Starting into the herpetology season part II: Orgiastic toad balls

Mass gatherings of mating common toads (Bufo bufo) are probably among the most spectacular herpetological phenomens you can see among European amphibians. It is really an incredibly sight to see dozens or even hundreds of this usually quite solitary anurans gathered together. It is not only interesting to see such a large number of individuals with all their range of intraspecific variation, but also to see a lot of fascinating, weird and sometimes even quite obscene behavior.

DSC04357

At the end of March I visited a pond which is every spring visited by mating toads. I found only a few specimens in the water, some toads were even still walking or sitting around on land set back from the pond and apparantly on their last steps of their journey to the mating ground.

DSC04362

One male toad jumped on the shoe of a young boy who visited the pond with his grandparents. I don´t think he knew what the toad was going to do when it clinged to his foot.

DSC04363

It tried to perform the amplexus, a mating behavior in which the males grab the females with their arms and cling on their backs.

DSC04364

Some of those male toads have a quite extreme sexual urge, and are quick to try to mate with just anything, including other amphibians or even inanimate objects.

When I came only a few days later again on the pond, the weather was now already much warmer, it was just full of toads, sitting and swimming around, and of course – mating.

Here is a photo of a large female which was sitting in the gras, surprisingly still without a male.

DSC04383

Other females had already found a fitting male, like this happy couple shows:

DSC04427

This photo shows also quite well the strong sexual dimorphism:

DSC04487

It also looks really strange when the females and males are walking together in this posture.

DSC04514

Other pairs were already together in the water.

DSC04404

Other females had lesser luck and were literally sieged by horny toad males.

DSC04458

The females in those balls were no more visible, and it can happen on occasion that they drown under such masses of wannabe-lovers.

DSC04455

There is even a case reported in which an adult male common moorhen (Gallinula chloropus) nearly drowned because several male toads clinged on its head and neck.

DSC04452

Another photo showing the large numbers of male toads in some areas of the pond.

DSC04490

This obviously quite frustrated male continuously tried to copulate with a clump of moor frog (Rana arvalis) spawn.

DSC04477

I could also observe a toad male which tried to jump on a moor frog, but apparantly quickly realized his error. You can also see a lot of egg strings around the toad and the two moor frogs.

DSC04414

Another opportunistic toad male jumped out of the water up to me and chased me for several metres. That´s really a very weird feeling if a tiny toads is chasing you. Somewhat later another toad also suddenly chased me, or perhaps more probably, my shoes, which must have appeared to him like a potential female toad.

DSC04483

Here is a photo of the pond, which is located in a small park surrounded by woods.

DSC04499

Meanwhile I have already seen the first tadpoles, and within a short time, the whole pond will be full of them.

Veröffentlicht unter Amphibien, Naturbeobachtungen | 3 Kommentare

Starting into the herpetology season part I: Newts are coming

After the last entry spontaneously disappeared due to a server problem (together with the draft of the next part of the series), I make a somewhat shortened second version to restore the first part again.

So here are some photos I took two days ago during a walk, when I encountered a common newt (Lissotriton vulgaris) sitting on an asphalt field road. It was probably on its way to a pond or ditch. It was one of the first amphibian species I´ve seen this year, after I discovered the first alpine newts, common toads and moor frogs only a few days before.

Common newt Lissotriton vulgaris (2)

Common newts are besides alpine newts (Ichthyosaura alpestris, a pretty awesome name BTW) by far the most common caudates here around.

Common newt Lissotriton vulgaris (3)

In their terrestrial form common newts are sometimes mistaken for lizards by people, because their dry and finely granulated skin doesn´t appear very amphibian. Furthermore their tails have not the large skin appendiges which form the fins and crests which develop in the aquatic form during the mating season.

Common newt Lissotriton vulgaris (1)

Another photo showing the specimen in dorsal view:

Common newt Lissotriton vulgaris (4)

After I took the photos I carefully placed it in the nearby gras, as this road is comparably strongly frequented by cyclists, joggers and also cars, what sadly sometimes results in a lot of roadkilled amphibians at early morning, especially of fire salamanders.

Veröffentlicht unter Amphibien, Naturbeobachtungen | Hinterlasse einen Kommentar

Under the hermit crab´s shell

Hermit crabs are freaky and cool for many reasons. They live inside the external skeletons of dead snails to cover their misshapen abdomens, which they even sometimes plant with living anemones, they have some of the most extensive body assymetries of all crustaceans, some of them are among the most succesful terrestrial decapops of the world while their largest member, the coconut crab Birgus latro is by far the largest terrestrial arthropod since the Carboniferus.

