Protodriliformia

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Protodriliformia
Protodrilus (YPM IZ 072370) 002.jpeg
Protodrilus mirabilis
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Annelida
Clade: Pleistoannelida
Subclass: Errantia
Clade: Protodriliformia
Struck et al. 2015 [1]
Orders and families

Protodriliformia is a clade of small marine polychaetes, comprised by the groups of meiofaunal interstitial worms Protodrilida and Polygordiidae, formerly considered "archiannelids". It is the most basal clade of Errantia. [1] [2]

Evolutionary history

Phylogenetic analysis of annelids has found Protodriliformia to be the earliest diverging clade of Errantia. At the same time, the other half of "archiannelid" worms, Orbiniida, was found to be the earliest diverging clade of Sedentaria. The convergence between these two groups occurred through progenesis and miniaturization, as a way to adapt to the marine interstitial ecosystem between sand grains (i.e. interstitium). This means that the larval or juvenile stages of a larger pleistoannelid ancestor temporarily inhabiting the interstitium stopped their somatic growth, became sexually mature and stayed in the interstitium permanently. [1]

Pleistoannelida

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<span class="mw-page-title-main">Clitellata</span> Class of annelid worms

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<span class="mw-page-title-main">Orbiniida</span> Order of annelid worms

Orbiniida is an order of small polychaete worms in the phylum Annelida. It is the earliest diverging clade in Sedentaria. Along with Protodriliformia, this order is composed of meiofaunal marine worms formerly known as "archiannelids". These worms inhabit the marine interstitial ecosystem, the space between sand grains.

References

  1. 1 2 3 Struck TH, Golombek A, Weigert A, Franke FA, Westheide W, Purschke G, Bleidorn C, Halanych KM (3 August 2015). "The evolution of annelids reveals two adaptive routes to the interstitial realm". Curr Biol. 25 (15): 1993–1999. doi: 10.1016/j.cub.2015.06.007 . PMID   26212885.
  2. Struck TH (2019). "Phylogeny". In Purschke G, Böggemann M, Westheide W (eds.). Handbook of Zoology: Annelida. Vol. 1: Annelida Basal Groups and Pleistoannelida, Sedentaria I. De Gruyter. doi:10.1515/9783110291582-002. ISBN   9783110291469.