Polydora

Polydora cornuta, copyright Erica Keppel.

Belongs within: Spionida.

Polydora is a genus of polychaete worms that often burrow into calcareous substrata such as coral reefs or mollusk shells.

Characters (from Williams 2001): Prostomium with anterior incision or rounded; caruncle extending posteriorly, surrouded by cilia of nuchal organ. Segment 1 without notosetae. Segment 5 modified with one type of major spine in single curved row, with or without companion setae; juveniles may possess large, falcate major spines that are replaced by subsequent spines. Posterior notopodial spines present or absent. Bidentate hooded hooks beginning on segments 7–14, main fang at approximately right angle to shaft, wide angle between main fang and apical tooth, with constriction on shaft. Branchiae beginning posterior to segment 5. Pygidium variable: cuff-shaped, cup-shaped with dorsal gap, lobed, scoop-shaped, or with digitiform cirri. Anterior portion of digestive tract lacking gizzardlike structure.

<==Polydora Bosc 1802 [incl. Leipoceras Möbius 1874, Leucodore Johnston 1838, Protopolydora Czerniavsky 1881] W01
    |--*P. cornuta Bosc 1802 W01
    |--P. agassizi W01
    |--P. aggregata W01
    |--P. caeca Oersted 1843 W01
    |--P. cavitensis W01
    |--P. ciliata (Johnston 1838) [=*Leucodore ciliatus] W01
    |--P. giardi Masnil 1896 RP07
    |--P. hamata Webster 1879 W01
    |--P. hoplura H75
    |--P. limicola W01
    |--P. mabinii Williams 2001 W01
    |--P. neocaeca W01
    |--P. nuchalis W01
    |--P. pacifica W01
    |--P. posthamata Jones 1962 [=P. hamata Langerhans 1880 non Webster 1879, *Protopolydora hamata] W01
    |--P. robi Williams 2000 W01
    |--P. umangivora Williams 2001 W01
    |--‘*Leipoceras’ uviferum Möbius 1874 W01
    |--P. websteri W01
    `--P. woodwicki W01

*Type species of generic name indicated

REFERENCES

[H75] Häntzschel, W. 1975. Treatise on Invertebrate Paleontology pt W. Miscellanea Suppl. 1. Trace Fossils and Problematica 2^nd ed. The Geological Society of America: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[RP07] Rousset, V., F. Pleijel, G. W. Rouse, C. Erséus & M. E. Siddall. 2007. A molecular phylogeny of annelids. Cladistics 23: 41–63.

[W01] Williams, J. D. 2001. Polydora and related genera associated with hermit crabs from the Indo-West Pacific (Polychaeta: Spionidae), with descriptions of two new species and a second polydorid egg predator of hermit crabs. Pacific Science 55 (4): 429–465.