfrey

Cindy Hayes

Eva Kwiatek

Nathan Patee

[unkn0wnvariable]

Wasp Beetle

A wasp beetle sunbathing on a reed stem, at RSPB Fen Drayton Lakes.

[herpsandbirds]

Do you have any cool facts about Missouri wildlife?

I'd love to share something with my Midwestern friends, and thank you for always updating this blog!

I don't know if i have any Missouri animal facts per se... but I can share some of the state symbols with everyone.

We moved around a lot when we first came to the U.S. and we lived briefly in Kansas City. I have great memories of going to the Ozarks at Christmas time (near Lake of the Ozarks). I specifically remember following woodpeckers and deer around the forest in the snow.

SOME MISSOURI STATE SYMBOLS:

STATE BIRD: Eastern Bluebird (Sialia sialis), family Turdidae, order Passeriformes, found across much of the central and Eastern U.S., SE Canada, and NW Mexico

Changes in land use lead to drastic declines in Eastern Bluebirds after the early 1900s. They have recovered in many places, due to "bluebird trails", reestablishing appropriate habitat and nest box campaigns for public and private property.

Find out more: NestWatch | Eastern Bluebird - NestWatch

Blue birds are in the thrush family, Turdidae, along with American Robins.

They eat mainly worms, insects, and other small invertebrates (but also take berries for part of the year).

Bluebirds are cavity nesters, nesting in tree holes usually, but will readily take to properly constructed and placed nest boxes.

Males (pictured) are brighter blue, and females are a more muted and faded blue or bluish gray.

photograph by Keith Kennedy

STATE AQUATIC ANIMAL: American Paddlefish (Polyodon spathula), family Polyodontidae, order Acipenseriformes, found in various parts of the Mississippi River basin

This species is the only member of this family that still exists. They are most closely related to sturgeons. This order, Acipenseriformes, is considered one of the most evolutionarily primitive groups of ray finned fishes.

They do not have scales, and their skeleton is mostly cartilaginous.

They are filter feeders. Their heads and rostrums are covered with thousands of sensory receptors, which help them locate zooplankton swarms.

They are considered "vulnerable" due to overfishing, habitat degradation and destruction, and pollution.

photograph via: US Fish & Wildlife Service

STATE ENDANGERED ANIMAL: Eastern Hellbender (Cryptobranchus alleganiensis), family Cryptobranchidae, eastern United States

The largest salamander in the Americas, it grows to a total maximum length of up to 40 cm (15.7 in). 

Though nationally it is considered to be just "vulnerable", in some states (like Missouri), it is "endangered".

photograph by Mark Tegges

STATE REPTILE: Three-toed Box Turtle (Terrapene triunguis), family Emydidae, found in the South-central and Southeastern U.S.

This specie shas been considered to be a subspecies of the Eastern Box Turtle, T. carolina (and still is by some herpetologists).

These turtles are terrestrial, but are not closely related to tortoises. They are in the same family as aquatic sliders, pond turtles, cooters, map turtles, and painted turtles.

photograph by Noppadol Paothong

STATE FISH: Channel Catfish (Ictalurus punctatus), family Ictaluridae, order Siluriformes, found in freshwater habitats in the eastern and southern US, southern Canada, and northern Mexico

They are widely caught, and have been introduced into waterways in other parts of North America and around the world. (In some places they are considered an invasive species).

photograph via: Missouri Dept. of Conservation

photograph by Brian.gratwicke 

[tribbetherium]

'While some of the armored rattiles known as shingles live firmly on dry land, and another class, the seashingles, living entirely in the open ocean, some species dwell in the numerous inland bodies of fresh water all so abundant in the Middle Temperocene, with its ponds, lakes and streams conducive to the flourishing of an assorted diversity of life. The pond turtduck (Anatochelymys atla) is one such species of freshwater shingle, foraging at the bottom of ponds with its broad flattened snout to feed on an assortment of food, ranging from algae and aquatic plants to freshwater snails, clams, worms and other invertebrates that it stores in its cheek pouches and chews when it surfaces to breathe. Found mostly across Gestaltia's tropical regions, the pond turtduck, defended by its sturdy skeleton and protective keratinous armor plates, is largely unconcerned with enemies, feeding at its own leisurely pace--though, if an aggressor proves persistent, the sharp raking claws on its flipper-like limbs acts as an additional deterrent, particularly on land where the turtduck is clumsy and unsuited for a quick getaway.'