When I was two years ago at Crete I had the chance to take a closer look at two dead hermit crabs from some fishermen´s bycatch.

DSC06163

You can usually only see the front part of the body, but in this dead individuals I could easily separate the hermit crabs from their shells to take a look at their abdomens.

DSC06164

They had been lying there already since some time in the sun, so the very soft abdomens were already somewhat shrunken.

DSC06165

A look at the other specimen:

DSC06162

On the left side of the abdomen you can also see the highly modified pleopods used to hold the abdomen inside the shells.

DSC06160

Close-up of the abdomen:

DSC06160 2

For comparison a photo of a quite fresh Pagurus bernhardus from Wikipedia, with the abdomen still in full shape:

Pagurus_bernhardus

Pagurus bernhardus. Source: Wikipedia

Here´s also for the better understanding of the anatomy a schematic depiction of a Hermit crab without shell:

FMIB_46415_Common_Hermit_Crab_(Eupagurus_bernhardus)_removed_from_the_shell

Common Hermit Crab (Eupagurus bernhardus). Source: Wikimedia Commons)

 

Veröffentlicht unter Anatomie, Arthropoden | Hinterlasse einen Kommentar

At the birdfeeder: Grosbeaks and bullfinches

At the end of last year I made several bird feeders, among them two bigger wooden models for seeds. It took some time until I finally managed to instal one of them in the garden, but the birds quickly learnt to use it. I was especially delighted when I discovered that two pairs of grosbeaks had also discovered the sunflower seeds. I don´t remember when I´ve seen grosbeaks the last time, but it was surely several years ago, what made it even better to see those impressive birds from close distance.

Grosbeaks  or hawfinches (Coccothraustes coccothraustes) are the largest members of the finch family Fringillidae at Europe. Their highly specialized massive beaks are even strong enough to crack open plum and cherry seeds, what enables them to exploit food sources unaccessible for most other birds.

DSC03206

The inside of the upper beak is equiped with five cutting edges, three median and two lateral ones and  grooved surfaces in the distal half of the beak, which correspond to a pair of knots in the lower beak.

Another species which regularly dines at the bird feeder is the bullfinch (Pyrrhula pyrrhula), another large member of the Fringillidae. The males have strikingly read plumage and are undoubtedly among the most beautyful European songbirds.

DSC03213

Compared with the greenfinches, chaffinches and sparrows in the garden the bullfinches look pretty big, but next to the bulky grosbeaks even they seem delicate.

DSC03211

A female bullfinch, which is of much lesser spectacular colouration than the male.

DSC03218

This bird feeder works really quite good, and possibly I will write a blog post about its construction.

Veröffentlicht unter Vögel | Verschlagwortet mit | Hinterlasse einen Kommentar

The remarkably big caudal keels of swordfish

That´s just another of those posts which focus on lesser known anatomical oddities in otherwise better known animals. This time it´s about one of the most iconic teleost fish, the grand swordfish Xiphias gladius.

But I won´t cover its most prominent attribute, the highly elongated rostrum, but take instead a look at the other end of the body. Depictions of swordfish in books are usally in a lateral view, as are most photos. As a result of this, the horizontal shape of the body is hardly recognizable. When I was last year at the island of Corfu (Greece), I had the chance to take a photo of a tail end of a swordfish when I visited a fish market. At this perspective, you can see very well how wide and robust the tail actually is, and how strong and massive the locomotory caudal muscles really are.

But even more surprising was the sheer size of the lateral keels near the caudal fin. This keels are often mentioned in books about fish, but they look only quite unremarkable on typical illustrations in lateral view.

Schwerfisch caudal Korfu

Swordfish tail with prominent lateral keels, photographed at Corfu.

This keels are unique among Istiophoriformes, all the other species like marlins or sailfish – which belong to the distinct genus Istiophoridea – have instead a vertical row of two pairs of lateral keels.

This keels act as stabilizers during swimming, and also occur in comparable shapes in other fast-swimming pelagic fish like mako sharks.

Veröffentlicht unter Fische, Megafische | Hinterlasse einen Kommentar

The oral oddities of ruminants

In the last post I wrote about the strange anatomical structures in the beaks of spoonbills. This time I will cover again oral oddities, but in a fully different class of animals. Ruminants have always been among the most important game for humans, and in the form of their domesticated varieties among the most important animals in the history of mankind. Sheeps, goats, various domestic bovines and domestic reindeers were essential elements of whole cultures, and even today huge industries are build on some of them.

