Patiriella, Verrill, 1913

O'Loughlin, P. M., Waters, J. M. & Roy, M. S., 2003, A molecular and morphological review of the asterinid, Patiriella gunnii (Gray) (Echinodermata: Asteroidea), Memoirs of Museum Victoria 60 (2), pp. 181-195 : 183

Key to six-rayed species of Patiriella

1. Subambulacral spines predominantly 1 per plate, up to twice length of adradial actinal spines; actinal interradial spines very short, frequently bulbous; abactinal surface uneven; abactinal spinelets prominently spinous, frequently low to subcapitate; proximal papular spaces large, frequently with more than 10 secondary plates and more than 10 papulae per space when R = 30 mm; abactinal colour of adults consistently uniform crimson to brownish red, tube feet orange..... Patiriella gunnii ( Gray, 1840)

— Subambulacral spines predominantly 2–3 per plate, not up to twice the length of adradial actinal spines; actinal interradial spines not very short or bulbous; abactinal surface even; abactinal spinelets moderately to minutely spinous, frequently columnar; proximal papular spaces not large, fewer than 10 secondary plates and 10 papulae per space when R = 30 mm; abactinal colour variable, not uniform crimson to brownish red, with orange tube feet...... 2

2. At least a few suboral spines frequently present; adradial actinal spines up to about two-thirds length of subambulacral spines; actinal interradial spines short and fine; carinal plates normally doubly papulate for less than two-thirds ray length, frequently less than half ray length; proximal papular spaces small, frequently up to 3 secondary plates and 3 papulae per space when R = 30 mm; abactinal spinelets relatively small and fine, predominantly narrowing distally, minutely spinous; abactinal colour variable, frequently overall maroon red (not reported with grey or blue, or with black disc); actinal colour off-white, frequently with prominent flecking......................................... Patiriella medius sp. nov.

— Suboral spines rarely present; adradial actinal spines frequently more than two-thirds length of subambulacral spines; actinal interradial spines digitate; carinal plates normally doubly papulate for more than half ray length, frequently more than two-thirds ray length; proximal papular spaces fairly open, frequently with about 6 secondary plates and 6 papulae per space when R = 30 mm; abactinal spinelets relatively coarse, predominantly columnar, slightly narrowing to slightly widening distally, moderately spinous; abactinal colour variable, not overall maroon red................................. 3

3. Form variable, commonly distinctive short rays with interradial margin deeply indented; subambulacral spines frequently projecting fairly prominently; abactinal spinelets coarse, columnar, moderately spinous, frequently widened distally; up to about 8 spinelets on inferomarginal plates when R = 20 mm, up to about 11 when R = 30 mm; abactinal colour frequently dark, with grey or brown or blue, infrequently with red.. Patiriella occidens sp. nov.

— Form variable, commonly subhexagonal with interradial margin slightly incurved; subambulacral spines not projecting significantly; abactinal spinelets fairly coarse, columnar, moderately spinous, frequently narrowing distally, up to about 10 spinelets on inferomarginal plates when R = 20 mm, up to about 15 when R = 30 mm; abactinal colour frequently pale, with white or pink or mauve or orange or bright red, disc frequently black (not reported with grey (except in NSW), or blue)......................................... Patiriella oriens sp. nov.