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[cadere-art]

What does agriculture and typical plants and animals used in food look like in different regions and cultures?

For the sake of brevity, my answer will only cover this part (but don't worry, I'm working on the plants (and invertebrates) as well) :

VERTEBRATE LIVESTOCK OF UANLIKRI

Thanks to a wide range of environments and intercontinental trade, Uanlikri boasts a wide variety of vertebrate livestock, some domesticated locally, others brought along by settlers from the other continental masses. Most livestock on Uanlikri are ceratopsians (some more highly derived than others).

Caviþ

Pronounced chavith. Caviþ are a highly derived species of ceratopsians originating from the Basin region. The wild species still exist, roaming the southern Basin plains in great hordes.

For the most part, caviþ are kept as beasts of burden and for their meat and leather. In most locales, they are unpopular compared to O'ohu, which are more powerful, meatier, more docile, and have more offspring at once. Nevetheless, keeping caviþ has its avantages: caviþ are smaller, hardy, tolerant of crowding, and produce rough but warm pelts.

In general, caviþ are too small to be ridden by adult antioles, but not for the Apinaat and Abimaat, two peoples of pigmies who make their living on caviþback across the southern Basin plains and on the Matar Peninsula. For the Apinaat and Abimaat, caviþ, wild and domestic, are their whole livelihood. Their use of caviþ as mounts gives them an incomparable edge in warfare and has earned them a fearsome reputation.

Wek

Wek are one of the few non-ceratopsian livestock originating from Uanlikri. They were first domesticated in coastal areas of the Pwetitwì range from large gull-like birds, and spread from there to most northern coastal areas of Uanlikri. Wek are meaty and adaptable birds kept for their eggs, plumage, and guano. They require access to open water to thrive, but accept saltwater and freshwater alike. They are primarily kept in coastal areas, as well as along the Koramme river and Basin Great Lakes, where the slow-moving waters suit them fine.

Kabi

Kabi, a guinea pig sized ceratopsian, are the most widely kept livestock on Uanlikri. The kabi in the picture was enlarged for ease of viewing: the vast majority of kabi breeds are much smaller, though giant breeds do exist. Kabi are a multi-purpose livestock: they are bred for their meat, abundant eggs, soft patterned pelts, and companionship. Kabi are extremely adaptable and very tolerant of crowding. Their ease of keeping in urban environments has made them ubiquitous through all the cities of the continent.

There are hundreds of kabi breeds and landraces on the continent. Kabi have a tendency to establish themselves as feral pests as well as livestock, where natural selection by the environment encourages the development of landraces best adapted to the local climate. They also make excellent pets due to their highly social nature, and many lines of kabi are bred purely for good temperament and pleasing (though sometimes extreme) appearance. Kabi are also ubiquitous overseas: it is unclear where they were first domesticated, but most theories point towards dwarf and standard kabi originating from one domestication event on Uanlikri, and red-leg kabi originating from another domestication event overseas, possibly of a different but related species: this would explain some of the difficulties in breeding dwarf and standard kabi to red-leg kabi.

Tsut

Tsut were one of the livestock species brought along by the Senq Ha Empire, conquerors and settlers of the Western Peninsula. These diminutive therizinosaurids were selected through millenia for an extremely downy, frizzy coat which can be sheared and spun like wool. Of all Senq Ha livestock, tsut were the ones to find the fastest and most widespread adoption, only limited by their destructive browsing habits and preference for hilly terrains and cool weathers. Tsut down revolutionized the world of textiles in Uanlikri, where spun-down fibres were previously very rare and very expensive, requiring capture and shearing of wild animals with very little suitable fibre.