So it is not surprising that we normally do not think of anything really weird when we look at those animals. That´s probably in part because we usually don´t come really close enough to them, but also because most of us usually don´t butcher or dissect them ourselves.

But if you do so, you can find anatomical structures of nearly alienesque weirdness. If you have seen photos of the mouth cavities of leatherback turtles (Dermochelys coriacea), you will know about those totally crazy spine-covered papillae which help them to engulf such slippery prey like jellyfish, and which also line the whole length of the esophagus (actually Dermochelys isn´t the only marine turtle with such papillae, only the most famous one to have them).

But as grotesque as those spinous papillae of leatherback turtles seem, they aren´t even that different from very similar structures found in the mouth cavities of ruminants like for example ordinairy domestic cows or sheep. One good way to see them in all their strangeness, is to dissect a ruminant head,. That is a great possibility to see even the normally not visible parts inside the mouth, and all the extent of the oral papillae.

But sometimes you can also have the chance to see them in a living animal. Last year I visited the wildlife park Wildparadis Tripsdrill, a really very nice park with a very large number of interesting animals, mainly from the Northern hemisphere. Many of the ungulates there are used to eat the pellets which are sold for visitors. Besides various deers, muntjaks, mufflons and some other ones, there are also domestic yaks (Bos grunniens), which are eager to beg for pellets.

DSC02829

Subadult yaks at Wildparadis Tripsdrill

Now let´s look into their mouths.

DSC02822

Closer.

DSC02826

Even closer:

DSC02826 a

The whole insides of the cheeks and some other, in this photo not visible areas, are covered with weird tentacle-like villi. They are directed towards the gullet, and form together with the much smaller papillae on the tongue a conveyer system for plant matter.

Another photo taken from the side:

DSC02827

Besides several still not fully grown subadults, there was also a highly impressive bull, which was also quite willed to show the inside of its mouth.

DSC02861

The bull had also really formidable horns and striking elongated dorsal spines.

DSC02860

Even given the fact that domestic yaks don´t grow as big as their wild relatives, this bull was still a highly powerful and beautyful being.

DSC02869

And it had a nice white beard as well.

DSC02872

Those villi are more or less soft, but some of them, in particular those in the lower corner of the mouth, have well pronounced keratinized tips which extends into short spines.

Unbenannt

And what looks at that perspective nearly like some alien slug radula is still only a quite normal bovine mouth.

DSC02875

The tongues, cheeks and other elements of the oral cavities of many animal are highly specialized, sometimes even extremely grotesque by human standards, but they usually still don´t get much attention.

Veröffentlicht unter Anatomie, Säugetiere | 1 Kommentar

Birds with weird beaks part III: Why spoonbills are even stranger than you think

Spoonbills (Plataleinae) have obviously weird beaks. The overall elongated shape with the flat and proximally widened end is already a quite strong modification of the „normal“ bird beak. But you have to take a really close look at the beak, to see another, much lesser obvious anatomical feature, which makes it even more bizarre.

If you take for example the Eurasian spoonbill (Platalea leucorodia), a bird of quite exotic appearance which surprisingly even breeds in low numbers in great Britain, Denmark and Germany. The proximal half of its beak is nearly absurdly thin and flat, with the epynomous spoon-shaped end. That´s what people usually look at and immediately know why it´s called spoonbill.

Eurasian spoonbill (Platalea leucorodia), ornithological museum at Rocca di Lonato

When you look however in the distal part of the beak, you won´t not only notice some fine transverse ridges on the upside and margins of the beak, but also some strange keratinous structures at the inside.

Eurasian spoonbill(Platalea leucorodia), ornithological museum Rocca di Lonato (2)

And that´s how they look in a more lateral view:

Eurasian spoonbill(Platalea leucorodia), ornithological museum Rocca di Lonato (7)

I made another photo without flashlight, to make it somewhat more contrasty.

Eurasian spoonbill(Platalea leucorodia), ornithological museum Rocca di Lonato (4)

And for comparison one with flashlight:

Eurasian spoonbill(Platalea leucorodia), ornithological museum Rocca di Lonato (5)

That´s it, there are numerous conical peseudoteeth-like processes inside the beak. They are easily overlooked from the distance or from other viewing directions. That´s one reason I  really enjoy looking at museum specimens, because you can often see tiny anatomical details you can rarely see in a moving and usually more distantly located living animal.

