[D] Vulcanodon karibaensis [sG] [T]
Describer
Raath, 1972 > Cooper, 1984
Time
Jurassic Early ?Hettangian
Classification
Saurischia Sauropodomorpha Sauropoda Vulcanodontidae
Diet
Herbivore
Fossilsite
Vulcanodon Beds, Mashonaland, North, Zimbabwe
Length
6.5 meter
Info
Genus - Typespecies
The earliest and most primitive sauropod, from the Triassic-Jurassic boundary of Zimbabwe, is known from the pelvis, hindlimb and foot, forearm, proximal section of the tail.
Discovered in 1969 by Mr. B.A. Gibson of Kariba, Zimbabwe on an unnamed island “Island 126/127” in Lake Kariba. Locality of the fossil”16o 48’ 30” S; 28o 16’ 30” E. The large Saurischian specimen consisted out of the articulated pelvis, sacrum, tail and hind leg together with several other bones including parts of the forelimbs, and some teeth, registered as QG24 in the collection of the Queen Victoria Museum Salisbury, Zimbabwe.
The specimen lay near the top of a gritty, current-bedded sandstone layer, about 30 meter thick overlying the basal lave flow. Overlying the sandstone is the succeeding lave flow which is characterized by a large feldspar phenocrysts and, at the base, pillow structures which were recorded by Bond et al., 1970.
The material consist of the following elements; Eroded pelvis, showing parts of three sacral vertebrae, the base of the right ilium, and the pubis and ischium of both sides, more ore les complete; parts of both femora; the left tibia and fibula; tarsus, and most of the left pes; 12 anterior caudal vertebrae; the right radius and ulna; some metacarpals and phalanges of the fore foot; seven teeth; and some indeterminate fragments.
Diagnosis
Large quadrupedal saurischian, comparable in size and general proportions to the Sauropoda. In several respects morphologically intermediate between Prosauropoda and Sauropoda, but evidently belonging with the Prosauropoda as a late advanced representative. Retaining several primitive skeletal features: generalised “carnivorous” teeth: pubis and ischium of prosauropod type, pubis forming transverse distal apron: ilium incompletely known but probably of prosauropod type with short anterior process. Incorporating many advanced features which parallel developments in the Sauropoda: robust and solid structure of all limb bones: femur (incomplete) with four trochanter apparently precisely at midshaft; only proximal tarsals ossified; forearm very long, ulna being 106% of tibia length; sacrum probably of more than three sacral vertebrae (?4), Pes with all metatarsals well developed. Digit I of pes armed with large, sharp claw; digits II and III terminating in flattened “naillike” claws.
Etymology
The species name is in reference to the place of its discovery, Lake Kariba, and the generic name Vulcanodon is derived from the fact that this animal, with “good carnosaur teeth” was preserved sandwiched between two lave flows indicative of volcanism.
Sacrum and Pelvis
The sacrum in not well preserved, and several critical features are missing. Parts of three fully co-ossified sacrals are present, the first in the series lacking approximately the front of its centrum and all of its neural arch, transverse processes and ribs. The centra of the second and third preserved sacrals are more or less complete. The most striking feature of the sacrum in ventral view is the extraordinarily flat nature of the lower surface.
There is scarcely any topographical relief between the lower side of the sacral ribs (if such they are) and the centrum of the second sacral. The co-ossified ends of the centra are visible as low transverse “nodes”. The mid portions of the centra are much constricted, so that each centrum is waisted. The hind end of the last sacral is abruptly flared into a wide trumpet-shaped, sub-circular articulatory face, the circumference of which is a sharp ridge.
The articular surface is platycoelus. There is no identification of a saggital ventral groove of any of the sacrals. The sacral ribs, of which the second and third (as preserved) of both sides are present but eroded, are relatively broad and exceptionally thin lateral plates. They coalesce distally near the sacroiliac suture, enclosing an oblique elliptical intercostals space. The intercostals space between the first and second sacrals would appear also to have been an oblique ellipse, the long axes of the two adjacent ellipses converging laterally.
The dorsal parts of the sacrum are too badly eroded to permit any meaningful analysis. From what remains of these structures it would appear that the basis of the neural arches are present as there is a slight indication of a saggital furrow which probably represent the neural canal.
