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bethanythebogwitch · 2 days

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Wet Beast Wednesday: spiny softshell turtle

It may be neither Flat Fuck Friday nor Turtle Tuesday, but because this is my series and I can do what I want, I'm talking about a very flat turtle. The spiny softshell turtle (Apalone spinifera) is the most widely distributed and possibly the most common softshell turtle in North America. Its range covers most of the Eastern half of the USA and stretched into Canada and Mexico. There are 6 subspecies separated by geography and hybridization can happen in places where their ranges cross. Hybridization has also been known to happen with the Florida softshell (Apalone ferox). The subspecies are the northern (A. s. spinifera), gulf coast (A. s. aspera), Texas (A. s. emoryi), pallid (A. s. pallida), Guadalupe (A. s. guadalupensis), and black (A. s. atra) spiny softshells.

(Image: a spiny softshell turtle seen from above and to the side. It is a turtle with a wide, flat shell. Its head and one foot are visible. The head is skinny and has an elongated nose. The foot is wide and flat, with webbed toes. The turtle is an olive green with black dots on the skin, yellow stripes on the face, and dark spots on the shell. End ID)

The thing that makes a softshell a softshell is the lack of keratinized scutes on their shells. This makes the shells smooth and leathery. The center of the shell has a layer of solid bone user it, but this does not extend to the edges of the shell, making it less rigid. Softshells are the fragile speedsters of the turtle world. Their shells are a lot lighter and often more streamlined, allowing for faster movement both on land and in water, but they provide less defense. Spiny softshells have spiny projections along the front edge of the carapace (upper shell), with males having more than females. They are some of the largest North American freshwater turtles. Females can reach a carapace length of 54 cm (21 in) and 11 kg (25 lbs) while the smaller males max out at about 25 cm (10 in).

(Image: a spiny softshell being held by a person, seen from the front. The leading edge of the carapace is visible, showing off the small spines. End ID)

Spiny softshells have wide, flat, paddle-like feet with three claws and an elongated nose that acts like a snorkel. The turtles are born a bright olive color with striped faces and dark spots on the shell. Males keep their juvenile coloration for their entire lives while females grow darker ad lose many of their markings. It can be very difficult to tell females of different subspecies apart, while males and juveniles can be distinguished by their markings. Smooth skin and highly vascularized membranes in the cloaca, mouth, and throat allow the turtles to breathe by diffusing dissolved oxygen from the water into their blood.

(Image: a male and female spiny softshell facing each other. The male is less than half the size of the female and has an olive colored shell and skin, with dark spots on the shell. The female is a uniform muddy brown color. End ID)

Spiny softshells are generalists able to live in a wide range of habitats. They prefer streams, rivers, and ponds with muddy or sandy bottoms and high visibility, but can live in most freshwater habitats. Softshells are diurnal, spending their days basking and feeding. Being turtles, they are ectothermic, meaning their body temperature matches the surrounding temperature. To warm themselves up, the turtles bask in the sunlight. They can often be found resting on exposed rocks, logs, sandbars, or shorelines. While not particularly social animals, the turtles will bask in groups. When threatened, softshells will attempt to swim away and/or bury themselves. In the right sediment, a softshell can bury itself in under a second. Because their shells are less rigid, softshells have to actively defend themselves when cornered and will bite and scratch. People have to be careful when handling them. They brumate (that's hibernation for reptiles) during winter. While brumating, they bury themselves underwater and slow their metabolism and oxygen requirements. In this state they can fully sustain themselves on oxygen absorbed through their skin or special membranes.

(Image: a spiny softshell turtle buried in its hunting strategy. Only the head is visible above the sand. End ID)

They are primarily carnivores and will eat anything that can fit in their mouths. Aquatic insects, crayfish, worms, amphibians, mussels, snails, fish, and more are on their plate. While capable of fast swimming, they are not pursuit predators. They employ two primary hunting strategies. The first is to bury themselves in the sediment and wait for prey to come by. The second is digging in the sediment to find worms and other animals. Fish have been known to follow digging turtles around to feed on animals unearthed by them.

(Image: a spiny softshell in captivity. It is swimming at the surface of the water in a tank, amongst artificial leaves. End ID)

Spiny softshells mate in spring. Males attempt to woo females by swimming over to them and bumping heads together. The male then sits on top of the female to mate. Unlike most species of turtles, the males do not grab onto the female's shells during mating. Eggs are laid between summer and early fall and will hatch next spring. The female will dig a nest in sandy or gravelly banks and bury the eggs once they have been laid. She provides no further care. Females will typically mate multiple times each year, with each mating having a different nest. The juveniles take 8 to 10 years to reach sexual maturity and they can live up to 50 years in the wild. Many turtles determine sex by the temperature the eggs are incubated in. This is not the case with spiny softshells, who have genetics based sex determination.

