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Alkaidia

Asteroidea - Notomyotida - Benthopectinidae

Taxonomy
Alkaidia was named by Blake and Reid (1998). It is not extant. Its type is Alkaidia sumralli.

It was assigned to Paleobenthopectininae by Blake and Reid (1998); and to Notomyotida by Sepkoski (2002).

Synonymy list
YearName and author
1998Alkaidia Blake and Reid p. 529 fig. 9
2002Alkaida Sepkoski, Jr.

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RankNameAuthor
kingdomAnimalia()
Triploblastica
Nephrozoa
Deuterostomia
Ambulacraria
phylumEchinodermata
subphylumAsterozoa
classAsteroidea
RankNameAuthor
subclassAmbuloasteroidea
infraclassNeoasteroidea()
superorderValvatacea
orderNotomyotida
familyBenthopectinidae
subfamilyPaleobenthopectininae
genusAlkaidia

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Diagnosis
ReferenceDiagnosis
D. B. Blake and R. Reid 1998Paleobenthopectinid with thick arms, attenuated arm tips. Carinals, laterals both large, flat, cross-shaped, articular facets prominent; one lateral row on each side of carinals reaching arms tips. Marginals flat, triangular, with very large spine bases; marginals flat, triangular, flat, with very large spine bases; marginal spines flat, pointed, about 3.5 mm long in holotype. Robust 3-piece Pedicellariae on dorsal arm surfaces, possibly ventral as well. Proximal adambulacrals with single enlarged subambulacral spine.