I tried to make another photo to get a shot of the keratinous cones in the upper beak:

Eurasian spoonbill(Platalea leucorodia), ornithological museum Rocca di Lonato (8)

That was part III of the weird bird beak series, which I hope to continue anytime. But I think I´ll make a break now to write the next blogpost about something different.

Veröffentlicht unter Anatomie, Vögel | Hinterlasse einen Kommentar

Weird bird beaks part II: The pseuodeteeth of the double-toothed barbet

Today´s featured bird with a weird beak is the double-toothed barbet (Lybius bidentatus), a colourful member of the African barbets, and around the size of a sparrow.

Lybius bidentatus (1)

Double-toothed barbet (Lybius bidentatus) taxidermy specimen from the Zoological Insitute Tübingen

The origin of their name is quite obvious, as their upper beaks shows some pretty big pseudotooth-like projections.

Another photo showing the whole taxidermy specimen:

Lybius bidentatus (2)

.

Veröffentlicht unter Anatomie, Vögel | Hinterlasse einen Kommentar

Weird bird beaks part I: Frontal shield beaks in violet turacos

This is meant as some sort of mini-series to feature some lesser known birds with weird beaks. Perhaps I will also include some birds which seem more familiar, but whose weird beak features are usually missed.

I start with the violet turaco (Musophaga violacea), a member of the diverse turaco family from tropical and subtropical Africa. In this birds the beak extends in a bulbous shape over the frontal skull area and forms a contiunous shield like structure.

Violet turaco (Musophaga violacea) at the Zoological Institute Tübingen

Violet turaco (Musophaga violacea) at the Zoological Institute Tübingen

If you take a close look, you can also see small serrations in the anterior part of the upper beak.

518px-Musophaga_violacea-20080321

Violet turaco from Wikipedia

Veröffentlicht unter Anatomie, Vögel | Hinterlasse einen Kommentar

A tiny lindworm with huge hidden teeth and bone-armoured skin – The slow worm, largest lizard of Northern Europe

Central and Nothern Europe is not particularly rich in reptiles, and many of the native species are even quite rare and occur only quite locally restricted. In Germany for example, there are only around 13 species, among them five (or possibly six, with an obscure local population of Iberolacerta horvathi in the Northern Limestone Alps) species of lizards, six species of snakes (of which three have only very small to tiny distribution areas) and the European pond turtle Emys orbicularis, which is also nearly fully extinct here.

There is also another one, which is among my favourite native reptiles, the slow worm Anguis fragilis. Besides sand lizards and wall lizards, which are comparably common and numerous in certain areas, they are the only native reptiles I see at least moderately often, yet still only on occasion.

Slow worm Anguis fragilis

Slow worms are fascinating for many reasons. First of all, they have one of the largest geographical ranges of all reptiles, from the most southern areas of Italy up to northern areas of Sweden and Finland, only surpased by the viviparous lizard Zootoca viviparia.

Population range of Anguis fragilis from Wikipedia

One reason why they can occur even in very cold areas is probably because they are ovoviviparous, so pregnant females can follow the sun and in this way boost the growth of the embryos, even in areas with short summers.

Slow worm juvenile

Besides wall lizards, which sometimes live even right into towns (like an allochthonous population from Northern Italy which lives around the castle of Tübingen and some other areas in the town) and sometimes sand lizards, slow worms are also nearly the only native reptiles here which are sometimes living in comparably densely populated areas. I knew a population which lived (or still lives) in a housing area which had besides some small gardens and hedges next to no green areas, only one small building ground of perhaps 25 x 20 m covered with grass and blackberry.

Blindschleiche Korfu

A slow worm I photographed in a semi-urban area at Korfu, Greece.

Slow worms are – as you might imagine form their name – not very fast. They often wiggle in a very stiff and somehow clumsy way, very unlike snakes. The reason for this is not externally visible, but becomes more evident if you touch a slow worm. They feel quite hard, because their whole body is covered by small round osteoderms, which are below the scales. This osteoderms are connected comparably tightly with each other, and can even still preserve the external shape of a dead slow worm, when all soft-tissue inside has already broken down or was eaten away by scavenging insects.

Some years ago I found a half slow worm on a sidewalk next to a garden, perhaps killed by a cat or road-killed by a bike. Some of the scales around the head were lost, and the body shape was somewhat distorted from shrinking, but it was still not very different from those of a living slow-worm, besides being fully hollow at the inside. I have also a 3D X-ray scan of this specimen made via cone beam computed tomographie, but stupidly I had the data not available on my PC when I wrote this blog entry.