(Image: a group of 5 juveniles. The photo focuses on two who are sitting next to each other. One has its front right leg on the shell of the other. They have similar coloration to an adult male. End ID)

(Image: a newborn emerging from its egg. The egg is round and white, looking like a ping-pong ball. Only the head of the turtle has emerged. End ID)

Most subspecies of spiny softshell are classified as least concern or near threatened by the IUCN, meaning they are not in danger of extinction. The exception is the black spiny softshell, also known as the Cuatro Ciénegas softshell, which is critically endangered. The primary threats to the turtles is habitat loss due to human activity. Adults have no natural predators outside of the Florida and adjacent state populations, which are prey to alligators. Juveniles are eaten by a variety of animals including fish, snakes, raccoons, and herons. People will also eat the adults. Because it can take a whole decade for juveniles to become reproductive, losses in population take a long time to replace. They have been introduced to areas outside of their native range, most notably the western USA. Most of these introductions are due to people releasing pet turtles into the wild.

(Image: someone holding a juvenile. The shell is 2-3 times the size of the human's thumb. End ID)

#i typoed it as softhsell more times than I care to admit #wet beast wednesday #turtle #turtles #softshell turtle #soft shell turtle #spiny softshell turtle #reptile #biology #zoology #ecology #animal facts #freshwater ecology #aquatic biology #informative #educational #image described #turtle power #herpetology

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bethanythebogwitch · 23 days

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Wet Beast Wednesday: moray eels

This week on Wet Beast Wednesday I'll be going over something amazing, a fish with a sense of morality. You see, the moral eel is known for, what... I think I'm reading this wrong. Oh, MoRAY eel, not moral. Well this is awkward. Hang tight, I need to go redo my research.

(Image: a green moray (Gymnothorax funebris) swimming outside of its burry, with its whole body visible from the side. It is a long, slender fish that looks a bit like a snake. A long fin starts just below the head and continues down the length of the body. The body is arranged in a wave pattern. It has a pointed snout and small eyes. Its body is a yellow-green color. In the background is the sandy seafloor, dotted with various sponges and corals. End ID)

Moray eels are true eels, meaning they are in the order Anguiliformes. Yeah, I did wolf eels, electric eels, and lamprey eels before I got around to actual eels. There are over 200 known species of moray eel in 15 genera. Like other eels, they are elongated bony fish with extra vertebrae and reduced fins. Moray eels have fewer fins than most eel species, only having a dorsal, anal and tail fin that merge together and run down the back of most of the body and underneath portion of it. They achieve motion by undulating this long fin and sometimes undulating the rest of the body as well. Moray eels aren't the fastest of fish, but they can swim backwards, something almost no fish can. The head has a long snout with wide jaws. Most species have long fangs used to grab onto prey, but a few species are adapted to eat hard-shelled prey and have molar-like teeth to crush through shells instead. Probably the coolest feature of morays are the pharyngeal jaws. This is a second set of jaws located in the back of the mouth. When the eel bites onto prey, the jaws can be shot forward to grab the food and help pull it into the throat. While lots of fish have pharyngeal jaws, morays are the only ones who can extend their pharyngeal jaws forward and use them to grab prey. Morays have smooth, scaleless skin that is often patterned to provide camouflage. The skin is coated in mucus that provides protection from damage and infection. In some species, the mucus can be used to glue sand together to help reinforce burrows. Morays lack lateral lines, a system of organs found in most fish that senses changes in water movement. Their sense of smell is their primary sense. The size of morays varies between species. The smallest species is the dwarf moray eel (Gymnothorax melatremus) which reaches 26 cm (10 in) long. The largest species by mass is the giant moray eel (Gymnothorax javanicus) which can reach 3 meters (10 ft) and 30 kg (66 lbs) while the longest species is the slender giant moray (Strophidon sathete), the longest known specimen of which measured in at 3.94 m (12.9 ft).

