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Abundant new material of articulated asteroids from the Taba Starfish Bed (Lower Cretaceous, Barremian) of the Agadir Basin, western Morocco, allows reappraisal of this important fauna, and the recognition, to date, of five taxa belonging to the Astropectinidae, Odontasteridae, Goniasterididae, Terminasteridae, and Asteriidae.Betelgeusia orientalisBlake and Reboul, 2011 is shown to be a junior synonym ofCoulonia platyspinaHess and Blake, 1995, andDipsacaster africanusBlake and Reboul, 2011 comprises material ofC.platyspinaand a new odontasterid, here described asOdontaster tabaensisn. sp.Alkaidia megaungulan. sp. is described and its ontogeny and affinities discussed. From this, it is concluded that the Terminasteridae, revised to include the generaTerminasterandAlkaidia, is sister taxon to the extant family Zoroasteridae, and both are placed in the suborder Zorocallina of the Forcipulatida. The Taba fauna is a representative of a distinctive Lower Cretaceous asteroid assemblage that existed in northern Tethys from the Barremian to the Cenomanian and is also well known from the Albian and lower Cenomanian of Texas.UUID:http://zoobank.org/b2ecdd06-685d-4242-9e49-985f9d7a3cc1

A new Late Jurassic (Oxfordian) asteroid (Echinodermata) faunule from the Swift Formation of Montana includes representatives of four genera including the new genus and speciesAtalopegaster gundersoni(Stichasteridae),Eokainastersp. indet. (Astropectinidae), an indeterminate probable member of the Goniasteridae, and a species indeterminate beyond the class level. Because of weathering at the outcrop, preservation is poor.Although representing an unusual depositional occurrence, overall faunule composition appears comparable to that found in a similar modern environment. The faunule is comparable in age and regional location to earlier Jurassic asteroid discoveries, suggesting wide distribution during a geologically brief time interval of favorable conditions. Asteroids are only rarely reported from the Mesozoic of the North American continental interior, and co-occurrence of multiple fossil taxa is unusual on a global basis.

An asteroid (Echinodermata) faunule of four taxa representing three surviving families and a probable fourth is described from the Barremian (Early Cretaceous) of Morocco, northwest Africa. The four together suggest limited morphologic evolution since the Cretaceous but biogeographic and depth patterns have changed. Marocaster coronatus n. gen. n. sp. (Valvatida, Goniasteridae) combines apparent derived features of the dorsal disk and superomarginal shape with more stemward expressions of the abactinal ossicles. Betelgeusia orientalis n. sp. is a fourth Mesozoic occurrence of the Radiasteridae (Paxillosida), the new species similar to earlier occurrences from the Middle Jurassic of India, the Early Cretaceous of Texas, and the Late Cretaceous of Europe. Reported modern occurrences of the family are few, widely scattered, and limited to deeper water; the extinct species together testify to a once-broader familial distribution. Dipsacaster africanus n. sp., a member of the Astropectinidae (Paxillosida), is remarkably similar to extant congeners. Dipsacaster today is widely distributed in the Pacific Ocean but occurrences in the Atlantic are few. Because of preservation, a single small specimen of the Zoroasteridae? (Forcipulatida) cannot be identified with certainty. Extant zoroasterids are deep-water in distribution, although shallow-water Eocene representatives are known.

An asteroid fauna is described from the Albian (Cretaceous) interval of the Washita Group of central Texas. New genera and species areAlkaidia sumralli, (Benthopectinidae),Capellia mauricei(Goniasteridae), andBetelgeusia reidi(Radiasteridae). Additional new genera areFomalhautia(Goniasteridae), andDenebiaandAltairia(Ophidiasteridae).Crateraster texensis(Goniasteridae), new combination, is similar to the European type species,C. quinqueloba.An unnamed species ofCraterasterand an unassigned goniasterid are also present. All Washita genera are extinct, but all belong to extant families. The fauna is largely distinct from that of the somewhat younger European Cretaceous chalk.The Radiasteridae (e.g.,Betelgeusia) is inferred to hold a basal position in the Paxillosida;Betelgeusiaextends the range of the family back to the Cretaceous, closer to the diversification of the living asteroid orders. Asteroids capable of burying themselves in sediment (and only self-buriers) share some form of channelization for the passage of water currents between the primary ossicles of the body surface. Channels inBetelgeusiaindicate semi-infaunal habits similar to those of livingAstropectenandLuidia. Betelgeusiarepresents the third semi-infaunal paxillosidan family now known from the Cretaceous, although none are known from older rocks, suggesting a broadening of the asteroid adaptive zone during the Cretaceous. The Goniasteridae, Radiasteridae, and Benthopectinidae are less important in shelf settings today than they appear to have been during Washita deposition, whereas the Astropectinidae, Luidiidae, and the Echinasteridae are absent from the Washita although they are common today in similar settings.

Aldebarania arenitea (Astropectinidae; Asteroidea; Echinodermata) is described from the Rocky Point Member of the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina. A turbulent, shallow-water environment is suggested by sedimentary features, a diverse marine fauna, and the morphology of Aldebarania. Aldebarania appears to be a partial ecological equivalent of living Astropecten and Luidia; however, phylogenetic relationships within the Astropectinidae are unstudied and the origin of similarities is unknown.

Although many of the surviving lineages of sea stars appeared during an early Mesozoic radiation of the class and have undergone limited change since then, they have left a very poor fossil record, particularly in the Mesozoic of North America (Blake, 1981). This record from the Late Cretaceous of Alberta is made more significant by the fact that it is apparently only the second occurrence of a member of the family Astropectinidae in the Cretaceous of North America; Lophidiaster silentiensis was described by McLearn (1944) from the Lower Cretaceous (Albian) Hasler Formation, from a now-submerged locality on the Peace River in northern Alberta. All previously recorded fossil sea stars from the North American Cretaceous are representatives of the family Goniasteridae.

Examination of the reproductive biology of three closely related sympatric astropectinid asteroidshas revealed two distinct reproductive strategies. In Plutonaster bifrons and Dytaster insignis the gonads are serially arranged and open at gonopores located at the tip of genital papillae found on the dorsal arm surface between the bases of the paxillae. The ovaries of these species produce numerous small (ca. 120/«n diameter) eggs which in Plutonaster bifrons appear to show a distinct synchrony of production. Initiation of gametogenesis occurs in June to August of each year with oocyte growthcontinuing until March with a spawn-out in the period March to early June. In specimens where spawningdoesnot occur, there would appear to be internal oocyte degeneration, or after spawning relict oocytesundergo phagocytosis. In males initiation of spermatogenesis may occur in August/September of eachyear but after this synchrony of sperm development is not evident. In Psilaster andromeda gonads are located at the base of the arms and each gonad opens at a single gonopore. A number of small (