Tsut are primarily raised for their fiber but also provide meat and more importantly crop-milk. Consumption of crop-milk is slow to catch in communities not descended from the Senq Ha, but the Senq Ha's people use crop milk abundantly, using it fresh or processed in dozens of different ways.

Llekme

Llekme were domesticated in the Northern peninsulas of Uanlikri from a species related to the caviþ. They share many of the caviþ issues and advantages, being hardy but temperamental. However, contrarily to the caviþ, they are an extremely popular livestock among both sedentary and nomadic populations Uanlikri's north. There, they are used as beasts of burdens and pulling animals of limited power as well as for their meat. For the desert nomads of the Atashir, llekme provide essential help in carrying their tents and tools; in cities, they are often used as pulling animals, working alone or in teams to pull small carts and coaches.

Hêtâ

Hêtâ are family of highly derived ceratopsians, including a dozen species and subspecies on the mainland and a few endemic island species. They are, in truth, not yet a domestic species. All species of hêtâ are game animals highly appreciated for their ornemental feathers and delicious meat, and there have been several attempts to domesticate various species of mainland hêtâ, none of which have been successful. Mainland hêtâ have extremely nervous dispositions, are prone to dying from stress, and mostly fail to reproduce in captivity: they rarely breed, and when they do, they most often do not provide parental care, leading to the death of the chicks.

This said, there is an ongoing project on the Ojame archipelago to restore and domesticate the near-extinct Ojame hêtâ. The Ojame hêtâ is endemic to the archipelago. Due to the absence of large predators on the archipelago, it has evolved to be larger and much less fearful than mainland hêtâ, but was driven to near extinction by hunting and the introduction of larger, bolder breeds of oujabe [dog analogue] from the mainland and of continental hêtâ imported for use as wild game.

The failure of mainland domestication attempts and a joint desire to preserve and profit from the Ojame hêtâ has led to a unique, unusually coordinated project to domesticate and reestablish the Ojame hêtâ. In a rare show of goodwill and collaboration, this project is shared by both Wetki and Ranaite communities on the archipelago. The Ojame hêtâ is thought to be a promising source of meat and ornemental feathers as its population levels rise and stabilized. Successful captive reproduction has been achieved, and semi-domesticated captive population are being reintroduced to Êrar, the archipelago's largest island where the hêtâ had been completely eradicated.

Wagwacguk

The wagwacguk (wag-wash-guk) is a wild animal living as familial herds in the tundras south of the Kantishian, with a domestic subspecies of marginal range in the lands of the Daghwa-Igdø and the Kantishian High Plateau. It is a large, extremely hardy animal with a warm, plush coat and thick leather. For the Daghwa-Igdø, wagwacguk are their main livelihood. One month per year, they feast on the fresh meat of wagwacguk calves, culling their herds as the first dayfrosts touch their lands; the later kills are preserved by smoking and freezing. The rest of the year, wagwacguk blood provides them with most of the protein in their diet. Wagwacguk pelts, leather, guts, horn and hooves are the materials involved in most of their material culture.

Though domestic wagwacguk are most closely associated with the Daghwa-Igdø, they are also kept by the Oubixwø-øi of the Kantishian high plateau as part of the Oubixwø-oi's diverse survival strategies.

O'ohu

O'ohu are domestic hadrosaurs named, in most regions where they are kept, after their loud and haunting cry. They are the largest and second-most widespread livestock on Uanlikri. Where they are kept, they are invaluable for their work as beasts of burden: plowing fields, pulling carts, carrying charges of all kinds. They are essential to the work of peasants and armies alike, and they are surprisingly fast. Historically, they have often been used in active combat, pulling war chariots. They cannot be ridden: their back ridge is too fragile to bear the weight of a rider and their alternatively bipedal and quadrupedal gait makes balancing a saddle impossible. They are also used for meat, blood, leather, and other byproducts. Their finely scaled and patterned leather is considered especially attractive, and their hollow horns are often made into music instruments. In many cultures, O'ohu grastroliths are considered to have medicinal properties as the ultimate digestive aid, and are often sold at a considerable markup by gastrolith merchants.