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Today we feature one of Australia’s best-known and best-dressed snakes, the red-bellied black snake (Pseudechis porphyriacus).  This exceedingly handsome reptile lives all along the eastern coast of the island continent and grows to lengths of 1.5 to 2 meters (5.5 to 6.5 feet).   It is a generalist predator which eats small mammals, reptiles (including fellow red-bellied black snakes) arthropods, and above all, frogs.  This fetching snake is a member of the elapidae family—a group of toxic snakes which includes such famous genera as coral snakes, cobras, and kraits.

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The red-bellied snake is indeed venomous: its venom is a complex mixture of neurotoxins, myotoxins, and coagulants.  However, when the snakes bites people (which they are loath to do) they rarely inject a lethal dose of venom.  When threatened they try to hide in the urban woodlands, billabongs, or scrublands where they live.  If backed into a corner they will make a threat display by extending their cobra-like hood and hissing.  Australians, who live with many horrifying venomous snakes, seem to regard red-bellied black snakes as comparatively benign although I certainly wouldn’t want one to bite me!).

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Snakes of this species are ovoviviparous—they hold their eggs inside their body until the young hatch.  This is no mean feat, since mother snakes can give birth to litters of up to 40 little baby snakes!

Red-bellied black snake, Lota.

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Back during the glorious infancy of my blog I wrote a great deal about the demi-god Heracles (a.k.a. Hercules)–the greatest classical hero, who slew so many of the children of Echidna (and even grappled with Echidna herself).  For some reason, when I was growing up, I always had a mental picture of Heracles as a meat-head who solved every problem by means of brute strength; however, as an adult my perspective on the hero has changed greatly.  The craftiness with which Heracles faced problems like the Hydra and the journey to the underworld reveals that his cunning and his political guile became greater and greater as he ground on through his quests and labors towards godhood.  A big part of absolute power involves mastering craftiness…and manners. In fact the story of Heracles is really an epic quest to please a picky mother-in-law (but more about this later). At any rate, when his plans went awry, Heracles always had brute strength, but it often rebounded on him and was the source of his greatest problems as well as his greatest victories.

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Which brings us all the way back around to Hercules’ first great exploit—which was purely of the brute strength variety.  Heracles was the son of Zeus and the beautiful shrewd mortal woman Alcmene (who had a magical pet weasel—but more about that another day).  Naturally Hera hated this rival and she chafed at the glorious prophecies of what the child of Alcmene would one day accomplish.  Hera tried to prevent the birth of Heracles by means of her subaltern, the goddess of childbirth.  When this failed, she resorted to brute force on her own right and she sent two mighty serpents to kill the baby in his crib.  Heracles grabbed one of the poisonous serpents in his right hand and the other in his left and throttled them to death with super strength. The first glimpse we get of Heracles is a majestic picture: an infant throttling two great snakes in his bare hands.  This image was sculpted and painted again and again throughout the history of western art.  It foreshadows Heracles’ difficult life, and his triumph, and his methodology.  Here is a little gallery of baby Heracles/Hercules throttling snakes:

baby Hercules

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Black Mamba (Dendroaspis polylepis)

Black Mamba (Dendroaspis polylepis)

I have been putting it off forever, but Halloween is rolling in and we need the A-list material… let’s talk about the black mamba (Dendroaspis polylepis).  Not only do black mambas have the scariest & sexiest name in herpetology (and maybe beyond), they fully live up to their fearsome reputation.  Black mambas are among the fastest snakes in the world—indeed they may be the fastest (it is apparently difficult to make deadly poison serpents run on a treadmill).  Their venom is a horrifying cocktail of neurotoxins including an exceedingly effective dendrotoxin which attacks the ion channels which allow nerve cells to communicate with muscles.

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Black mambas are diurnal ambush hunters.  They inhabit a giant swath of sub-Saharal Africa from the northern Sahel down to Namibia and Mozambique in the south (although they are absent from certain deserts and rainforests within this vast territory). The snakes live on small intelligent mammals like hyraxes and bushbabies…but surely they must eat other creatures as well.  In turn mambas are preyed on by the fearless yellow mongooses, snake eagles, and cape file snakes–which are seemingly immune to the poison.  Africa has some really intense inhabitants.  It goes without saying that people kill them too, out of dread.

Speaking of which, according to lore, black mambas are highly aggressive and attack with no provocation, but this does not seem to be borne out by evidence.  Knowledgeable herpetologists assert that black mambas are wisely afraid of humans (we are, after all, the most terrifying invasive aggressive species from Africa) and they try to flee us when possible.  Still if you happen upon one of these snakes it might be wise to avoid it rather than trying to impress it into submission with a list of our atrocities. They can strike with extreme speed and sometimes bite multiple times (which is bad news considering that a person bitten even once can keel over in less than 45 minutes and nearly all untreated bites are fatal).