New reaction image

(Image: a giant moray (Gymnothorax javanicus) emerging from a burrow. It is brown and mottled with yellowish patches. Its head is pointed at the camera and it's mouth is wide open, aming it look shocked. End ID)

(Image: an anatomical diagram of the skeleton of a moray eel emphasizing the pharyngeal jaws and the muscle attachments. End ID. Art by Zina Deretsky)

Moray eels are found throughout the Atlantic, Pacific, and Indian oceans. Different species are found in different temperatures and depths, though most species live in relatively shallow, warm water. Several species can live in brackish water and a few will swim upriver and live for a time in fresh water, though there do not appear to be any species that live their entire lives in fresh water. Morays are ambush predators who rely on the element of surprise. They live in small, tight places such as holes in coral, gaps between rocks, or sandy burrows. When prey passes, the eel can lunge out and grab it. Unlike most fish, the eel cannot use suction feeding due to the shapes of their mouths. They have to rely on lunging froward and catching prey with their mouths. Their mouths are adapted in shape to push water to the sides. This reduces water resistance and avoids creating a wave that could push prey away from the eel. If an eel catches prey that cannot be swallowed whole, it will tie itself in a knot while biting on to the food. By pulling its head through the loop, the eel can rip the food into bite-sized pieces. Spending most of their times in burrows also provides protection from predators, especially in juveniles or smaller species. At night, the eels will come out of their burrows to hunt sleeping prey while the larger predators are asleep. Giant morays have also been seen engaging in interspecies cooperative hunting with roving coral groupers (Plectropomus pessuliferus). The eels can fit into small crevices the groupers can't to flush prey into the grouper's path while catching their own. Morays are mostly solitary species and many can be territorial. They are known to be shy and will retreat into their burrows if they feel threatened. They are also curious and many species are quite intelligent.

(Image: a male ribbon eel (Rhinomuraena quaesita) on a coral reef. It is a very long and slender eel with its body curved in many waves. It is brightly colored, with a blue-purple body, yellow fin and face, and a long black and white stripe running down the back half of the body. On the nostrils are two feather-like structures. End ID)

Morays reproductive strategies are poorly known and differ based on species. While many species seem to have no set mating season and will reproduce whenever they can, others will mate at the same time every year. Some species seem to have dedicated spots to lay their eggs and a few are believed to be anadromous, meaning they travel from the sea to fresh water to spawn. Meanwhile, some of the species that spend a lot of time in fresh water are catadromous, meaning they return to sea to mate. Females will lay their eggs and the male fertilize them. After this, they depart, providing no parental care. As with all true eels, moray eels begin life as leptocephalus larvae. This type of fish larvae is notable for its resemblance to a simple, transparent leaf with a head on one end. These larvae are unique and poorly understood, despite being the larval stage of a lot of different species of fish. They are unusually well developed for larvae, capable of active swimming and generally living life. In fact, some particularly large leptocephalus larvae were initially mistaken for adult fish. They feed mostly on bits of drifting organic material called marine snow and can remain in the larval stage for up to 3 years, with those in colder conditions usually taking longer to metamorphose. All leptocephalus larvae start out with no sex organs, then develop female organs, then develop male ones, becoming simultaneous hermaphrodites. They will ultimately become eith male or female and it is likely that environmental factors are the main determining factor. During metamorphosis into a juvenile, the leptocephalus can reduce in size by up to 90%, resulting in the juvenile being smaller than the larva. The process of maturation is poorly understood, but it seems that most morays will be sexually mature by three years of age.

(Image: multiple photos of a particularly large leptocephalus larva (not sure what species). It is a translucent organis, wth a body shaped like a very long leaf, narrow at both ends. In the frint is a very tiny head. End ID)

Morays are shy and generally avoid humans. Though some cultures have hunted them for food, they are often not considered a particularly good food source. Many species have high levels of chemicals called ciguatoxins in their bodies, which can lead to a condition called ciguatera fish poisoning if eaten. The largest threat to morays is habitat loss. This is especially true for the many species that live in coral reefs, which are in increasing danger due to global warming. Attacks on humans are rare and usually happen as a response to a human sticking their hand in the eel's burrow. Some of the large species could cause significant damage with a bite. Some species, usually the smaller ones, are found in the aquarium trade, thought they are not good pets for beginners as even the smallest morays are still large for aquarium fish and have some specific requirements. The curiosity many morays have has led to some becoming familiar with and even friendly to humans, often the result of feeding them. They can recognize individual humans and remember them over the course of years. Aquarium employees sometimes report that the eels will come to nuzzle and play with them and have personalities like dogs. Marine biologists and professional SCUBA divers Ron and Valorie Taylor befriended a pair of eels they named Harry and Fang at the Great Barrier Reef who would remember them and come out to visit them year after year.