DSC03005

Mummified slow worm

Last year I also found a piece of a slow worm on a concrete blog at my garden parcel, possibly placed there by a cat. It had been lying there for quite a while, and it had been warm and rainy for some time, so parts of the scale-armour-like skin areas disarticulated and isolated round osteoderms became visible.

Anguis osteoderms

Close up of the osteoderms:

Slow worm osteoderms detail

When dead slow worms break down and the scales fall off, you can´t only see those cool osteoderms, but also another rather unsuspected anatomical feature, nasty teeth like tiny curved daggers. Compared to the size of the skull, those teeth are really huge, proportionally well bigger than those of komodo dragons or mosasaurs for example. But you still can´t see them in live slow worms, because they have -like all squamates – well developed lips which cover their teeth. Keep this in mind the next time you see a reconstruction of a mosasaur or Megalania with well visible teeth. That´s not realistic, they had surely like all other squamates lips which covered their teeth, so they were nearly not visible when the mouth was open, and there is no good reason to think it was different in those extinct lineages.

Another, already quite decomposed dead slow worms I found. Those teeth are really nasty.

DSC09619

The other side of the head:

DSC09624

Again a close up of the first mummified specimen. It´s really very very hard to get good photos of this tiny anatomical details, as the whole skull is well under a centimetre in length.

DSC03008

So, for what are those sting-like teeth good for? Slow worms feed mainly on soft-bodied invertebrates like small slugs and earthworms, and the long pointed teeth help to hold slithery prey covered in mucus. I once observed a slow worm eating a huge earthworm which was nearly equal in body diametre and I was really surprised how it was slowly devoured. On occasion they also consume other small invertebrates, whereas predation on other reptiles is extremely rare. There is only a small handful of documented cases in which other reptiles were eaten, like for example small sand lizards or other small slow worms. Here is a photo of such a rare event, an adult slow worm devouring a juvenile of its own species (photo from Wikipedia):

Slow worm cannibalism (from Wikipedia)

Slow worm cannibalism (from Wikipedia)

Besides for catching slugs and worms, the long teeth are also used in comment fights between males and during the mating rituals, in which the males bite the females in the head or neck area. Another photo from Wikipedia showing this behavior:

Male slow worm biting female. You can also see very well the difference of the non-autotomized tail of the male and the shrt re-grown tail of the female on the left.

Male slow worm biting female. You can also see very well the difference of the non-autotomized tail of the male and the short regenerated tail of the female on the left.

As a result of this rigorous use of the teeth, some specimens show severe skin-scarring. The scratches on this very large dead-found slow worm are also possibly the result of intraspecific bites, yet I doubt it was the reason why it died, as the scratches are not very deep.

PICT1299

Furthermore, the osteoderms should reduce most damage to superficial skin injuries, and I already wondered if this armoured skin is possibly mainly a defense against the teeth of other slow worms, and to a lesser degree a defense against predators. In sharks females have also usually a much thicker skin than males, because they are often bitten by the males while mating. I also doubt that even this tough skin armour has that much effect against most predators at all, given the very large number of animals which prey on slow worms. The teeth of hedgehogs and small carnivores are well capable to deal with this kind of armour, and it´s also no very effective defense against birds of prey, storks or other larger potential slow worm predators. Nor does it seem to help much against smooth snakes (Coronella austriaca), which are -where they occur in the same area- important predators of slow worms. This surely doesn´t mean the osteoderms have no defensive function against predators at all, but it´s possibly only one of several functions.

Autotomie however seems to play an important role in self-defense, and a large number of slow-worms have regenerated tails. Here is a photo of a freshly autotomized tail I found at my garden parcel, which was still moving at that time.

DSC03183

If you take a close look you can even see the different muscles at the base of the stump:

DSC03182

Another photo of a specimen which obviously lost its tail only a short time before.

DSC07380

Close up of the stump. You can also see where the slow worm was grabbed by a predator:

DSC07378

The species name fragilis already indicates the autotomizing behavior of slow worms. I once found a roadkilled juvenile slow worms which apparantly autotomized in death agony its tail on multiple areas.

