Wang et al. 2026 "A giant Jurassic hunter: the earliest dipluran and its implications for hexapod body pattern evolution" (open access)
In summary:
- A formal description of Sinojapyx giganteus (family Sinojapygidae): new family, genus and species of dipluran (a group of non-insect hexapods), discovered from Middle Jurassic Daohugou Biota (c.a. 165 Mya), northeastern China. This also means it is the oldest unambiguous fossil record of dipluran so far.
- The body length of Sinojapyx measured above 5 cm, which is exceptionally large for a dipluran (usually below 2 cm).
- Phylogeny resolves Sinojapyx as a stem member of Japygoidea, a superfamily of diplurans with specialized pincer-like cerci used for hunting (very similar to those of an earwig).
- It also featuring ectognathus (exposed) mouthparts, particularly a set of well-developed mandibles, in contrast to other extant non-insect hexapods which characterized by entognathus (hidden) mouthparts.
- The giant size, robust mouthparts and cerci suggest Sinojapyx is a top predator of the topsoil environment, perhaps occupying an ecological role similar to scorpions and centipedes.
- The mouthparts strengthen the idea that ectognathy (as seen in Sinojapyx and insects) is the ancestral condition of hexapod arthropods, with entoghathy evolved independently (convergent) within all 3 groups of non-insect hexapods: diplurans, springtails and proturans.
u/DifficultDiet4900 — 8 days ago