Crinoids

Laudon, Lowell Robert

doi:10.1130/mem67v2-p961

Cited by 13 publications

(3 citation statements)

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“…Perspectives on the importance of predation to crinoid ecology and evolution have changed dramatically since the late twentieth century. With few exceptions (Springer 1926;Ubaghs 1953;Laudon 1957;Kesling 1964), predation on crinoids was largely ignored prior to this time, whereas subsequently it has become relatively common to examine many of the major features in the evolutionary and ecological history of crinoids in the context of predation (Meyer and Macurda 1977;Meyer and Ausich 1983;Lane 1984;Signor and Brett 1984;Meyer 1985;Bottjer and Jablonski 1988;Oji and Okamoto 1994;Baumiller and Gahn 2003;Baumiller et al 2008Baumiller et al , 2010Baumiller 2005, 2010;Sallan et al 2011;Gorzelak et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Reconstructing predation pressure on crinoids: estimating arm-loss rates from regenerating arms

Baumiller¹,

Gahn²

2013

Paleobiology

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The regeneration abilities of crinoids not only are important to understanding crinoid ecology, but also can serve as the basis for assessing the pressure exerted on crinoids by predators both in the Recent and in the geologic past. This is especially true of regenerating arms, because arm loss, and subsequent regeneration, is thought to result from interactions with predators, primarily fish. However, the commonly used regeneration-based proxy for predation pressure (proportion of individuals with regenerating arms) does not provide a measure of the rate at which those events occurred. Here we present a method for reconstructing thearm-loss rate per individual, a more direct proxy of predation pressure. This metric accounts for differences in arm length, arm number, and branching pattern, features highly variable among taxa, among environments, and through geologic time. Normalizing for those characters permits the transformation of observed proportions of regenerating arms to rates that can be compared across samples of morphologically distinct crinoids. Applying this method to a Recent crinoid (Cenometra bella) reveals that this shallow-water comatulid loses arms at a rate of about once every ten days. The same approach reveals that Mississippian shallow-water crinoids (Rhodocrinites kirbyi) experienced arm loss much less frequently, approximately once every 36 days, suggesting that predation pressure on crinoids today is greater than it was in the Mississippian.

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Section: Introductionmentioning

confidence: 99%

Reconstructing predation pressure on crinoids: estimating arm-loss rates from regenerating arms

Baumiller¹,

Gahn²

2013

Paleobiology

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“…10.1, 10.2), and it was also described from the “same horizon” at Whites Creek Spring, Davidson County, Tennessee. Laudon (1957) recorded that M . yandelli from other “Borden bioherms” in Kentucky, but we have not located these collections.…”

Section: Systematic Paleontologymentioning

confidence: 99%

Batocrinidae (Crinoidea) from the Lower Mississippian (lower Viséan) Fort Payne Formation of Kentucky, Tennessee, and Alabama: systematics, geographic occurrences, and facies distribution

2018

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The Batocrinidae are characteristic faunal elements in Lower Mississippian shallow-marine settings in North America. Recent delineation of objectively defined genera allows a reexamination of batocrinid species and their distribution in the Fort Payne Formation (early Viséan, late Osagean), a well-studied array of carbonate and siliciclastic facies. The Fort Payne batocrinid fauna has 14 species assigned to six genera, plus hybrid specimens.Magnuscrinus spinosus(Miller and Gurley, 1895a) is reassigned to its original placement inEretmocrinus. Hybrid specimens (Ausich and Meyer, 1994) are regarded asEretmocrinus magnificus×Eretmocrinus spinosus.Macrocrinus casualisis the dominant species ofMacrocrinusin the Fort Payne, andM.mundulusandM.strotobasilarisare recognized in the Fort Payne Formation for the first time.Magnuscrinus cumberlandensisn. sp. is named, 13 species are designated as junior synonyms, the name for the hybrid specimens is changed toEretmocrinus magnificus×Eretmocrinus spinosus, and the previous occurrences of two species in the Fort Payne are rejected. The Eastern Interior Seaway was a mixed carbonate-siliciclastic setting with both shallow- and deep-water epicontinental sea facies ranging from relatively shallow autochthonous green shales to deep-water turbidite facies.Dizygocrinuswas restricted to shallow-water carbonate and siliciclastic facies,Eutrochocrinuswas restricted to shallow-water carbonate facies, andMagnuscrinuswas restricted to deep-water facies. Species distributions varied fromAbatocrinus steropes,Alloprosallocrinus conicus,Macrocrinus mundulus, andUperocrinus nashvillae, which occurred throughout the Eastern Interior Seaway, to species that were restricted to a single facies.Eretmocrinus magnificus,Alloprosallocrinus conicus, andUperocrinus robustuswere the dominant batocrinids in the Fort Payne Formation.UUID:http://zoobank.org/703aafd8-4c73-4edc-9870-e2356e2d28b8

