''Henkelotherium'' is an extinct genus of
dryolestida
Dryolestida is an extinct order of mammals, known from the Jurassic and Cretaceous. They are considered basal members of the clade Cladotheria, close to the ancestry of therian mammals. It is also believed that they developed a fully mammalian ...
n mammal from the Late Jurassic (
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 154.8 ±0.8 Ma and 149.2 ±0.7 Ma (million years ago). The Kimmeridgian follows the Oxfordian ...
)
Camadas de Guimarota, in Portugal. Unlike many other Jurassic mammals, it is known from a largely complete skeleton, and is thought to have had an
arboreal
Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...
lifestyle.
Description
The skull of ''Henkelotherium'' is long, and presacral body length is . This suggest a weight of about .
Paleobiology
Primitive characters of ''Henkelotherium'' (e.g. asymmetric condyles of the femur) indicate that this species had a mode of locomotion similar to
tree shrews
The treeshrews (also called tree shrews or banxrings) are small mammals native to the tropical forests of South and Southeast Asia. They make up the entire order Scandentia (from Latin ''scandere'', "to climb"), which split into two families: the ...
and
opossums
Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 126 species in 18 genera. Opossums originated in South America and entered North A ...
. The small size of ''Henkelotherium'' and elongated tail made it suited to an arboreal lifestyle and capable of climbing trees, a notion supported by the paleoecological reconstruction of the Guimarota ecosystem indicating a densely vegetated environment. Based on its late growth of jaws and it possessing additional molars that erupted after antemolar replacement was completed, ''Henkelotherium'' is believed to have had a long lifespan, a slower life history, or a combination of the two.
Taxonomy
In cladistic analyses, ''Henkelotherium'' has been considered closely related to
Dryolestidae
Dryolestidae is an extinct family of Mesozoic mammals, known from the Middle Jurassic to the Early Cretaceous of the North Hemisphere. The oldest known member, '' Anthracolestes'', is known from the Middle Jurassic Itat Formation of Western Siber ...
, either as a part of that group, or as closely related but placed outside that family as a non-dryolestid
dryolestida
Dryolestida is an extinct order of mammals, known from the Jurassic and Cretaceous. They are considered basal members of the clade Cladotheria, close to the ancestry of therian mammals. It is also believed that they developed a fully mammalian ...
n.
See also
*
Prehistoric mammal
This is an incomplete list of prehistoric mammals. It does not include extant mammals or recently extinct mammals. For extinct primate species, see: list of fossil primates.Mikko's Phylogeny Archiv
Mammaliaformes
'
*Genus †''Adelobasile ...
**
List of prehistoric mammals
This is an incomplete list of prehistoric mammals. It does not include List of mammals, extant mammals or List of extinct mammals, recently extinct mammals. For extinct primate species, see: list of fossil primates.Mikko's Phylogeny Archiv
Ma ...
References
Further reading
* Ramón Vázquez Molinero: Comparative anatomy of Henkelotherium guimarotae (Holotheria), a late Jurassic small mammal, and its relevance for the evolution of the mode of locomotion of modern mammals. Dissertation. Freie Universität Berlin, Fachbereich Geowissenschaften, 2003. Dissertation Online
http://www.diss.fu-berlin.de/diss/receive/FUDISS_thesis_000000001206
Dryolestida
Late Jurassic mammals of Europe
Jurassic Portugal
Fossils of Portugal
Fossil taxa described in 1991
Prehistoric mammal genera
{{jurassic-mammal-stub