Identification Resources
Taxonomy based on fused jaw apparatus is extremely crucial in correct identification of polychaete worms (Eriksson & Bergman, 1998). The combination of two taxonomic systems (general morphology and jaw morphology) has been debated at length and resulted in some major taxonomic revision in the past two decades as the same species may have been described multiple times using different systems of classification (Eriksson & Bergman, 1998). In combining both systems it is possible to relate polychaete morphology to its size, function and anatomical arrangement (Eriksson & Bergman, 1998).
The habitat in which the worm is found, the presence or absence of jaws, a muscular and/or eversible pharynx and the form of numerous appendages including number of segments, presence or absence of antennae, presence of absence of tentacular cirri and the morphology of the parapodia are extremely important for identification purposes. The number and forms of pharyngeal papillae and paragnaths as well as observing the number and morphology of parapodial lobes and type of chaetae on the anterior, mid-section and posterior of the organism are important in determining the genus and species of a polychaete (Beesley et al., 2000).
The study organism from the genus Perenereis can be distinguished from other polychaete taxa by some unique, key characteristics:
| Two antennae |
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| Four pairs of tentacular cirri |
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| Two pairs of simple eyes (ocelli) |
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| Conical paragnaths on maxillary and oral ring (ventral) |
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| Transverse bar paragnaths on oral ring (dorsal) |
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| Parapodia which are typically biramous (except first two uniramous setigers) |
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Some polychaetes are unique and easily recognisable but others may be difficult to identify especially to the level of genera and species. Some polychaete identification keys are available online:
Other resources are more difficult to obtain but include:
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Polychaetes & Allies: The Southern Synthesis. Fauna of Australia (edited by Beesley et. al., 2000)
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Invertebrate Zology: A Functional Evolutionary Approach (Ruppert et al., 2004)
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