I thought some people using iNat data are in this discussion https://forum.inaturalist.org/t/species-accumulation-curves-for-inat-data/38222/30
https://forum.inaturalist.org/t/species-accumulation-curves-for-inat-data/38222/29
https://onlinelibrary.wiley.com/share/ZHQTBHHSYHITEZZNYMGV?target=10.1111/j.1654-1103.2010.01247.x
https://bsapubs.onlinelibrary.wiley.com/share/YMDXUWKTUG5C5D8JMVFA?target=10.3732/ajb.1000215