|Fourth-instar rhopalosomatid larva of unknown genus (Lohrmann & Engel, 2017)|
The amber inclusion of an unmistakable fourth-instar rhopalosomatid larva, described in situ behind a cricket's hind leg (Gryllidae; it cannot be identified beyond familial level), is a "confluence of rarities" (Lohrmann & Engel, 2017). Rhopalosomatids are rare in the fossil record, with only four fossil species having been described; of these, only Eorhopalosoma gorgyra from Burmese amber can be confidently assigned to the family (Engel, 2008). (The other three are compression fossils.) Additionally, hosts of the order to which rhopalosomatids' cricket hosts belong (the Orthoptera) are only rarely preserved in amber (Heads, 2009).
|View of rhopalosomatid larva's left side and cricket's underside (Lorhmann & Engel, 2017)|
Regardless of the specimen's generic identity, it is remarkable that rhopalosomatids' niche, and concomitant morphology, has seemingly changed so little in 98 million years.
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