Tambachia
Encyclopedia
Tambachia is an extinct genus
of dissorophoid
temnospondyl within the family
Trematopidae. It is known from the Early Permian Tambach Formation (the lowermost unit of the Upper Rotliegend
) near the town of Tambach-Dietharz
in Thuringia
, Germany
. Tambachia is the first trematopid to have been discovered outside the United States
.
specimen of Tambachia trogallas, known as MNG 7722, has been found from an outcrop of the Tambach Formation at the Bromacker locality in the Thuringian Forest
of central Germany. It consists of a skull and much of the postcranial skeleton. The only major portion of the skeleton that is missing is the presacral vertebral column. The Bromacker locality is a sandstone
quarry
that is well known for tetrapod
trackways
and articulated skeletons of terrestrial and semiterrestrial amphibian
s and reptile
s. MNG 7722 was found in red-bed fluvial
deposits consisting of well consolidated
mudstone
s in flat-bedded channel fills.
Although it is difficult to determine the maturity of MNG 7722, it is thought to be an early adult. Poor ossification
of the carpals, tarsals
, and endochondral portion of the braincase suggest that MNG 7722 represents an early stage of development, while the pitted skull roof
, with tightly closed sutures between bones, indicates a mature individual.
The name Tambachia refers to the Tambach Formation. The specific name of T. trogallas is derived from the Greek
trogo, meaning munch or nibble, and allas, meaning sausage
. The name refers to the Thuringian bratwurst
that was frequently eaten in the Bromacker Quarry by the authors who described the species.
, or eye sockets, are centrally placed so that the preorbital length of the skull is equal to that of the postorbital length. They make up around 30% of the skull length. The skull table seems to extend posteriorly past the level of the jaw articulation in Tambachia, which is unique among trematopids. However, this is likely to have been the result of crushing of the skull, which displaced the skull table.
Tambachia, like other trematopids, likely possessed a salt gland
similar to those seen in modern reptiles. The subdivision of the external naris
into anterior and posterior portions is evidence of the presence of salt glands. The anterior portion is sub-circular and is thought to be the true narial opening. The posterior portion likely held the salt gland. The expansion of the posterior portion may not be an accommodation for the salt gland, but rather a means of coping with cranial stresses during feeding.
The postcranial skeleton is well known in Tambachia, given the completeness of the holotype specimen. The relatively short tail, preserved only as a faint impression in MNG 7722, is 8.5 centimetres (3.3 in) long. The limbs are short, with four digits on the manus
, or hand, and five digits on the pes
, or foot. It is possible that the manus possessed five digits, since Acheloma
, another closely related trematopid, has been described as having five distal carpals. In the pes of the holotype specimen, there are only four digits preserved. However, since the third preserved digit is the longest, it likely represents the fourth digit, with the first digit absent due to imperfect preservation. The terminal phalanges of Tambachia were narrow, and would have been the core supports of claws.
was the closest relative of Tambachia. Characteristics that supported this relationship included the absence of an internarial fenestra (which is also seen in dissorophids
, but was interpreted as a convergent
trait), the reduction of the suborbital process of the lacrimal
, and a contribution to the ventral orbital rim (the rim of the eye socket) by the maxilla
rather than the palatine
. Below is a cladogram
modified from Sumida et al. (1998) showing the proposed relationships of Tambachia and other trematopids:
In their description of Fedexia
, Berman et al. (2010) placed Fedexia as the sister taxon of the clade containing Tambachia and Anconastes. Tambachia, Anconastes, and Fedexia all possess a shallow and broadly concave occipital
margin. In other trematopids, the margin is biconcave. Below is a cladogram modified from Berman et al. (2010):
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of dissorophoid
Dissorophoidea
Dissorophoideans are a clade of medium-sized, temnospondyl amphibians that appeared during the Late Pennsylvanian in Euramerica, and continued through to the Late Permian and even possibly the Early Triassic of Gondwana...
temnospondyl within the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Trematopidae. It is known from the Early Permian Tambach Formation (the lowermost unit of the Upper Rotliegend
Rotliegend
The Rotliegend or Rotliegendes is a lithostratigraphic unit of Cisuralian age that is found in the subsurface of large areas in western and central Europe. The Rotliegend mainly consists of sandstone layers...
