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Node. Heterorhabditidae
Taxon. Proheterorhabditis burmanicus
Host. Rove beetle (Staphylinidae)
Phylogenetic justification. Their size, ensheathing cuticle with longitudinal striations and small terminal tooth align these fossils interpreted as third-stage juvenile with heterorhabditids (Poinar 2011). The presence of bacterial cells in the
body cavity similar in size to that of modern representatives also strengthens this
interpretation (Poinar 2015).
Minimum age. 98.17 Ma. See Tylenchomorpha for justification.
Juveniles of the parasitic Palaeocosmocerca burmanicum adjacent to a snail in
Burmese amber are considered the oldest fossil evidence of family Cosmocercidae
(Poinar 2011).
Node. Cosmocercidae
Taxon. Palaeocosmocerca burmanicum
Fossil Evidence. Worm bodies associated with putative host in Burmese Amber
(Poinar 2011).
Host. Unidentified snail
Phylogenetic Justification. The morphological characteristics of the second-stage
juveniles (offset lips, flat head, constricted anterior portion of the pharynx) and
dimensions of pre-infective stages are similar to extant Cosmocercidae—
particularly Cosmocercoides dukae (Poinar 2011)
Minimum age. 98.17 Ma. See Tylenchomorpha for justification
Howardula helenoschini from Baltic amber, considered to belong to
Allonematidae (Poinar 2003b), provides the oldest evidence for the presence of
animal parasitism in Tylenchomorpha (Poinar 2011, 2015). Other evidence for the
presence of this order in the fossil record is Paleoiotonchium dominicanum parasitizing a fungus gnat in Dominican amber and a population of Oligaphelenchoides
atrebora from Mexican amber (Poinar 2011). The former might represent the oldest
fossil evidence for the presence of separate life cycles between fungal gnats and
fungi in Iotonchidae (Poinar 2011). The latter consist of eggs, juvenile and adults,
together with fungal hyphae, providing further evidence for mycophagy in the family Aphelenchoididae (Poinar 2015).
Direct evidence for filariid nematodes goes back to Baltic amber and Dominican
amber (Poinar 2015). Their size, shape and ornamentation speak for their identification as filariid nematodes. Horizontal transfers of retroposons suggest that at some
time filariids were likely parasitizing tropical birds rather than mammals, thus constraining them to a time interval which at least partially overlaps with the age estimates of Dominican amber (Suh et al. 2016; Suh 2021). In addition to filarial
remains, also tropical bird remains (Poinar et al. 2007) have been reported from
Dominican amber, suggesting they at least were present at the same time in the
same region.
Node. Filarioidea
Fossil Taxon. Cascofilaria baltica
K. De Baets et al.
Node. Heterorhabditidae
Taxon. Proheterorhabditis burmanicus
Host. Rove beetle (Staphylinidae)
Phylogenetic justification. Their size, ensheathing cuticle with longitudinal striations and small terminal tooth align these fossils interpreted as third-stage juvenile with heterorhabditids (Poinar 2011). The presence of bacterial cells in the
body cavity similar in size to that of modern representatives also strengthens this
interpretation (Poinar 2015).
Minimum age. 98.17 Ma. See Tylenchomorpha for justification.
Juveniles of the parasitic Palaeocosmocerca burmanicum adjacent to a snail in
Burmese amber are considered the oldest fossil evidence of family Cosmocercidae
(Poinar 2011).
Node. Cosmocercidae
Taxon. Palaeocosmocerca burmanicum
Fossil Evidence. Worm bodies associated with putative host in Burmese Amber
(Poinar 2011).
Host. Unidentified snail
Phylogenetic Justification. The morphological characteristics of the second-stage
juveniles (offset lips, flat head, constricted anterior portion of the pharynx) and
dimensions of pre-infective stages are similar to extant Cosmocercidae—
particularly Cosmocercoides dukae (Poinar 2011)
Minimum age. 98.17 Ma. See Tylenchomorpha for justification
Howardula helenoschini from Baltic amber, considered to belong to
Allonematidae (Poinar 2003b), provides the oldest evidence for the presence of
animal parasitism in Tylenchomorpha (Poinar 2011, 2015). Other evidence for the
presence of this order in the fossil record is Paleoiotonchium dominicanum parasitizing a fungus gnat in Dominican amber and a population of Oligaphelenchoides
atrebora from Mexican amber (Poinar 2011). The former might represent the oldest
fossil evidence for the presence of separate life cycles between fungal gnats and
fungi in Iotonchidae (Poinar 2011). The latter consist of eggs, juvenile and adults,
together with fungal hyphae, providing further evidence for mycophagy in the family Aphelenchoididae (Poinar 2015).
Direct evidence for filariid nematodes goes back to Baltic amber and Dominican
amber (Poinar 2015). Their size, shape and ornamentation speak for their identification as filariid nematodes. Horizontal transfers of retroposons suggest that at some
time filariids were likely parasitizing tropical birds rather than mammals, thus constraining them to a time interval which at least partially overlaps with the age estimates of Dominican amber (Suh et al. 2016; Suh 2021). In addition to filarial
remains, also tropical bird remains (Poinar et al. 2007) have been reported from
Dominican amber, suggesting they at least were present at the same time in the
same region.
Node. Filarioidea
Fossil Taxon. Cascofilaria baltica
K. De Baets et al.