Post by Runic on Sept 9, 2013 22:04:40 GMT 5
Kaprosuchus
Kaprosuchus is an extinct genus of mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Greek kapros ("boar") and souchos ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar.[1] It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ZooKeys in 2009 along with other Saharan crocodyliformes such as Anatosuchus and Laganosuchus.[2] The type species is K. saharicus. Kaprosuchus is known from a nearly complete skull in which the lower jaw measured 603 mm long, whilst the entire animal is estimated to have been around 6 metres (20 feet) in length.[3] It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits into notches in upper jaw. This type of dentition is not seen in any other known crocodyliform. Another unique characteristic of Kaprosuchus is the presence of large, rugose horns formed from the squamosal and parietal bones that project posteriorly from the skull. Smaller projections are also seen in the closely related Mahajangasuchus.
The snout of Kaprosuchus shows generalized proportions and the naris is positioned dorsally. In Kaprosuchus many teeth are hypertrophied and labiolingually (laterally) compressed, unlike those of crocodyliforms with similarly shallow snouts, which are usually subconical and of moderate length. Another difference between the skull of Kaprosuchus and those of crocodyliforms that also possess dorsoventrally compressed snouts is the great depth of the posterior portion of the skull.
Restoration of the head
In Kaprosuchus, the orbits (i.e., eye sockets) open laterally and are angled slightly forward rather than upward. The orbits turned forward suggest that there was somewhat stereoscopic vision, i.e., an overlap in the visual field of the animal.[3]
The surfaces of the premaxillae are rugose with the edges elevated above the body of the bone, suggesting that a keratinous shield would have been supported by the rugosities at the tip of the snout. Along the interpremaxillary suture, the area where the two premaxillae meet, the surface is smooth, giving the paired rugosity of the premaxillae the resemblance of a moustache in anterior view.[1]
Siberian Tiger
The Siberian tiger (Panthera tigris altaica), also known as the Amur tiger, is a tiger subspecies inhabiting mainly the Sikhote Alin mountain region with a small subpopulation in southwest Primorye province in the Russian Far East. In 2005, there were 331–393 adult-subadult Amur tigers in this region, with a breeding adult population of about 250 individuals. The population has been stable for more than a decade due to intensive conservation efforts, but partial surveys conducted after 2005 indicate that the Russian tiger population is declining.[1]
The Siberian tiger is the largest living felid and ranks among the biggest felids to ever exist.[2]
Results of a phylogeographic study comparing mitochondrial DNA from Caspian tigers and living tiger subspecies indicate that the common ancestor of the Amur and Caspian subspecies colonized Central Asia from eastern China via the Gansu?Silk Road corridor from eastern China, and then subsequently traversed Siberia eastward to establish the Amur tiger population in the Russian Far East.[3]
The Siberian tiger is reddish-rusty or rusty-yellow in color, with narrow black transverse stripes. The body length is not less than 150 cm (60 in), condylobasal length of skull 250 mm (10 in), zygomatic width 180 mm (7 in), and length of upper carnassial tooth over 26 mm (1 in) long. It has an extended supple body standing on rather short legs with a fairly long tail.[4] It is typically 5–10 cm (2–4 in) taller than the Bengal tiger, which is about 107–110 cm (42–43 in) tall.[5]
Lying Siberian tiger
A Siberian tigress
Measurements taken by scientists of the Siberian Tiger Project in Sikhote-Alin range from 178 to 208 cm (70 to 82 in) in head and body length measured in straight line, with an average of 195 cm (77 in) for males; and for females ranging from 167 to 182 cm (66 to 72 in) with an average of 174 cm (69 in). The average tail measures 99 cm (39 in) in males and 91 cm (36 in) in females. The longest male "Maurice" measured 309 cm (122 in) in total length (tail of 101 cm (40 in)) and had a chest girth of 127 cm (50 in). The longest female "Maria Ivanna" measured 270 cm (110 in) in total length (tail of 88 cm (35 in)) and had a chest girth of 108 cm (43 in). These measurements show that the present Amur tiger is longer than the Bengal tiger and the African lion.[6] According to modern research of wild Siberian tigers in Sikhote-Alin, an average adult male of more than 35 months of age weighs 176.4 kg (389 lb), the average asymptotic limit being 222.3 kg (490 lb); an adult tigress weighs 117.9 kg (260 lb). The mean weight of historical Siberian tigers is supposed to be higher: 215.3 kg (475 lb) for male tigers and 137.5 kg (303 lb) for females.[7] In May 2011, a male called "Banzai" weighing 207 kg (460 lb) was radio-collared. This individual is heavier but smaller in size than a previously radio-collared male.[8]
