The phylogenetic relationships of
Prionospio Malmgren, 1867 are estimated in two parsimony analyses. The first analysis includes type and other species of
Prionospio (Prionospio) Malmgren. 1867.
P. (Minuspio) Foster, 1971,
P. (Aquilaspio) Foster, 1971,
Apoprionospio Foster, 1969,
Aurospio Maciolek, 1981,
Paraprionospio Caullery, 1914,
Streblospio Webster, 1897,
Laubieriellus Maciolek, 1981, and
Orthoprionospio Blake & Kudenov, 1978; all members of a group of closely related taxa.
Prionospio banyulensis Laubier, 1966 is included as a separate taxon since its relationship to
Prionospio has been questioned. The single most parsimonious tree supports monophyly of a group containing
P. (Prionospio),
P. (Minuspio),
P. (Aquilaspio), and
Apoprionospio.
Based on the tree topology from the first analysis, 14 species belonging to different subgenera of
Prionospio and
Apoprionospio are included in a more restricted analysis, with
Orthoprionospio cirrformia Blake & Kudenov, 1978 as outgroup. Three equally parsimonious trees were obtained, differing only in the positions of
Prionospio ehlersi Fauvel, 1928,
Prionospio henriki Hylleberg & Nateewathana, 1990, and
Prionospio rugosa Sigvaldadóttir, 1997.
The results of the two analyses are compared to earlier classifications. As support is lacking for monophyly of both subgenera
P. (Minuspio) and
P. (Aquilaspio), they are synonymized with
P. (Prionospio).
Apoprionospio cannot be justified as a separate genus without making
Prionospio paraphyletic, and is synonymized with
Prionospio. Two species,
P. banyulensis and
P. pilkena Wilson, 1990, are transferred to
Aurospio. A checklist of species belonging to
Prionospio sensu lato, together with information on type locality and location of type specimens, is included.