This albino black mamba is not clarifying anything, but is strangely endearing

This albino black mamba is not clarifying anything, but is strangely endearing

In gentler moments mambas mate once a year in early spring.  Females lay clutches of 6-17 eggs which hatch in about ninety days. Baby black mambas emerge from their eggs with fully functioning venom glands, so don’t pick up the baby snakes no matter how cute they are (?).

[contemplates photo, passes out]

[contemplates photo, passes out]

Black mambas are not black! They are diurnal hunters and are thus the nondescript color of dust or contemporary office furniture–the better to blend in to scrublands, forests, and grasslands which they inhabit.  Their name comes from the insides of their mouths which are indeed as black as Goya’s nightmares. I knew a girl in junior high school who said “Oh mamba!” when she was impressed, which I thought was really endearing.  The word is apparently Nguni in origin (although the snake is more broadly known than the tongue it is named in).  Mambas are elipsids–close relatives of cobras.  The other species of mamba are arborial, but black mambas stay closer to the ground.  Black mambas seem to have faintly mocking smiles–so at least they are enjoying themselves [citation needed].

ssssmile!  You only live oncce.

ssssmile! You only live oncce.

Echis ocellatus (photo by Anders Johansson)

Echis ocellatus (photo by Anders Johansson)

A few weeks ago I wrote about Fav-Afrique, the superb anti-venin which is going off the market because market incentives do not properly address real human concerns.  The anti-venin is a cocktail which is meant to counter the venom of numerous different snakes from central and West Africa. In that post, I promised to write about some of these venomous reptiles, which I have so far failed to do.  When I was looking at the list, one name stood out because it was the most dangerous snake in Africa (in terms of the number of people killed by its venom), yet I did not recognize the name at all-the West African carpet viper (Echis ocellatus).  This husky viper, which is camouflaged with a chaotic ladder of dark bars and pale stipples, is apparently Africa’s most dangerous snake—one of the deadliest animals in the word in terms of human mortality and suffering—but I have never heard of it.  Have you?

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The West African carpet viper doesn’t even have a good page (in English) on Wikipedia.  It is hard to find out about the creature without turning to 19th century explorers or freaks who raise it for a hobby.  Most of the web articles I found about it were scary medical papers about failed attempts to come up with effective anti-venins for the viper’s venom.  Here is what we do know about this tubby killer. Echis ocellatus can be found from Mauritania in the north down along the Bight of Benin to Cameroon.  It ranges east into the Sahel as far as Chad, Niger, and the Central African Republic.  The snake is adept at surviving in dry scrubland on lizards and rodents. Females can lay immense clutches of up to sixty eggs!

Echis ocellatus (at least acfcording to the internet)

Echis ocellatus (at least acfcording to the internet)

That is all I could reliably find out, but we know that the animal is a viper—which provides us with a great deal of information.  Vipers are fearsome lurking predators capable of seeing infrared wavelength radiation (which means they can track prey in the dark based on body heat).  Some pit-vipers like American rattlesnakes are famous for warning intruders off—and apparently the carpet viper can rasp its saw-toothed scales together to make a warning sound, but this subtle warning often goes unheeded by firewood gatherers of the scrubland.  Based entirely on body count, Echis ocellatus must be an angry & short-tempered character (I have mercifully never met one—so my words are speculation).

There is more information about the venom of Echis ocellatus than there is data about the snake, but the information is frustratingly technical.  Suffice to say, the snake produces a formidable cytotoxin, a protein which is damaging to cells.  Bites from the viper are marked by terrible tissue necrosis and hemorrhage at the site of envenomation.  I’m really sorry—the main things I have found out from looking into this interesting but enigmatic animal is that: (1) The internet is still an imperfect information source about some really important things; (2) I need to read French to write about West Africa, and (3) do not mess with Echis ocellatus! Leave them be and tread with great caution in dust colored places of the Sahel!

Uh...

Uh…

The Black Mamba (Dendroaspis polylepis) Africa's most infamous venomous snake

Sanofi Pasteur is a French biomedical corporation—the vaccination division of Sanofi-Aventis Group, the world’s third largest drug company. The company produces “Fav-Afrique” a highly effective snake antivenin cocktail used to treat bites from Sub-Saharan Africa’s ten most poisonous snakes…or I guess I should say they used to make Fav-Afrique.  Snake antivenin is difficult and expensive to produce: making Fav-Afrique involves keeping and milking extremely poisonous snakes and then giving this venom to large domestic mammals such as sheep and horses.  A course pf Fav-Afrique costs around $500.00—which is big money in Sub-Saharan Africa—and the production was already heavily subsidized by NGOs and governments.  Yet somehow the entire affair was not economically feasible for Sanofi Pasteur.   There are a limited number of fairly shelf-stable doses left, but the earliest anyone is going to make a comparable product is 2018.