Measurements of more than fifty captured individuals suggest that body size is similar to that of Bengal tigers.[9]
The largest male, with largely assured references, measured 350 cm (140 in) "over curves", equivalent to 330 cm (130 in) between pegs. The tail length in fully grown males is about 1 m (39 in). Weights of up to 318 kg (700 lb) have been recorded and exceptionally large males weighing up to 384 kg (850 lb) are mentioned in the literature but, according to Mazák, none of these cases can be confirmed via reliable sources.[10]
A further unconfirmed report tells of a male tiger shot in the Sikhote-Alin Mountains in 1950 weighing 384 kg (850 lb) with an estimated length of 3.48 m (11.4 ft). In some cases, Siberian tigers in captivity reached a body weight of up to 465 kg (1,030 lb), such as the tiger "Jaipur".[11]
Skull[edit source]
The skull of the Siberian tiger is characterized by its large size, and is similar to the skull of a lion, and differs in the structural features of the lower jaw and relative length of nasals. The facial region is very powerful and very broad in the region of the canines.[4] The skull prominences, especially sagittal crest and crista occipitalis are very high and strong in old males, and often much more massive than usually observed in the biggest skulls of Indian tigers. The size variation in skulls of Siberian tigers ranges from 331 to 383 mm (13.0 to 15.1 in) in 9 individuals measured. A female skull is always smaller and never so heavily built and robust as that of a male. The height of the sagittal crest in its middle-part reaches as much as 27 mm (1.1 in), and in its posterior part up to 46 mm (1.8 in).[12]
Female skulls range from 279.7 to 310.2 mm (11.01 to 12.21 in). The skull length of the males from Turkestan had a maximum length of 297.0 to 365.8 mm (11.69 to 14.40 in), while that of females measured 195.7 to 255.5 mm (7.70 to 10.06 in). In January 1954, a tiger killed on the Sumbar in Kopet-Dag had a skull greatest length of 385 mm (15.2 in), which is considerably more than the known maximum for this population and slightly exceeds that of most Far Eastern tigers. However, it's condylobasal length was of only 305 mm (12.0 in), smaller than those of the Amur tigers, with a maximum recorded condylobasal length of 342 mm (13.5 in).[6] The biggest skull of a Siberian tiger from Manchuria measured 406 mm (16.0 in) in length, which is about 20–30 mm (0.79–1.2 in) more than the maximum skull lengths achieved by tigers from the Amur region and northern India.[13]
Kaprosuchus is an extinct genus of mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Greek kapros ("boar") and souchos ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar.[1] It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ZooKeys in 2009 along with other Saharan crocodyliformes such as Anatosuchus and Laganosuchus.[2] The type species is K. saharicus. Kaprosuchus is known from a nearly complete skull in which the lower jaw measured 603 mm long, whilst the entire animal is estimated to have been around 6 metres (20 feet) in length.[3] It possesses three sets of tusk-like caniniform teeth that project above and below the skull, one of which in the lower jaw fits into notches in upper jaw. This type of dentition is not seen in any other known crocodyliform. Another unique characteristic of Kaprosuchus is the presence of large, rugose horns formed from the squamosal and parietal bones that project posteriorly from the skull. Smaller projections are also seen in the closely related Mahajangasuchus.
The snout of Kaprosuchus shows generalized proportions and the naris is positioned dorsally. In Kaprosuchus many teeth are hypertrophied and labiolingually (laterally) compressed, unlike those of crocodyliforms with similarly shallow snouts, which are usually subconical and of moderate length. Another difference between the skull of Kaprosuchus and those of crocodyliforms that also possess dorsoventrally compressed snouts is the great depth of the posterior portion of the skull.