) near the town of Tambach-Dietharz
Tambach-Dietharz
Tambach-Dietharz is a town in the district of Gotha, in Thuringia, Germany. It is situated in the Thuringian Forest, 19 km south of Gotha.- Places of interest :...
in Thuringia
Thuringia
The Free State of Thuringia is a state of Germany, located in the central part of the country.It has an area of and 2.29 million inhabitants, making it the sixth smallest by area and the fifth smallest by population of Germany's sixteen states....
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
. Tambachia is the first trematopid to have been discovered outside the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Discovery
The holotypeHolotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
specimen of Tambachia trogallas, known as MNG 7722, has been found from an outcrop of the Tambach Formation at the Bromacker locality in the Thuringian Forest
Thuringian Forest
The Thuringian Forest running northwest to southeast, forms a continuous stretch of ancient rounded mountains posing ample difficulties in transit routing save through a few navigable passes in the southern reaches of the German state of Thuringia. It is about long and wide...
of central Germany. It consists of a skull and much of the postcranial skeleton. The only major portion of the skeleton that is missing is the presacral vertebral column. The Bromacker locality is a sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
quarry
Quarry
A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...
that is well known for tetrapod
Tetrapod
Tetrapods are vertebrate animals having four limbs. Amphibians, reptiles, birds and mammals are all tetrapods; even snakes and other limbless reptiles and amphibians are tetrapods by descent. The earliest tetrapods evolved from the lobe-finned fishes in the Devonian...
trackways
Ichnite
An ichnite is a fossilised footprint. This is a type of trace fossil. Over the years, many ichnites have been found, around the world, giving important clues about the behaviour of the animals that made them...
and articulated skeletons of terrestrial and semiterrestrial amphibian
Amphibian
Amphibians , are a class of vertebrate animals including animals such as toads, frogs, caecilians, and salamanders. They are characterized as non-amniote ectothermic tetrapods...
s and reptile
Reptile
Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...
s. MNG 7722 was found in red-bed fluvial
Fluvial
Fluvial is used in geography and Earth science to refer to the processes associated with rivers and streams and the deposits and landforms created by them...
deposits consisting of well consolidated
Compaction (geology)
Compaction refers to the process by which a sediment progressively loses its porosity due to the effects of loading. This forms part of the process of lithification. When a layer of sediment is originally deposited, it contains an open framework of particles with the pore space being usually...
mudstone
Mudstone
Mudstone is a fine grained sedimentary rock whose original constituents were clays or muds. Grain size is up to 0.0625 mm with individual grains too small to be distinguished without a microscope. With increased pressure over time the platey clay minerals may become aligned, with the...
s in flat-bedded channel fills.
Although it is difficult to determine the maturity of MNG 7722, it is thought to be an early adult. Poor ossification
Ossification
Ossification is the process of laying down new bone material by cells called osteoblasts. It is synonymous with bone tissue formation...
of the carpals, tarsals
Tarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...
, and endochondral portion of the braincase suggest that MNG 7722 represents an early stage of development, while the pitted skull roof
Skull roof
The skull roof , or the roofing bones of the skull are a set of bones covering the brain, eyes and nostrils in bony fishes and all land living vertebrates. The bones are derived from dermal bone, hence the alternative name dermatocranium...
, with tightly closed sutures between bones, indicates a mature individual.
The name Tambachia refers to the Tambach Formation. The specific name of T. trogallas is derived from the Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
trogo, meaning munch or nibble, and allas, meaning sausage
Sausage
A sausage is a food usually made from ground meat , mixed with salt, herbs, and other spices, although vegetarian sausages are available. The word sausage is derived from Old French saussiche, from the Latin word salsus, meaning salted.Typically, a sausage is formed in a casing traditionally made...
. The name refers to the Thuringian bratwurst
Bratwurst
A bratwurst is a sausage usually composed of veal, pork or beef. The plural in German is Bratwürste....
that was frequently eaten in the Bromacker Quarry by the authors who described the species.
Description
The skull of MNG 7722 is severely crushed dorsoventrally, making it hard to determine the shape of the skull in lateral view. It is 6.9 centimetres (2.7 in) in length, which is small for a trematopid. The orbitsOrbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...
