Messelopython

Messelopython freyi was a small snake from the Middle Eocene Messel Pit in Germany, about 47.5 million years ago. Several articulated fossils preserve much more than isolated vertebrae, including skull material and long sections of the spine. Hussam Zaher and Krister Smith named the species in 2020 and recovered it on the stem of Pythonidae, outside the crown group of living pythons. Its fossils also show that a python-line snake lived in the same ecosystem as boa relatives, so modern geographic separation cannot simply be projected onto the Eocene past. The species appears in the ancient lizard and snake catalogue.

Quick facts

From Messel fossils to a named python

The species was described from several specimens collected in the Messel fossil site, a former volcanic maar lake near Darmstadt. The holotype SMNK-PAL 461 includes a nearly complete postcranial skeleton and parts of the skull. Other material, including specimens from museum collections in Frankfurt and Darmstadt, adds anatomical information and a broader size sample.

The name joins Messel, the locality, with Python, the family-lineage assignment. The epithet freyi honours German palaeontologist Eberhard Frey. The fossils are about 47.57 million years old based on the stratigraphic position and age constraints of the formation, rather than a direct measurement on the snake bones.

One of the most complete specimens is close to 97 centimetres long. That total is reconstructed from the preserved vertebral series and associated body remains. It is not a length measured from a fully articulated animal with every extremity and tail tip intact. The sample supports a relatively small snake, not the multi-metre size of many living pythons.

Why the analysis places it on the python stem

Zaher and Smith coded features from the skull and postcranial skeleton alongside living and fossil snakes. Their phylogenetic analysis placed Messelopython on the stem of Pythonidae: closer to living pythons than to other sampled snakes, but outside the group formed by their living common ancestor and descendants.

This placement makes the fossil an early record of the python lineage, but it does not mean modern python anatomy was already identical. Fossil branches can preserve a mosaic of features, and relationships may shift as new specimens or characters are added. The evidence is the character combination in the bones; the evolutionary tree is the analytical result built from those observations.

The classification also distinguishes Messelopython from the several booid snakes at the same site, including Messelophis and Eoconstrictor. Their temporal overlap is supported by the Messel collection. Direct encounters, shared prey or competition are not preserved.

Skull, teeth and body proportions

The preserved skull and jaws carry small recurved teeth. Zaher and Smith used cranial details together with vertebral characters to test its position among snakes. Tooth shape fits the general role of grasping prey, but no species-specific meal is reported from the fossils. The anatomy cannot identify one preferred prey species.

The vertebral column is unusually useful for estimating total length because a long, connected series is preserved. Counts and proportions provide a firmer basis than extrapolation from one vertebra, although missing sections and the tail tip still require reconstruction. Different specimens also vary in size, and the fossils do not establish whether all variation is due to growth, sex or individual differences.

No scale pattern or original colour is known. A lifelike restoration has to infer the soft body outline from living snakes and the preserved skeleton. Such a reconstruction can be anatomically plausible without being a direct record of pattern, posture or hunting behaviour.

A snake in the Messel forest

The Messel maar held a deep lake surrounded by warm, humid forest. Fine organic sediment and low-oxygen bottom waters helped preserve delicate skeletons. The site records fishes, amphibians, crocodilians, turtles, mammals and several snakes. A fossil deposited in the lake may have washed in from land, so burial setting is not equivalent to habitat preference.

Messelopython lived alongside small booids and larger snakes. Modern pythons and boas have largely separate natural ranges, but their Eocene fossil relatives shared this ecosystem. This challenges a simple claim that the two lineages could not coexist. It does not tell whether they ate the same prey, occupied the same microhabitat or interacted directly.

The secure picture is a small Eocene snake on the python stem, known from unusually informative fossils in Germany. Its exact diet, behaviour, colour and relationship to later python branches remain questions that a larger fossil sample could refine.