''Borealestes'' is a genus of docodontan from the

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

of Britain, first discovered on the

Isle of Skye The Isle of Skye, or simply Skye, is the largest and northernmost of the major islands in the Inner Hebrides of Scotland. The island's peninsulas radiate from a mountainous hub dominated by the Cuillin, the rocky slopes of which provide some of ...

near the village of Elgol. It was the earliest mammaliaform from the

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

found and named in Scotland. A second species and was later found in other Middle Jurassic sites in England, but is now shown to be a different genus. A new species, ''B. cuillinensis'' was named in 2021, also from Skye.

Etymology

The genus name is derived from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

Boreas and

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

Boreal, meaning ''northern'', the

listís meaning ''brigand'' or ''rogue''. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

of ''B. serendipitus'' comes from the noun ''serendipity'', relating to making a happy and unexpected discovery by accident. The species name ''B. cuillinensis'' comes from the

Cuillin The Cuillin () is a range of mostly jagged rocky mountains on the Isle of Skye in Scotland. The main Cuillin ridge is also called the Black Cuillin to distinguish it from the Red Cuillin ('), which lie to the east of Glen Sligachan.R. Anderson & ...

mountains on Skye, which are near the discovery site, and the cusps of the teeth resemble the peaks of the mountains.

Discovery

The first fossil of ''Borealestes serendipitus'' was discovered by Michael Waldman during a school field trip he was leading on the Isle of Skye in 1971. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

is a fragment of jaw containing five molars and three premolars (BRSUG 20572)Panciroli, E., Benson, R.B. and Luo, Z.X., 2019
The mandible and dentition of Borealestes serendipitus (Docodonta) from the Middle Jurassic of Skye, Scotland
Journal of Vertebrate Paleontology, 39(3), p.e1621884 and there were several other jaw fragments collected in the following years, and a partial skeleton, all of them from the Kilmaluag Formation. Michael Waldman and Robert J. G. Savage then carried out multiple trips to the island in search of mammals and other fossils. They named ''Borealestes'' at the same time as a new species of

tritylodontid Tritylodontidae ("three-knob teeth", named after the shape of their cheek teeth) is an extinct family of small to medium-sized, highly specialized mammal-like cynodonts, with several mammalian traits including erect limbs, endothermy, and some d ...

, '' Stereognathus 'hebridicus' '' (now synonymised with ''S. ooliticus''). In 2003, ''Borealestes mussettae'' (originally 'B. mussetti') was named from isolated molars found in the

Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...

aged

Kirtlington Kirtlington is a village and Civil parishes in England, civil parish in Oxfordshire about west of Bicester. The parish includes the Hamlet (place), hamlet of Northbrook. The United Kingdom Census 2011, 2011 Census recorded the parish's popula ...

Mammal bed of

Oxfordshire Oxfordshire ( ; abbreviated ''Oxon'') is a ceremonial county in South East England. The county is bordered by Northamptonshire and Warwickshire to the north, Buckinghamshire to the east, Berkshire to the south, and Wiltshire and Glouceste ...

, England.Sigogneau-Russell D. 200
Docodonts from the British Mesozoic
Acta Palaeontologica Polonica 48, 3, 357-374 Both of these localities belong to the

Forest Marble Formation The Forest Marble is a geological formation in England. Part of the Great Oolite Group, it dates to the late Bathonian stage of the Middle Jurassic.Weishampel, David B; et al. (2004). "Dinosaur distribution (Middle Jurassic, Europe)." In: Weisha ...

. It was named ''mussetti'' in honour of Frances Mussett, in recognition of her major participation in fossil excavation at Kirtlington Cement Quarry. However, ''mussetti'' is the masculine form, and so this has been amended to ''mussettae'' by subsequent authors. It was recently recognised as different from ''Borealestes'', and so moved to the newly erected genus '' Dobunnodon'' in 2021. A new species, ''B. cuillinensis'', was named in 2021 based on a partial skeleton found in the same site in the Kilmaluag Formation,

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

. It was found in 2018 by Prof Richard Butler of the University of Birmingham, during fieldwork on the island.

Appearance

''Borealestes'' is currently known from two partial skeletons which include skull bones, jaws, and postcrania, multiple isolated teeth, and ear bones ( petrosalsPanciroli, E., Schultz J.A., and Luo, Z-X. 2018
The morphology of the petrosal and stapes of Borealestes (Mammaliaformes, Docodonta) from the Middle Jurassic of Skye, Scotland
Papers in Palaeontology https://doi.org/10.1002/spp2.1233).

Docodonta Docodonta is an Order (biology), order of extinct Mesozoic Mammaliaformes, mammaliaforms (advanced cynodonts closely related to true Crown group, crown-group mammals). They were among the most common mammaliaforms of their time, persisting from t ...

ns are small (shrew to rat sized) mammaliaforms - the wider grouping that includes mammalians and their closest relatives. ''Borealestes'' is believed to be a basal member of

.Luo Z-X, and Martin. 200
Analysis of molar structure and phylogeny of docodont genera
Bulletin of Carnegie Museum of Natural History 39: 27-47

References

{{Taxonbar, from=Q12899042 Docodonta Fossil taxa described in 1972 Taxa named by Michael Waldman (paleontologist) Taxa named by R. J. G. Savage Middle Jurassic synapsids of Europe