HE has known a spectacular variety of mammalian carnivores since the late Paleocene. Spec on the other hand, seemed to have continued dinosaurian and crocodilian dominance throughout the entire Paleogene. Nevertheless, an abundance of small insectivorous and carnivorous mammals have been recovered from fossils. They belonged to an astonishing diverse array of clades. Within Eutheria alone, weasel and fox like furballs abounded. Cimolestans and zhelestids and within Placentalia, actual stem carnivorans and even possibly mesonychids. Among insectivorous mammals, many different groups apparently strived for dominance.
However, by the Neogene, it seemed that the metatherians would become the dominant mammalian carnivores of Spec, however limited that niche was. Four clades, the pusillonecatoridea, the suchotheriidea, the stagodonta and the esurimalaidae are presently known. While molecular analysis nest them together to the exclusion of other metatherians, they are clearly very distant from each other. This extends far back into the late Cretaceous, when close relatives of each clade were present.
The working theory at the moment is that all four clades are derived members of deltatheroidia. While the molecular analysis can only deal with the living deltatheroidians, morphological comparisons of both living and fossil examples of the clades can give more clues. So far, all four members are aligned with predecessor forms. However, they generally fall outside of them as sister groups in most respected character analysis.
However the final tally plays out, these interesting critters are noteworthy just for their ecological effects on Spec. They’ve been the primary terrestrial carnivores under 10 kilos across the Holarctic and into the Paleotropics since the late Miocene. The arrival of the Ice Age has seen them spread into South America (where they face the necobataarids).
The Possum Weasels and Badgers *Pusillonecatoridea*
This clade developed by the late Eocene. The seismonychidae have achieved great success as burrowers and badger analogues. The pusillonecatorids have crowed as mustelid analogues.
Tarkas, Fitches, Vairs and Snoats *Pusillonecatoridae*
Widespread throughout Spec, the pusillonecatorids fill the niche that is otherwise occupied by the mustelids on HE. They are quite common and successful small predators, and are often themselves prey for larger carnivores.

(Pictures by Timothy Morris. Descriptions in descending order)
The notabrock *Parametameles apates* is a pusillonecatorid trying very hard to be a brock. Unlike its Holarctic relations, the notabrock can be found in Africa, and is more closely related to the weasel-like pusillonecatorids than the badger-like seismonychids. At any rate, its habits and behavior are sufficiently badger-like: it is an indiscriminate omnivore, and also has a sweet tooth that attracts it to bacchus-tree fruit drops.
The short-tailed vair *Metamustela nivalis* and its relatives are the closest on Spec to weasels. Aggressive and deadly little hunters, they will prey on animals substantially larger than themselves by going for the throat and clinging on till death ensues. Despite their ferocity, they commonly fall prey to avisaurs, kronks, scowls, pokemures, and even their own kind.
North America's Great Plains is home to large groups of Laccolithons *Geodeltatherium grecoi*. Living socially in groups, these pusillonecatorids move into uplift glyphon burrows and take them for their own purposes. Despite the presence of the large lizards, neither of the two species seems to ever enter into conflict, with only the occasional squeak betraying the collision of an industrious glyphon into a resting laccolithon. While the glyphons expand the burrows, the laccolithons, with their sharp eyes, keep a watch for predatory animals by sitting upright. As the lizards feed on insects and the deltas forage for vertebrate prey, competition is duly avoided.
The Montezuma *Montezumustela striata* can be found throughout South America as a generalist arboreal hunter. Fast and agile, montezumas use their quick reflexes to dash at top speed between tangles of otherwise inextricable branches. They will prey on lizards (including the ponderous treeguanas), snakes, birds, and mammals, and regularly raid treetop nests. Montezumas are quite fearless and will follow prey to the tips of the flimsiest twigs, relying on a catlike aptitude to survive falls. They are one of the very rare few possum weasels to have invaded the realm of the death multis.
