Musturzabalsuchus
Encyclopedia
Musturzabalsuchus is an extinct genus
of crocodylian, and one of the oldest known members of the superfamily Alligatoroidea
. The generic name means "Broadened rostrum crocodile", with "Musturzabal" meaning "broadened rostrum" in Basque
and "suchus" meaning "crocodile" in Latin
. The type
and only species
is M. buffetauti, named after the French paleoherpetologist Eric Buffetaut. The material first assigned to Musturzabalsuchus in 1997 has been found from the locality of Laño in Condado de Treviño
, northern Spain
. Although dating back to the Late Cretaceous
, the exact age of the strata in which material of Musturzabalsuchus occurs in the locality is not known: it is either Late Campanian
or very Early Maastrichtian
. Despite the unusually high quantity of remains belonging to the genus (most other continental Late Cretaceous crocodilian genera from Europe are poorly represented), the only skeletal elements known from Musturzabalsuchus are the maxilla
and mandible
. Some fragments of these bones have been found from the locality of Armuña in the province of Segovia
that were previously referred to an unnamed trematochampsid
. Like the holotype and paratype material found from Laño, these fossil
s, known collectively as UPUAM-502, are Campano-Maastrichtian in age. Another specimen (MHNM 10834.0) from the Fuvelian Lignites of France
has been referred to Musturzabalsuchus in 1999. However, the characteristics used to assign the material to better known specimens of Musturzabalsuchus from Spain were questioned in a later study. Material from Musturzabalsuchus has been found more recently from Valencia
, Spain, being slightly older in age than specimens from other localities, dating back to the Early or Middle Campanian.
that place it within Alligatoroidea, including a lateral displacement of the foramen aerum of the articular
. Additionally, the enlarged fourth mandibular tooth occludes into a pit in the rostrum. Only the latter feature is present in the more derived alligatorids
, and thus it is excluded from the family
. The pit that the fourth mandibular occludes into is placed posterior to the last premaxilla
ry tooth, similar to what is seen in "Diplocynodon" hantoniensis, another early alligatoroid. A figure used in an 1869 study by P. Matheron of crocodylian remains from the Fuveau lignites (illustration) pictured a mandible similar in profile to that of Musturzabalsuchus, but was labeled as belonging to the crocodylian Crocodilus affuvelensis. In 1997 it was suggested that due to this apparent similarity, along with the vagueness of descriptions in the 1869 paper and the loss of the syntype
, that C. affuvelensis could be reassigned to Musturzabalsuchus, although it was also acknowledged that the lack of posterior cranial material in the genus made detailed comparisons difficult. A recent 2008 study on Matheron's specimens colcuded that they belonged to a new genus distinct from Crocodylus
and different from Musturzabalsuchus, named Massaliasuchus
.
, a contemporary crocodilian also common from Laño, are thought to have been closely related to Paleolaurasian alligatoroids. The later genus is the only taxon not known from North America
to be related to the more derived Late Cretaceous tribodont alligatorids. It is clear that Musturzabalsuchus was endemic to Europe
, and was most likely restricted to Ibero-Armorica Island, as the genus is absent from Northern and Eastern European localities from which other alligatoroid fossils have been found.
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 crocodylian, and one of the oldest known members of the superfamily Alligatoroidea
Alligatoroidea
Alligatoroidea is a superfamily of crocodilians that evolved in the Late Cretaceous period. Cladistically, it is defined as Alligator mississippiensis and all crocodylians more closely related to A. mississippiensis than to either Crocodylus niloticus or Gavialis gangeticus ....
. The generic name means "Broadened rostrum crocodile", with "Musturzabal" meaning "broadened rostrum" in Basque
Basque language
Basque is the ancestral language of the Basque people, who inhabit the Basque Country, a region spanning an area in northeastern Spain and southwestern France. It is spoken by 25.7% of Basques in all territories...
and "suchus" meaning "crocodile" in Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
. The type
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
and only species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
is M. buffetauti, named after the French paleoherpetologist Eric Buffetaut. The material first assigned to Musturzabalsuchus in 1997 has been found from the locality of Laño in Condado de Treviño
Condado de Treviño
Condado de Treviño is a municipality in the province of Burgos, autonomous community of Castile and León, Spain. This municipality and the geographically smaller La Puebla de Arganzón make up the enclave of Treviño...
, northern Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
. Although dating back to the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
, the exact age of the strata in which material of Musturzabalsuchus occurs in the locality is not known: it is either Late Campanian
Campanian
The Campanian is, in the ICS' geologic timescale, the fifth of six ages of the Late Cretaceous epoch . The Campanian spans the time from 83.5 ± 0.7 Ma to 70.6 ± 0.6 Ma ...
or very Early Maastrichtian
Maastrichtian
The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...