This job looks hard

This job looks hard

Snakebites are not particularly deadly here in the United States where snakes kill maybe 2 people a year, however the reptiles of Southern Africa are more formidable…while medical and emergency infrastructure there is a lot poorer (and there are far more people who live closer to the ground) so an estimated 10,000 to 20,000 people a year die of snakebite in Sub-Saharan Africa.  That is a huge number—for comparison the 2014 Ebola outbreak which (rightly) scared the bejeezus out of everyone “only” killed 6,500 people.

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All of this makes me wonder anew about the way incentives work in the broader affairs of the world. I understand why medical companies don’t want to mess with a process which is dangerous and complicated yet provides little (or no) profit.  Would you want to do that? Pro-market adherents (who increasingly strike me as bastards) would probably argue that the price of a course of antivenin should be much much higher (which is the case here in America with our sky-high health care costs)…but who would then pay for it in Africa?  Should we not have antivenins—even though we know how to make very fine ones which could save many lives?

By the way, Médecins Sans Frontières is a good organization

By the way, Médecins Sans Frontières is a good organization

It seems likely that powerful NGOs like the Gates Foundation and Médecins Sans Frontières will step in and take over Fav-Afrique–once they build an organization to master the complicated process of producing it.  Perhaps the entire flurry of media attention (like this article) is a useless kerfluffle designed to get frightened people to read articles…but I don’t feel like it is.  I feel like this whole error begs larger questions of how our system works and doesn’t work.   I don’t have any answers to macro-scale resource allocation questions, but I can see the invisible hand of the market trembling and doing dastardly and stupid things and it bothers me.

Tanzanian Puff Adder (Bitis arietans)

Tanzanian Puff Adder (Bitis arietans)

Of course all of this also begs question about what these ten super-poisonous African snakes are and where and how they live. I can answer questions about these amazing and formidable mambas, vipers, cobras, and puff adders!  I will be writing more about them in weeks to come…so even this poisonous cloud has a scaly silver lining.

King Cobra (Ophiophagus hannah)

King Cobra (Ophiophagus hannah)

Exciting celebrity news for Central Florida today! A king cobra (Ophiophagus hannah) has decided to forgo its native range—the forests in India and Southeast Asia–and pay a visit to Orlando, Florida.  The king cobra is the world’s longest venomous celebrity with a length of up to 5.6 meter (18.5 feet) (although the one “visiting” Florida is a mere 2.2 meters (8 feet) long).  Unlike many other celebrities, king cobras are known for intelligence, sensitivity, and potent neurotoxic venom.  They (king cobras) also have the ability to rear up the anterior 1/3 of their body, extend their hood and growl loudly. The creature escaped decided to visit Orlando when a tree limb dislodged by a storm crashed open its terrarium.

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King cobras are known for hunting smaller snakes and large rodents.  A ten man team is desperately trying to capture the celebrity before it bites anyone or escapes into the wider ecosystem (like Florida’s famous albeit disreputable pythons).

Hold on…my editor is frantically mouthing that King Cobras are not part of America’s celebrity culture—apparently they are only revered in Hindu and Hinayana Buddhist societies and Christians deplore them (and all other snakes) as taboo. King cobras have never been featured on “American Idol” or “Dancing with the Stars” (although I think it would really spice up those extremely formulaic shows).

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It is important to distinguish between celebrities and dangerous poisonous snakes, I have failed to do that here and I am exceedingly sorry. Please be sure to make this distinction in your own life (except when feeding rats to Sean Penn).

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Gafftopsail Catfish (Bagre marinus)

Gafftopsail Catfish (Bagre marinus)

This amazing looking fish is a gafftopsail catfish (Bagre marinus). It is an Atlantic Ocean catfish which lives in coastal waters off of North America from the Caribbean up through the Gulf of Mexico north to the mouth of the Hudson. As you might guess from its intimidating Fu Manchu mustache and barbed flavor savor, the gafftopsail catfish is a formidable predator which eats crustaceans and smaller fish. The fish has a sinister forked tail, a wavelike hump, and a jaunty dorsal spine looks like a sail (and gives the fish its common name). Additionally like most saltwater catfish, the gafftopsail catfish has several venomous, serrated spines.

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The largest gafftopsail catfish ever caught weighed an impressive 4.5 kg (10 pounds), but generally the fish are much smaller. They usually measure about 43 cm (17 inches) in length. Male gafftopsail catfish are solicitous fathers. When the female lays her eggs, the male fertilizes them and collects them in his mouth. He carefully protects the eggs until they have hatched, and thereafter his young take shelter from predators inside his mouth until they are old enough to set out on their own.