Restoration of the head
In Kaprosuchus, the orbits (i.e., eye sockets) open laterally and are angled slightly forward rather than upward. The orbits turned forward suggest that there was somewhat stereoscopic vision, i.e., an overlap in the visual field of the animal.[3]
The surfaces of the premaxillae are rugose with the edges elevated above the body of the bone, suggesting that a keratinous shield would have been supported by the rugosities at the tip of the snout. Along the interpremaxillary suture, the area where the two premaxillae meet, the surface is smooth, giving the paired rugosity of the premaxillae the resemblance of a moustache in anterior view.[1]
Siberian Tiger
The Siberian tiger (Panthera tigris altaica), also known as the Amur tiger, is a tiger subspecies inhabiting mainly the Sikhote Alin mountain region with a small subpopulation in southwest Primorye province in the Russian Far East. In 2005, there were 331–393 adult-subadult Amur tigers in this region, with a breeding adult population of about 250 individuals. The population has been stable for more than a decade due to intensive conservation efforts, but partial surveys conducted after 2005 indicate that the Russian tiger population is declining.[1]
The Siberian tiger is the largest living felid and ranks among the biggest felids to ever exist.[2]
Results of a phylogeographic study comparing mitochondrial DNA from Caspian tigers and living tiger subspecies indicate that the common ancestor of the Amur and Caspian subspecies colonized Central Asia from eastern China via the Gansu?Silk Road corridor from eastern China, and then subsequently traversed Siberia eastward to establish the Amur tiger population in the Russian Far East.[3]
The Siberian tiger is reddish-rusty or rusty-yellow in color, with narrow black transverse stripes. The body length is not less than 150 cm (60 in), condylobasal length of skull 250 mm (10 in), zygomatic width 180 mm (7 in), and length of upper carnassial tooth over 26 mm (1 in) long. It has an extended supple body standing on rather short legs with a fairly long tail.[4] It is typically 5–10 cm (2–4 in) taller than the Bengal tiger, which is about 107–110 cm (42–43 in) tall.[5]
Lying Siberian tiger
A Siberian tigress
Measurements taken by scientists of the Siberian Tiger Project in Sikhote-Alin range from 178 to 208 cm (70 to 82 in) in head and body length measured in straight line, with an average of 195 cm (77 in) for males; and for females ranging from 167 to 182 cm (66 to 72 in) with an average of 174 cm (69 in). The average tail measures 99 cm (39 in) in males and 91 cm (36 in) in females. The longest male "Maurice" measured 309 cm (122 in) in total length (tail of 101 cm (40 in)) and had a chest girth of 127 cm (50 in). The longest female "Maria Ivanna" measured 270 cm (110 in) in total length (tail of 88 cm (35 in)) and had a chest girth of 108 cm (43 in). These measurements show that the present Amur tiger is longer than the Bengal tiger and the African lion.[6] According to modern research of wild Siberian tigers in Sikhote-Alin, an average adult male of more than 35 months of age weighs 176.4 kg (389 lb), the average asymptotic limit being 222.3 kg (490 lb); an adult tigress weighs 117.9 kg (260 lb). The mean weight of historical Siberian tigers is supposed to be higher: 215.3 kg (475 lb) for male tigers and 137.5 kg (303 lb) for females.[7] In May 2011, a male called "Banzai" weighing 207 kg (460 lb) was radio-collared. This individual is heavier but smaller in size than a previously radio-collared male.[8]
Measurements of more than fifty captured individuals suggest that body size is similar to that of Bengal tigers.[9]
The largest male, with largely assured references, measured 350 cm (140 in) "over curves", equivalent to 330 cm (130 in) between pegs. The tail length in fully grown males is about 1 m (39 in). Weights of up to 318 kg (700 lb) have been recorded and exceptionally large males weighing up to 384 kg (850 lb) are mentioned in the literature but, according to Mazák, none of these cases can be confirmed via reliable sources.[10]
A further unconfirmed report tells of a male tiger shot in the Sikhote-Alin Mountains in 1950 weighing 384 kg (850 lb) with an estimated length of 3.48 m (11.4 ft). In some cases, Siberian tigers in captivity reached a body weight of up to 465 kg (1,030 lb), such as the tiger "Jaipur".[11]
Skull[edit source]
The skull of the Siberian tiger is characterized by its large size, and is similar to the skull of a lion, and differs in the structural features of the lower jaw and relative length of nasals. The facial region is very powerful and very broad in the region of the canines.[4] The skull prominences, especially sagittal crest and crista occipitalis are very high and strong in old males, and often much more massive than usually observed in the biggest skulls of Indian tigers. The size variation in skulls of Siberian tigers ranges from 331 to 383 mm (13.0 to 15.1 in) in 9 individuals measured. A female skull is always smaller and never so heavily built and robust as that of a male. The height of the sagittal crest in its middle-part reaches as much as 27 mm (1.1 in), and in its posterior part up to 46 mm (1.8 in).[12]
Female skulls range from 279.7 to 310.2 mm (11.01 to 12.21 in). The skull length of the males from Turkestan had a maximum length of 297.0 to 365.8 mm (11.69 to 14.40 in), while that of females measured 195.7 to 255.5 mm (7.70 to 10.06 in). In January 1954, a tiger killed on the Sumbar in Kopet-Dag had a skull greatest length of 385 mm (15.2 in), which is considerably more than the known maximum for this population and slightly exceeds that of most Far Eastern tigers. However, it's condylobasal length was of only 305 mm (12.0 in), smaller than those of the Amur tigers, with a maximum recorded condylobasal length of 342 mm (13.5 in).[6] The biggest skull of a Siberian tiger from Manchuria measured 406 mm (16.0 in) in length, which is about 20–30 mm (0.79–1.2 in) more than the maximum skull lengths achieved by tigers from the Amur region and northern India.[13]
