Marine Reptile Month #15 — Helveticosaurus

Middle Triassic period (~245-230 mya)

Helveticosaurus was one of the more unusual Triassic marine reptiles. 2m long (6ft 6in) and shaped a little like a cross between a marine iguana and a penguin, it had both a long flexible tail for propulsion as well as large flipper-like forelimbs — suggesting it swam using a strange combination of undulation and paddling. Its skull was also rather weird, with long fang-like teeth lining its jaws, and with its head being very short and boxy compared to the more streamlined shapes of most other marine reptiles. It’s not clear what it was feeding on with such an unusual skull, aside from the teeth suggesting it was some sort of predator.

Its evolutionary relationships are still completely unknown, too, with the current best guess being that it might have been a relative of the basal archosauromorphs.

Color palette used: “Smooth Sailing

Helveticosaurus and Ticinosuchus, Doug Henderson

Waves and wind beat salt and stone—ingredients for mountains—masses of rock that will be thrust high enough to collect glaciers on their peaks. But now, there are no alpine summits. Instead, stony islands lie low, battered by waves from the Tethys, their barren surfaces crawling with reptiles. Helveticosaurs, blunt-faced, nasty-fanged, drag their hulks across the raw rocks and snort salt from their noses. When their beds are driven skyward by colliding continents, the only water those stones will know will be ice.