The true number of sacrals cannot be determined with accuracy. The “typical prosauropod” sacrum consists of three which may or may not be fully co-ossified (von Huene, 1932). On the other hand the “typical sauropod” sacrum consists of five (occasionally four or six) generally all of which are co-ossified. The nature of the sacrum centra in Vulcanodon suggests that there may have been more than the three which are preserved. The very flat nature of the first preserved centrum suggests that it was not the first in the series. Judging from the lengths of the succeeding two centra, approximately half of the first is missing.
The indication that at least one other sacral lay ahead of the first preserved, giving at least four sacrals, lends strength to the suggestion that the sacrum of Vulcanodon was more “sauropod” than “prosauropod” in appearance. The sacrum is a broad structure. If indeed it consisted of four sacrals, and assuming that the first sacral had a centrum length of approximately 1400 mm. the overall dimensions would have been approximately: length along the centra ca. 550 mm. maximum width ca. 400 mm.
Ilium
Only the base of the right ilium is preserved, including; the acetabular arch, a very small part of the base of the anterior process and a small part of the base of the posterior process, together with a very small strip of the iliac blade On the right hand side the sacrum and ilium are articulated along the sacroiliac suture. The lack of details of the ilium is very tantalising, because if it were complete it would help a great deal in unravelling the systematic position of this animal. What is preserved does not assist greatly in resolving this question.
Ischium
The ischium is a slender rod-like bone with an expanded distal end, and it is triangular in cross-section over most of its length. The two ischia meet distally in a comparatively short V-shaped symphysis. The glenoid surface of the acetabulum on the ischium has an upstanding medial rim, which shallows forwards onto the pubic quadrant of the acetabulum. The most remarkable characteristic of the ischium is its extreme length, considerably longer than the pubis.
Caudal vertebrae and chevrons
The tail is preserved, at least in part, from the first to the twelfth caudals. The first caudal is represented only by a small fragment of the hind part of its centrum articulated with the second caudal. The root of the tail seems to have been arthritic, in that the intercentral base of the first chevron (lying between caudals 3 and 4) is grossly enlarged and has grown up round the sides of these two vertebrae to ankylose then firmly together. The disease condition has also affected the vertebrae themselves as they are noticeably larger than the preceeding and succeeding caudals. Disregarding this abnormality, the caudal centra in this series of eleven more or less well preserved vertebrae are all of a comparable shape and size.
Raath, 1972
Raath, 1972 > Cooper, 1984
Time
Jurassic Early ?Hettangian
Classification
Saurischia Sauropodomorpha Sauropoda Vulcanodontidae
Diet
Herbivore
Fossilsite
Vulcanodon Beds, Mashonaland, North, Zimbabwe
Length
6.5 meter
Info
Genus - Typespecies
The earliest and most primitive sauropod, from the Triassic-Jurassic boundary of Zimbabwe, is known from the pelvis, hindlimb and foot, forearm, proximal section of the tail.
Discovered in 1969 by Mr. B.A. Gibson of Kariba, Zimbabwe on an unnamed island “Island 126/127” in Lake Kariba. Locality of the fossil”16o 48’ 30” S; 28o 16’ 30” E. The large Saurischian specimen consisted out of the articulated pelvis, sacrum, tail and hind leg together with several other bones including parts of the forelimbs, and some teeth, registered as QG24 in the collection of the Queen Victoria Museum Salisbury, Zimbabwe.
The specimen lay near the top of a gritty, current-bedded sandstone layer, about 30 meter thick overlying the basal lave flow. Overlying the sandstone is the succeeding lave flow which is characterized by a large feldspar phenocrysts and, at the base, pillow structures which were recorded by Bond et al., 1970.
The material consist of the following elements; Eroded pelvis, showing parts of three sacral vertebrae, the base of the right ilium, and the pubis and ischium of both sides, more ore les complete; parts of both femora; the left tibia and fibula; tarsus, and most of the left pes; 12 anterior caudal vertebrae; the right radius and ulna; some metacarpals and phalanges of the fore foot; seven teeth; and some indeterminate fragments.
Diagnosis
Large quadrupedal saurischian, comparable in size and general proportions to the Sauropoda. In several respects morphologically intermediate between Prosauropoda and Sauropoda, but evidently belonging with the Prosauropoda as a late advanced representative. Retaining several primitive skeletal features: generalised “carnivorous” teeth: pubis and ischium of prosauropod type, pubis forming transverse distal apron: ilium incompletely known but probably of prosauropod type with short anterior process. Incorporating many advanced features which parallel developments in the Sauropoda: robust and solid structure of all limb bones: femur (incomplete) with four trochanter apparently precisely at midshaft; only proximal tarsals ossified; forearm very long, ulna being 106% of tibia length; sacrum probably of more than three sacral vertebrae (?4), Pes with all metatarsals well developed. Digit I of pes armed with large, sharp claw; digits II and III terminating in flattened “naillike” claws.