Williamson's tarka *Tarka williamsoni* is the best known of a group of pusillonecatorids that approximate otters. Found from the British Isles to the Mediterranean, Williamson's tarka is a highly adaptable amphibious animal that will eat almost anything, is an agile swimmer and a quick sprinter, and is as much at home up a tree as it is in a river or the sea. Tarkas have been observed diving to great depths to snatch shellfish and garbargee eels. The whistle of a tarka ("Ic-yang!") is very distinctive, and is often heard before the animal is actually seen.
The Northern fitch *Pseuderminea mustela* and other fitches are the stoats to the vairs' weasels. Fitches are larger than vairs and feed on even larger prey with the same throat-bite, but lack the hair-trigger temper and irascible attitude of their smaller relatives. Fitches are relentless trenchermen, and spexplorers have often appreciated their propensity for eradicating xenos, even the repulsive naked sweat mice. It is likely that they would make excellent pets and companion animals for humans, but no-one has bothered to try domestication yet.
The waistcoat deltamandua *Bicoloripelta africana* can be found in African savannah and scrub. A ground-living generalist, it has a fondness for insects, especially social insects. Termite mounds, anthills, and bee's nests are favorite haunts, and it guzzles the insects down with glee. A thick pelt with unusual, "waistcoat" markings provides ample protection from bites and stings. Deltamanduas have strong digging claws on their hind legs which they use to break into nests, and to defend themselves by kicking backwards.
Natives to Europe's coastline, the channel snoats *Pusillonecator myxinis* are scavengers and beachcombers, nimble little opportunists that feed on the smorgasbord of food to be found on Spec's bountiful shore. A small, lithe body allows snoats to skitter between rocks and ferret out food, which includes mollusks extracted daintily from their shells, fish gaffed neatly from the water, and seabird eggs taken in pairs – one snoat distracts the parent while the other gluts itself. Snoats are also invaluable scavengers, crawling into a dead animal to devour it from the inside out. Other species of snoat can be found on riverbanks, in forests, and on the high alpine peaks.
The pastinaca *Obnoxiotherium pastinaca* is a large, omnivorous Asian jungle beast. Its brightly colored and striped pelt, and foul stench, fully advertises its nasty defense to predators. If attacked, a pastinaca arches its hindquarters over its back in a spectacular feat of contortionism, and fires at its attacker's eyes with a noxious fluid ejected from glands in the anus. Whether this fluid is manufactured by the pastinaca, or is synthesized from the toxic plants that the pastinaca feeds upon, is still a matter of conjecture. The pastinaca itself has no problem guzzling virulent fruit, not to mention a wide range of small prey.
Other pusillonecatorids include the wabassos *Metamartes*, a strictly American radiation with several species. Some poorly known African rainforest species are still being evaluated as of this writing. There are also three recently collected specimens from the Eurasian taiga that may represent new species or even genera.
Brocks and Allies *Seismonychidae*
The seismonychids, or Spec-badgers, are deltatheres clearly distinguished from their pusillonecatorid relatives. While the pusillonecatorids are small weasel-analogues, the seismonychids have expanded into the burrowing and digging niches. Seismonychids are widespread over the globe in various badger, mole, and desman roles.
(Pictures by Timothy Morris. Descriptions in clockwise order)
The bloody bill brock *Metameles sanguineus* is the largest and most distinctive member of the family. Males may occasionally reach 30 kilos. A European species, this massively built omnivore will eat everything it can get at. Pretty much anything that moves is fair game, but there is no shame in munching on berries. Bloody bill brocks are tough fighters and relentless diggers, and have few enemies in the wild. The related timmy and tommy brocks are smaller and less aggressive.
Shatterlogs comprise a compact genus of semi-amphibious brocks. Distinguished by naked and webbed hind feet, shatterlogs dig burrows on riverbanks, and use them as a base from which to hunt frogs, fish, and other small animals. The burrows are quite complex, and can never be totally flooded. A parent shatterlog will dart out of its burrow at startling speed if it feels its offspring to be menaced. These relentless predators often use gnawed and broken branches to mark territory, hence the name. Pictured here is an American bank shatter log *Fluviomeles jacquesi*.