, or eye sockets, are centrally placed so that the preorbital length of the skull is equal to that of the postorbital length. They make up around 30% of the skull length. The skull table seems to extend posteriorly past the level of the jaw articulation in Tambachia, which is unique among trematopids. However, this is likely to have been the result of crushing of the skull, which displaced the skull table.
Tambachia, like other trematopids, likely possessed a salt gland
Salt gland
The salt gland is an organ for excreting excess salts. It is found in elasmobranchs, seabirds, and some reptiles. In sharks, salt glands are found in the rectum, but in birds and reptiles, they are found in or on the skull, in the area of the eyes, nostrils or mouth. In crocodiles, the salt is...
similar to those seen in modern reptiles. The subdivision of the external naris
Nostril
A nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation...
into anterior and posterior portions is evidence of the presence of salt glands. The anterior portion is sub-circular and is thought to be the true narial opening. The posterior portion likely held the salt gland. The expansion of the posterior portion may not be an accommodation for the salt gland, but rather a means of coping with cranial stresses during feeding.
The postcranial skeleton is well known in Tambachia, given the completeness of the holotype specimen. The relatively short tail, preserved only as a faint impression in MNG 7722, is 8.5 centimetres (3.3 in) long. The limbs are short, with four digits on the manus
Manus (zoology)
The manus is the zoological term for the distal portion of the fore limb of an animal. In tetrapods, it is the part of the pentadactyl limb that includes the metacarpals and digits . During evolution, it has taken many forms and served a variety of functions...
, or hand, and five digits on the pes
Pes (zoology)
The pes is the zoological term for the distal portion of the hind limb of tetrapod animals. It is the part of the pentadactyl limb that includes the metatarsals and digits . During evolution, it has taken many forms and served a variety of functions...
, or foot. It is possible that the manus possessed five digits, since Acheloma
Acheloma
Acheloma is an extinct genus of temnospondyl that lived during the Early Permian. The type species is A. cumminsi. Trematops milleri has been synonymized with Acheloma. Like other trematopids, Acheloma was a large terrestrial carnivore. One species, A...
, another closely related trematopid, has been described as having five distal carpals. In the pes of the holotype specimen, there are only four digits preserved. However, since the third preserved digit is the longest, it likely represents the fourth digit, with the first digit absent due to imperfect preservation. The terminal phalanges of Tambachia were narrow, and would have been the core supports of claws.
Classification
In the original description of Tambachia, Sumida et al. (1998) concluded that AnconastesAnconastes
Anconastes is an extinct genus of dissorophoidean euskelian temnospondyl within the family Trematopidae. It is known from several fossils from the Late Carboniferous Cutler Formation of north-central New Mexico in the southwestern United States....
was the closest relative of Tambachia. Characteristics that supported this relationship included the absence of an internarial fenestra (which is also seen in dissorophids
Dissorophidae
Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the Late Pennsylvanian and early Permian periods in what is now North America and Europe...
, but was interpreted as a convergent
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
trait), the reduction of the suborbital process of the lacrimal
Lacrimal bone
The lacrimal bone, the smallest and most fragile bone of the face, is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders.-Lateral or orbital surface:...
, and a contribution to the ventral orbital rim (the rim of the eye socket) by the maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...
rather than the palatine
Palatine bone
The palatine bone is a bone in many species of the animal kingdom, commonly termed the palatum .-Human anatomy:...
. Below is a cladogram
Cladogram
A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...
modified from Sumida et al. (1998) showing the proposed relationships of Tambachia and other trematopids:
In their description of Fedexia
Fedexia
Fedexia is an extinct genus of carnivorous temnospondyl within the family Trematopidae. It lived 300 million years ago during the late Carboniferous period. It is estimated to have been two feet long, and likely resembled a salamander. Fedexia is known from a single skull found in Pittsburgh,...
, Berman et al. (2010) placed Fedexia as the sister taxon of the clade containing Tambachia and Anconastes. Tambachia, Anconastes, and Fedexia all possess a shallow and broadly concave occipital
Occipital bone
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoidal in shape and curved on itself...
margin. In other trematopids, the margin is biconcave. Below is a cladogram modified from Berman et al. (2010):
External links
- Tambachia in the Paleobiology DatabasePaleobiology Database' is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.-History:The Paleobiology Database was founded in 2000. It has been funded by the National Science Foundation and the Australian Research Council...