Archaeohyrax patagonicus

Overview

Archaeohyrax patagonicus is an extinct mammal from Late Oligocene South America. A type specimen with the skull and lower jaw articulated is important research material. Comparing the head and teeth together reveals differences among ancient mammals.^[1]

Key facts

When the skull and lower jaw remain together, upper and lower teeth can be compared side by side. Type specimen MACN A52-617 shows this connection. It is better suited than isolated teeth alone to examining the relationships among the positions of parts within the head.^[1]

Time and place

It is studied from material of the Deseadan interval of the Late Oligocene in South America. The type locality has been presumed to be Cabeza Blanca in present-day Argentina. The Oligocene was roughly 34–23 million years ago.^[1][3]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The type specimen consists of a skull with an articulated lower jaw. A summary introducing this specimen describes a tall, blunt snout and high tooth crowns. Snout height and tooth form are features to note when comparing heads.^[1][2]

The upper tooth row of Archaeohyrax patagonicus in the literature measures 84mm from the first incisor to the third molar. Teeth extending about 8.4cm from incisors to molars evoke the form of a food-processing jaw.^[4]

Habitat and reproduction

High tooth crowns and jaw construction allow comparisons of feeding apparatuses. Researchers examined the heads and teeth of archaeohyracids across several species. Detailed study of one body region reveals varied forms even among related groups.^[1][2]

Fossil discovery

MACN A52-617 was studied as the type specimen defining this species’ name. A 2009 study reconsidered heads and teeth while comparing Late Oligocene archaeohyracids from Bolivia and Argentina. An old specimen thus participated in new comparisons and phylogenetic questions.^[1]

References

1. Billet et al. (2009) — Skulls and teeth of South American archaeohyracids
2. Archaeohyrax — Head and teeth of the type specimen
3. International Commission on Stratigraphy (2024) — Geological time chart
4. Loomis (1914), The Deseado Formation of Patagonia
5. Revised diagnosis of the head and teeth of Scarrittia
6. 2012 study — Body and limb comparisons of leontiniids

Research questions

How closely related are animals with similar heads and teeth? A 2009 study compared several cranial and dental features and proposed new phylogenetic hypotheses. Research begins with finding visible similarities and continues by asking about relationships.^[1]

Observation

Move your gaze from the tall, blunt snout to the lower jaw and molars. Imagining where the upper and lower jaws connect helps explain the comparisons for which one type specimen can be used.^[1][2]