The largest subdivision of the Seismonychidae is the Plissorhyninae, known as schnozzles. These animals have a unique and unmistakable nose: bare-skinned up to the forehead, large, drooping, and heavily wrinkled. The wrinkles increase surface area massively both inside and out: externally, they provide more tactile surface, while internally they allow more space for sensitive chemoreceptors. The snout is highly flexible and exploratory, and a full complement of whiskers rounds out the sensory array. Plissorhines may have the most powerful olfactory and tactile senses in Class Mammalia. At any rate, the nose must be the key to their success – members of this family outnumber other seismonychids three to one in both number of species and diversity.
The girdled schnozzle *Rhinotalpa hemicincla*, shows usual plissorhine adaptations: powerful digging legs, weak back legs, and the diagnostic wrinkled snout. In this species, the snout-pad does not reach up to the forehead. While this was previously seen as a primitive trait, it is now being reconsidered as a schnozzle moving up and out. Girdled schnozzles are water-loving and less subterranean than the rest of their group.
The silver schnozzle *Plissorhinus argyrus* is a typical schnozzle. Filling in the mole niche in temperate to cold areas (glyphons are dominant in warmer climes), the silver schnozzle digs extensive tunnel networks to seek out small invertebrates and the occasional lizard. Its fur gleams silvery in light, which is hardly ever seen as it spends almost all its time underground.
Florida schnozzles *Riparitalpa floridiana*, as their name implies, may be found in Florida, but then they are widespread in various marshy environments. Larger and more powerful than most schnozzles, these hardy beasts build and shore up riverside holes from which they continue excavating. They are good swimmers and have been known to feed on fish.
Pack-noses *Pachynasotherium troglodytes* are primarily desert dwellers. Living in holes excavated in rock crevices, these tough schnozzles come out at night to feed on insects and to gather grass and leaves to line their nests. They are tasty snacks for countless other desert animals – mattiraptors, avisaurs, vipers, small draks, kronks, larger metatheres…
The edible schnozzle *Nasotupaia glis* was unfortunately named after an early spexploring expedition, on the verge of starvation, survived by feeding on these abundant little creatures. These creatures stand out from the rest of their family as tree-climbing, agile schnozzles. Like the rest of their family, they come out only at night, and use their nose to ferret out prey.
Crevice-runners *Lithotalpa hirsuta* are found in the karst habitats of Eurasia, acting much like rock hyraxes. Again, they are indefatigable burrowers, tunneling during the day and emerging by night. The bristles and whiskers on the face are particularly well-developed, to aid it in making its way through a treacherous maze of sharp rocks and gaping holes.
Winged moles *Pterotalpa musculus* were once considered cryptid jokes, but recent discoveries have proved their existence. These schnozzles have enormous arms (almost wings) that practically dwarf the rest of their body, and as such are powerful burrowers. The hind legs are just about vestigial, and winged moles rely solely on their arms to pull them through the earth.
The masked ranger-mole *Personatalpa kemosabei* is a non-plissorhine trying very hard to be one. The snout is bare at the tip and slightly wrinkled, and it functions in much the same way, but any resemblance between this brock and the schnozzles is purely convergent. In addition, ranger-moles are much more active, and may cover large distances by night in search of prey. By day, they sleep in excavated burrows. This species is native to the American Southwest. It may be identified by its odd chuckling growl, transliterated by imaginative spexplorers as “tu-de-dum, tu-de-dum, tu-de-dum-dum-dum…”
Another well known seismonychid is the Grumbler *Thylodachius saskatchwannensis*. They are quite powerful critters, these 12 kilo diggers are mostly diurnal hunters of the prairies and dense eastern forests. Multis and glyphons live in mortal fear of these determined burrowers. The savage disposition of these critters is well known. Grumblers have incredibly thick yet flexible hides with stiff fur that allows them to turn completely around a tight corner underground.
posted by Raymond @ 10:59 PM
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