Etymology
The species name is in reference to the place of its discovery, Lake Kariba, and the generic name Vulcanodon is derived from the fact that this animal, with “good carnosaur teeth” was preserved sandwiched between two lave flows indicative of volcanism.
Sacrum and Pelvis
The sacrum in not well preserved, and several critical features are missing. Parts of three fully co-ossified sacrals are present, the first in the series lacking approximately the front of its centrum and all of its neural arch, transverse processes and ribs. The centra of the second and third preserved sacrals are more or less complete. The most striking feature of the sacrum in ventral view is the extraordinarily flat nature of the lower surface.
There is scarcely any topographical relief between the lower side of the sacral ribs (if such they are) and the centrum of the second sacral. The co-ossified ends of the centra are visible as low transverse “nodes”. The mid portions of the centra are much constricted, so that each centrum is waisted. The hind end of the last sacral is abruptly flared into a wide trumpet-shaped, sub-circular articulatory face, the circumference of which is a sharp ridge.
The articular surface is platycoelus. There is no identification of a saggital ventral groove of any of the sacrals. The sacral ribs, of which the second and third (as preserved) of both sides are present but eroded, are relatively broad and exceptionally thin lateral plates. They coalesce distally near the sacroiliac suture, enclosing an oblique elliptical intercostals space. The intercostals space between the first and second sacrals would appear also to have been an oblique ellipse, the long axes of the two adjacent ellipses converging laterally.
The dorsal parts of the sacrum are too badly eroded to permit any meaningful analysis. From what remains of these structures it would appear that the basis of the neural arches are present as there is a slight indication of a saggital furrow which probably represent the neural canal.
The true number of sacrals cannot be determined with accuracy. The “typical prosauropod” sacrum consists of three which may or may not be fully co-ossified (von Huene, 1932). On the other hand the “typical sauropod” sacrum consists of five (occasionally four or six) generally all of which are co-ossified. The nature of the sacrum centra in Vulcanodon suggests that there may have been more than the three which are preserved. The very flat nature of the first preserved centrum suggests that it was not the first in the series. Judging from the lengths of the succeeding two centra, approximately half of the first is missing.
The indication that at least one other sacral lay ahead of the first preserved, giving at least four sacrals, lends strength to the suggestion that the sacrum of Vulcanodon was more “sauropod” than “prosauropod” in appearance. The sacrum is a broad structure. If indeed it consisted of four sacrals, and assuming that the first sacral had a centrum length of approximately 1400 mm. the overall dimensions would have been approximately: length along the centra ca. 550 mm. maximum width ca. 400 mm.
Ilium
Only the base of the right ilium is preserved, including; the acetabular arch, a very small part of the base of the anterior process and a small part of the base of the posterior process, together with a very small strip of the iliac blade On the right hand side the sacrum and ilium are articulated along the sacroiliac suture. The lack of details of the ilium is very tantalising, because if it were complete it would help a great deal in unravelling the systematic position of this animal. What is preserved does not assist greatly in resolving this question.
Ischium
The ischium is a slender rod-like bone with an expanded distal end, and it is triangular in cross-section over most of its length. The two ischia meet distally in a comparatively short V-shaped symphysis. The glenoid surface of the acetabulum on the ischium has an upstanding medial rim, which shallows forwards onto the pubic quadrant of the acetabulum. The most remarkable characteristic of the ischium is its extreme length, considerably longer than the pubis.
Caudal vertebrae and chevrons
The tail is preserved, at least in part, from the first to the twelfth caudals. The first caudal is represented only by a small fragment of the hind part of its centrum articulated with the second caudal. The root of the tail seems to have been arthritic, in that the intercentral base of the first chevron (lying between caudals 3 and 4) is grossly enlarged and has grown up round the sides of these two vertebrae to ankylose then firmly together. The disease condition has also affected the vertebrae themselves as they are noticeably larger than the preceeding and succeeding caudals. Disregarding this abnormality, the caudal centra in this series of eleven more or less well preserved vertebrae are all of a comparable shape and size.
Raath, 1972