PICT0130

Most slow worms are somewhere between 25 and 35 cm, what also depends on the nature of the tail of course, as regenerated tails are often much shorter than the original tails. Some slow worms can however sometimes grow considerably larger. Several years ago I found a monstrously huge specimen during a walk in a vineyard area. It showed no external injuries, only the eyes had already dried, but it had some blood around its nostrils, what could indicate intoxication of some sort, perhaps as a result of insecticides or molluscicides used in the area. Because of its big size and unusally good condition I took it for my collection to store it in a jar with alcohol. It was already quite stiff, so I could not straighten it for a good measurement. Instead I used a piece of thread to measure over the curve of its body. I was highly surprised when I realized the thread was hardly long enough, even more so when I found it was 45 cm in length. This measurement was made quickly and I did not follow the curve of the body that exactly, what resultet in some underestimate of the length. When I later made another measurement with a longer thread and a more exact following of the curves, I came to an incredible 48 cm. That is truely huge, as long as my arm (without the hand).

PICT0066

Dead monster slow worm

Here again a photo of the preserved monster specimen:

Riesenblindschleiche dorsal

At that size it was already bigger than every other species of lizard here, even the two species of green lizards hardly reach lengths of 40 cm, but usually stay well shorter. To be fair, their heads and bodies are still somewhat bulkier than those of slow worms. By chance there actually is a very cryptic population of green lizards in that which was just officially verified last year in the area where I also found the giant slow worm. I was quite lucky to discover one of those green lizards and take some very first photos of it.

Another large yet not giant dead-found specimen of 41,7 cm:

Giant 2

Here is a specimen which is more in the upper average range, photographed several years ago with my old mobile phone I had at that time.

PICT8614

I have seen some few specimens of similar sizes as the „monster“ in museum collections like at Copenhagen, Berlin and Vienna, and there are some other specimens on record which actually exceed a full half metre in length. The discovery of an extremely exceptional specimen was published in 2012 in the journal Zeitschrift für Feldherpetology (journal of field herpetology) by Wolfgang Böhme. This particular specimen had a length of 57, 5 cm, what is by the standards of its species truely gargantuan, nearly a small real-life lindworm.

I think it is somewhat erroneous to think that such outsized specimens have to be unusually old. A lot of people are under the impresseion that reptiles, fish and amphibians grow for their whole life and can therefore (theoretically) reach every size. But in reality, that´s a massive simplification to say it at least. First of all the growths of different species can differ highly. Especially many smaller species have more or less determinate growth and most adult specimens in a population have quite similar sizes, independent of age. Some species grow for a longer time and gain even after reaching sexual maturity for some time additional length, sometimes for many years. But even then, growth usually decreases considerably, and the proportional length growth in later years is normally very low or even next to absent. An exceptionally big specimen was most probably already quite big at early age when unusually strong growth had the strongest effect. Of course big size can be an advantage, for example when it is an advantages against predation, what can facilitate over-average life-spans of those specimen. But on the other hand, there will be specimens which never reach exceptionally big sizes, even after many decades.

DSC07389

And slow worms can actually live for many decades. Besides certain testudines and crocodylians, slow worms have one of the longest recorded life-spans of all reptiles. They can reach an age of 46 years at least, and a specimen which was once kept in the Copenhagen Zoo was said to have lived there for 54 years.

Another little known fact about slow worms is that they can be surprisingly colourful. In general they are of mainly greyish, coppery or brownish colour, sometimes with some patterns in the head and neck area, which his often more pronounced in juveniles. Especially juveniles have also often a dark dorsal stripe and often a more marked colour difference between dorsal and ventral sides.

That´s another dead slow worm I found (still fully flexible and without any injuries, possibly another one which died from intoxination):

DSC04257

Note the compass with included ruler, this little gadgets are extremely handy and useful to take photos with size comparisons.

The ventral side in this specimen was nearly fully jet-black, what´s also not that common:

DSC04259

But some specimens have also bright blue scales as well. The amount of those blue scales can vary significiantly, sometimes there are only some few and isolated ones, sometimes the spots are all around. I´ve seen so far only two specimens with pronounced blue scales, one of them was a roadkilled specimen which I fond only a few metres next to the monster specimen.

PICT0061

Population screenings in Northern Italy showed that only lesser than 0,8% of the whole slow worm population possess those blue scales, which are usually mainly found in older males. In the related Anguis colchica they are more common, with blue scales occuring even among females, and there is even a specimen on record which had a fully blue belly.

DSC03236

Juvenile specimen with marked colour contrast between lateral and dorsal area.

I wrote this blog-post especially for those non-European readers who aren´t familiar with slow worms, but also of course for all other people which have slow-worms around. The next time you see one, keep in mind how awesome and fascinating this little lindworms are.

Veröffentlicht unter Naturbeobachtungen, Reptilien | 5 Kommentare