Paropsonema

Paropsonema is an eldonioid known from the Devonian of upstate New York and (if P. mirabile is a species of Paropsonema rather than Discophyllum) the Silurian of southern Australia. It is the latest-surviving known member of the Eldonioidea and Cambroernida.^[1]

Paropsonema Temporal range: Devonian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Stem group:	Ambulacraria
Clade:	†Cambroernida
Class:	†Eldonioidea
Clade:	†Paropsonemida
Genus:	†Paropsonema Clarke 1900
Type species
†P. cryptophya Clarke 1900
Species[1][2]
†P. cryptophya Clarke 1900  ? †P. mirabile Chapman 1926

A specimen described in 2018 may represent an additional species, but has been tentatively assigned to P. cryptohya;^[3] it represents the youngest described paropsonemid.^[4]

The species Discophyllum mirabile has been thought to be closer to Paropsonema than to the sole previously-described species of Discophyllum, D. peltata.^[5] As a result, sources treat it as Paropsonema mirabile.^[1] Conversely, at least one worker has treated P. cryptophya as a member of Discophyllum, D. cryptophya, although this has not been followed by later authors.^[6] Regardless, Paropsonema and Discophyllum are grouped together informally as "paropsonemids."^[6][1]