. Despite the unusually high quantity of remains belonging to the genus (most other continental Late Cretaceous crocodilian genera from Europe are poorly represented), the only skeletal elements known from Musturzabalsuchus are 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...
and mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
. Some fragments of these bones have been found from the locality of Armuña in the province of Segovia
Segovia (province)
Segovia is a province of central/northern Spain, in the southern part of the autonomous community of Castile and León. It is bordered by the provinces of Burgos, Soria, Guadalajara, Madrid, Ávila, and Valladolid....
that were previously referred to an unnamed trematochampsid
Trematochampsidae
Trematochampsidae is an extinct family of mesoeucrocodylian crocodylomorph. Fossils are present from Madagascar, Morocco, Niger, Argentina, and Brazil...
. Like the holotype and paratype material found from Laño, these fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s, known collectively as UPUAM-502, are Campano-Maastrichtian in age. Another specimen (MHNM 10834.0) from the Fuvelian Lignites of France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
has been referred to Musturzabalsuchus in 1999. However, the characteristics used to assign the material to better known specimens of Musturzabalsuchus from Spain were questioned in a later study. Material from Musturzabalsuchus has been found more recently from Valencia
Valencian Community
The Valencian Community is an autonomous community of Spain located in central and south-eastern Iberian Peninsula. Its capital and largest city is Valencia...
, Spain, being slightly older in age than specimens from other localities, dating back to the Early or Middle Campanian.
Phylogenetics
Musturzabalsuchus possesses several synapomorphiesSynapomorphy
In cladistics, a synapomorphy or synapomorphic character is a trait that is shared by two or more taxa and their most recent common ancestor, whose ancestor in turn does not possess the trait. A synapomorphy is thus an apomorphy visible in multiple taxa, where the trait in question originates in...
that place it within Alligatoroidea, including a lateral displacement of the foramen aerum of the articular
Articular
The articular bone is part of the lower jaw of most tetrapods, including amphibians, sauropsids and early synapsids. In these animals it is connected to two other lower jaw bones, the suprangular and the angular...
. Additionally, the enlarged fourth mandibular tooth occludes into a pit in the rostrum. Only the latter feature is present in the more derived alligatorids
Alligatoridae
Alligatoridae is a family of crocodylians that includes alligators and caimans.- True alligators :Alligators proper occur in the fluvial deposits of the age of the Upper Chalk in Europe, where they did not die out until the Pliocene age. The true alligators are now restricted to two species, A...
, and thus it is excluded from 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...
. The pit that the fourth mandibular occludes into is placed posterior to the last premaxilla
Premaxilla
The incisive bone is the portion of the maxilla adjacent to the incisors. It is a pair of small cranial bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals....
ry tooth, similar to what is seen in "Diplocynodon" hantoniensis, another early alligatoroid. A figure used in an 1869 study by P. Matheron of crocodylian remains from the Fuveau lignites (illustration) pictured a mandible similar in profile to that of Musturzabalsuchus, but was labeled as belonging to the crocodylian Crocodilus affuvelensis. In 1997 it was suggested that due to this apparent similarity, along with the vagueness of descriptions in the 1869 paper and the loss of the syntype
Syntype
In biological nomenclature, a syntype is a term used to indicate a specimen with a special status.In zoological nomenclature, a syntype is defined as "Each specimen of a type series from which neither a holotype nor a lectotype has been designated [Arts. 72.1.2, 73.2, 74]. The syntypes...
, that C. affuvelensis could be reassigned to Musturzabalsuchus, although it was also acknowledged that the lack of posterior cranial material in the genus made detailed comparisons difficult. A recent 2008 study on Matheron's specimens colcuded that they belonged to a new genus distinct from Crocodylus
Crocodylus
Crocodylus is one of three genera from the Crocodylinae subfamily extending from the Crocodylidae family.Established species include three extinct species:* † Crocodylus acer - probably represents a distinct genus....
and different from Musturzabalsuchus, named Massaliasuchus
Massaliasuchus
Massaliasuchus is an extinct genus of crocodylian that is known from fossils found in Santonian-Campanian-age Upper Cretaceous rocks of southeastern France. Fossils belonging to this genus were published in 1869 by Matheron as Crocodilus affuvelensis. The new genus name was given to it in 2008 by...
.
Paleobiogeography
Musturzabalsuchus and AcynodonAcynodon
Acynodon is an extinct genus of alligatoroid crocodilian. When first described it was placed within the family Alligatoridae, but has since been reclassified as a globidontan. It is the oldest and most primitive globidontan known to date, with fossils being found from France, Spain, Italy, and...
, a contemporary crocodilian also common from Laño, are thought to have been closely related to Paleolaurasian alligatoroids. The later genus is the only taxon not known from North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
to be related to the more derived Late Cretaceous tribodont alligatorids. It is clear that Musturzabalsuchus was endemic to Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, and was most likely restricted to Ibero-Armorica Island, as the genus is absent from Northern and Eastern European localities from which other alligatoroid fossils have been found.
External links
- Musturzabalsuchus 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...