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Woodblock prints of ages past show giant octopuses ripping apart boats and feasting on sailors like popcorn.  These artifacts of ancient sea-lore make for rousing images, but they are quite wrong:  octopuses are fierce and cunning hunters but they present little danger to humans—with a noteworthy exception.  The truly dangerous octopuses are not giant monsters (perhaps the artists of yesteryear were thinking of the mighty giant squid?) but rather tiny jewel-like beauties from the genus Hapalochlaena which includes only three or four species.  Known as blue-ring octopuses the tiny creatures swim in tide pools and shallows of the Indo-Pacific Ocean from Japan down to Australia (where they are most prevalent).  Blue-ringed octopuses live on shrimp, crabs, minnows, and horseshoe crabs.  They are tremendous hunters who use camouflage, stealth, and guile to catch their prey.  However, these tools pale before their greatest weapon: the little octopuses are among the most poisonous creatures on planet Earth.

(photo by Aluki from Flickr)

Like the flamboyant cuttlefish, the blue-ringed octopus does not like to bite without giving warning but advertises its toxicity with vivid coloration.  The octopus can conceal itself with tremendous prowess however, as soon as it becomes aware of a predator or some other threat, it dials up its coloration changing from muted reef tones to brilliant yellow with iridescent blue rings.  If you see something like this in the ocean, for heaven’s sake don’t touch it.  The octopus’s warning colors let ocean predators know to leave it alone but immediately attract humankind’s magpie urge to grab shiny things.  Although blue-ringed octopuses are good natured and have been known not to bite people who were provoking them rather intensely, their bites have caused more than seventy recorded fatalities in Australia. The octopus has a tiny beak and often a victim does not realize they have been bitten until they began to fall into paralysis and their respiration starts to fail.

Argh, I said don't touch it

The venom of the blue ringed octopus is a complicated pharmacological cocktail which includes tetrodotoxin, 5-hydroxytryptamine, hyaluronidase, tyramine, histamine, tryptamine, octopamine, taurine, acetylcholine, and dopamine. The most active ingredient tetrodotoxin blocks the sodium channels which conducting sodium ions (Na+) through a cell’s plasma membrane.  This causes total paralysis for the octopus victim, however if clever and persistent rescuers are present at the time of the bite they can rescue the unfortunate soul with continuous artificial respiration.  This is no small matter as bite victims are often rendered completely unresponsive by the paralytic victim.  Although completely conscious they are unable to communicate in any way or even breathe.  If artificial respiration is initiated immediately and continued until the body can metabolize and eliminate the toxin, bite victims can survive (although it sounds like rather an ordeal).

Blue ringed octopuses are tender and solicitous mothers.  The mother octopus lays a clutch of approximately 50 eggs in autumn which she incubates beneath her arms for about six months (during which time she is unable to eat).  When the eggs hatch, the mother octopus dies. The baby octopuses reach sexual maturity in about a year.  Despite their cleverness and beauty, the animals are as ephemeral as they are deadly.

Under its mother's watchful eye a baby southern blue-ringed octopus (Hapalochlaena maculosa) emerges from its egg.

Poison is very common in the animal kingdom (and throughout the other kingdoms of life) both as a means of defense and as a weapon for hunting, however only a tiny handful of mammals are poisonous.  A few shrews have mildly venomous bites.  The European mole has a toxin in its saliva which can send earthworms into a coma (allowing it to store them in the larder for later).  The Solenodon, a strange burrowing nocturnal insectivore is perhaps most toxic among the mammals–with one glaring exception. At the beginning of the month we wrote about the clever echidna–a monotreme with unusual brain physiology.  The echidna’s closest relative, and the world’s only other remaining monotreme, the duck-billed platypus is the planet’s most poisonous mammal by far.  Not only do platypuses have bills, lay eggs, and utilize electrical sensory apparatus to hunt, but the male has a moveable poisonous spur on his hind legs which is attached to a venom-producing crural gland.  Only the male platypus is capable of producing a toxic peptide cocktail and injecting it through his spurs. Female platypuses (and all echidnas) have rudimentary spurs which drop off and lack functioning crural glands. Platypus venom causes pain and hyperalgesia—which means an increased sensitivity to pain–so you shouldn’t cuddle male platypuses no matter how adorable their funny little bills may look to you.

The crural glands...and the spur!

The Stanford neuroblog (from whom I borrowed the attached image of a platypuses’ poisonous organs and appendages), notes the similarity of platypus venoms with reptile venoms, “One evolutionary curiosity: the defensin-like peptides found within the platypus venom are also found within reptile venom. However, genetic analysis in 2008 revealed that the platypus peptides evolved independently from the reptile peptides, although both were derived from the same gene family.”  Its curious to think of how our ties with reptile forbears are manifested in the curious and endearing (and poisonous!) platypus.

Eek! Get down...he's got a platypus!

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