Early history The
holotype of
Pelorovis, consisting of a skull (Pel 1) and multiple horn cores and skull pieces (Pel 1–Pel 23), was found in
Olduvai Gorge, in northern
German East Africa (now
Tanzania), by geologist
Hans Reck. The expedition in question was the first time the locality was explored by a palaeontologist. Initially, Reck believed that he had uncovered the remains of a large member of the subfamily
Caprinae, which includes modern goats and sheep. Specifically, he believed that the fossils he had uncovered represented a close relative of the latter, though one that was quite geographically isolated. The fossils were kept in Berlin, and in 1928, Reck described a new genus and species,
Pelorovis oldowayensis, to accommodate them. The binomial name chosen by Reck is compounded from the
Greek πέλωρος (
péloros) in the sense of "monstrous" or "huge and terrible" and
Latin ovis, meaning "sheep". In 1991, John Michael Harris described remains uncovered as part of the Koobi Fora research project in northern Kenya. Distinguishing it from
Pelorovis oldowayensis based on its smaller and more upwardly curved horns, he named it
P. turkanensis. In 2004, Denis Geraads, Véra Eisenmann and Germaine Petter further divided
P. turkanensis into two
subspecies:
P. turkanensis brachyceras, and
P. turkanensis turkanensis, the former distinguished from the latter by having horn cores with a thick base that quickly taper along their length. In 2005, Djillali Hadjouis and Mohamed Sahnouni described a third
Pelorovis species based on a partial skull recovered from the
Aïn Hanech Formation of Algeria. The specimen preserved the upper part of the
frontals and
parietals, as well as both
horn cores. The new taxon was named
Pelorovis howelli, after palaeontologist Clark Howell. It differed from the other two species in having smaller horn cores that were set farther apart. In 1979,
Camille Arambourg named
Bos bubaloides and
B. praeafricanus, both from Aïn Hanech. In 1998, Denis Geraads & Fethi Amani re-examined the remains and tentatively reassigned them to
Pelorovis. Thus,
P. praeafricanus is occasionally regarded as a species of
Pelorovis. However, the
syntype of
P. praeafricanus, a
metacarpal, closely resembles that of
P. oldowayensis, and it may represent the same taxon.
Possible synonymy with Bos A 2007 study by Bienvenido Martínez-Navarro and colleagues of the
morphology of the fossil remains came to the conclusion that
Pelorovis is probably not
monophyletic. These authors reclassify the early forms of the genus,
P. turkanensis and
P. oldowayensis, in the genus
Bos. In contrast, they find that the late Pleistocene form
Pelorovis antiquus seems to be a close relative of the modern
African buffalo (
Syncerus caffer). This approach essentially subsumes the genus as a synonym of
Bos, because the type species is
P. oldowayensis. A number of the authors of this study reiterated their classification of the taxa
Pelorovis turkanensis and
P. oldowayensis in the genus
Bos in another paper published 2014. Alexandre Hassanin, in 2014, followed the interpretations of Martínez-Navarro
et al., pointing to previous genetics work which show that the bovid lineages which produced the modern species within the genera
Bos,
Bubalus and
Syncerus split from each other some eight to nine million years ago, indicating that either the fossil ancestors of these species have not yet been discovered, or that they already have been found, but are taxonomically misidentified. Hassanin further pointed out that Martínez-Navarro
et al. were only looking for the ancestor of
Bos primigenius in their studies of African fossil bovids, and that the Asian species of
Bos may have been derived from other fossil species. Lastly, Hassanin notes that if
Pelorovis is reduced into synonymy due to these studies, this also implies the other Pleistocene fossil genera
Leptobos and
Epileptobos are synonymous with
Bos. A 2018 study by Tong
et al. of the Chinese fossil representation of
Bos primigenius uses morphology to dispute these conclusions regarding these taxa belonging to the genus
Bos, as well as if they are the ancestral line from which
Bos evolved, instead hewing to the traditional interpretation that the Indian Early Pleistocene fossil species
Bos acutifrons is the primordial ancestor of
Bos.
Reassigned species The long-horned buffalo,
Syncerus antiquus, was described by
Georges Louis Duvernoy in 1851 from a skull discovered along the
Bou Sellam River near the city of
Sétif,
Algeria. It was found at one meter in depth, when excavating the foundations of a new mill, and subsequently sent to Paris. Duvernoy believed this species to be closely related to the
Asian water buffalo (Bubalus bubalis) and classified it as
Bubalus antiquus. Several other fossils of
S. antiquus were described under the names
Bubalus bainii and
Bubalus nilssoni. In 1949,
Dorothy Bate recognized that these buffaloes were conspecific and not related to
Bubalus. She placed these fossils in a new genus,
Homoioceras. However, the type species of
Homoiceros was found to be synonymous with the
Cape buffalo, invalidating the genus. It was subsequently moved to
Pelorovis in 1978. However, a link with the living Cape buffalo has been noted based on morphological and systematic grounds, and since 1994 it has been suggested that
P. antiquus be moved into
Syncerus. This proposal has since gained widespread acceptance. Another former
Pelorovis species is "P"
. kaisensis, named in 1994 based on remains from
Kaiso, Uganda. Hadjouis and Sahnouni considered it to be closer to
Syncerus in 2005. ==Description==