When described
Formicodiplogaster myrmenema was described from approximately seven fossil nematodes which were group
inclusions with ants in transparent chunks of
Dominican amber. The amber dates from at least the
Burdigalian stage of the Miocene, based on studying the associated fossil
foraminifera and may be as old as the Middle Eocene, based on the associated fossil
coccoliths. This age range is due to the host rock being secondary deposits for the amber, and the Miocene the age range is the youngest that it might be. At the time of description, the
holotype dauer stage larva, in addition to the
paratype larvae, adults and juveniles, were preserved in the Poinar amber collection at
Oregon State University. The fossils were first studied by paleontologist
George Poinar Jr. of Oregon State University, with his 2011
type description of the new genus and species being published in the journal
Nematology monographs and perspectives pages. The
generic epithet Formicodiplogaster is derived from the
Latin formica, meaning "ant", and the nematode genus
Diplogaster, while the specific epithet is a derivation of the
Greek myrmex, meaning ant, and
nema, meaning "thread". Portions of ant nests have been fossilized and identified and show an association of the extinct ant
Azteca alpha colonies and
Formicodiplogaster myrmenema. The nests show active ant colonies in which adult and juvenile
F myrmenema are present. Examples of
phoretic F myrmenema are preserved as individuals in a
dauer stage that was possibly carried in the abdominal intersegment membranes. The transition and transport of the dauer stage
F myrmenema may have been a result of deteriorating conditions in the host colony. No direct evidence has been found for
F. myrmenema living in the postpharyngeal glands or head glands of
A. alpha. ==Description==