Crocutoid hyaenas are a non-systematic group known from the Late Miocene to the Pleistocene, combining forms that show a trend toward cutting and bone-cracking dental morphology, typical of the extant genus Crocuta. Their key features include a tendency toward elongation of m1, reduction of its metaconid and talonid, and an increase in the size and robustness of p3. This group includes genera Adcrocuta, Pliocrocuta, and Pachycrocuta. All these taxa were widely distributed across Eurasia and Africa, while their stratigraphic ranges hardly overlapped, making crocutoid hyaenas useful for interregional and intercontinental faunal correlation, biostratigraphy, and paleogeography.
The crocutoid group is best known from Western Europe and East Asia (mainly China), whereas finds from central Eurasia remained poorly studied. New material from European Russia, southern Siberia, Ukraine, Tajikistan, Kyrgyzstan, and Mongolia fills this gap and allows reconstruction of crocutoid morphological evolution over approximately 9.5 million years.
Adcrocuta represents the earliest crocutoid hyaena, appearing in the Late Miocene. It coexisted with other hyaenids of hyper-carnivorous and omnivorous adaptations and exhibits early crocutoid traits, including robust dentition, reduction of the m1 metaconid, and a short, broad snout. Following the mass extinction of hyaenid members at the Miocene-Pliocene boundary, crocutoid forms became dominant.
It was established that in the studied regions, as elsewhere in Eurasia, Pliocrocuta replaced Adcrocuta. Our analysis confirms increasing crocutoid specialization in Pliocrocuta, expressed in the enlargement of cheek teeth, reduction of the premolar cingulum, and progressive loss of the m1 metaconid. For the first time, the recognition of stratigraphically significant chrono-species is morphologically substantiated.
The next stage of the crocutoid group is represented by Pachycrocuta. It is shown that in the studied region, Pachycrocuta exhibits advanced morphotypes, compared to the earlier Pachycrocuta, including restructuring of the m1 talonid and further reduction of the premolar cingulum.