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“…Baumiller (2008) explained that up until 1920 crinoids were thought to be "immune" from predation, but modern investigation has proven otherwise. Laudon (1957) projected that a scarcity of crowns and intact thecal plates, leaving only columnals behind, was evidence of grazing by predators. Springer (1920) and Hattin (1958) included regenerated arms and Ubaghs (1978) included the autotomy of arms regeneration as a common finding.…”

Section: Adaptationmentioning

confidence: 99%

Systematics and evolutionary paleoecology of crinoids from the St. Louis Limestone (Mississippian, Meramecian) of the Illinois Basin

Cook¹

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Systematics and Evolutionary Paleoecology of Crinoids from the St. Louis Limestone (Mississippian, Meramecian) of the Illinois Basin Lewis A. Cook Very little attention has been paid to crinoids of the St. Louis Limestone since the 19 th century. Now that the stratigraphic boundaries of the formation are well defined and a collection of crinoids specific to the St. Louis has become available, updated systematics and evolutionary paleoecology is possible. Previous work recognized a significant transition in the macroevolution of crinoids that occurred during the Mississippian Period. The diversity of crinoid taxa changed substantially from faunas dominated by camerates and primitive cladids to those dominated by advanced cladids. Much of that change took place during the Meramecian Stage, which includes the St. Louis Limestone. The preceding Salem Limestone contained a prevalence of camerates whereas the following superjacent Ste. Genevieve Limestone contained a more advanced cladids. Questions that are considered include: what changes in morphology of crinoids accompanied that transition; what, if any, environmental change occurred that influenced the major transition in crinoids; and what was the precise change in the distribution of crinoid taxa throughout the deposition of the St. Louis Limestone? The approach to providing a plausible description and explanation includes an evaluation of the geologic setting, a re-evaluation of crinoid systematics, and an investigation of the evolutionary paleoecology of the St. Louis Limestone crinoids. Lithology of the St. Louis Limestone is compared to the Salem Limestone below and the Ste. Genevieve limestone above. A change in environment occurred within the St. Louis. The Salem and Ste. Genevieve were deposited in a deeper water setting, whereas St. Louis deposition took place in a low-energy, mostly lagoonal setting. This is reflected in microscopic study by the prevalence of mudstone and wackestone in the St. Louis while ths Salem and St. Genevieve are granistones Systematic evaluation confirmations 17 species of crinoids previously assigned to the St. Louis. Three crinoid species that were identified within other formations, but not in the St. Louis, were added. One new species, Armenocrinus howelli was identified. Three species were synonymized within the St. Louis. Eight species previously listed as belonging to the St. Louis were found to be incorrectly assigned. Crinoids had been adapting in their overall morphology prior to the Meramecian. Various changes in feeding structures, predatory defenses and mobility occurred from the Ordovician through the early Meramecian. Those adaptations allowed crinoids with the most advantageous morphology to survive adverse environmental conditions. In fact, two events took place during the Meramecian that would have impacted the survival of crinoids. Durophagous predators increased in numbers and a prolonged regression reduced habitat area during the deposition of the St. Louis. Those two factors impacted crinoids in a negative ...

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Crinoids

Cited by 13 publications

References 0 publications

Reconstructing predation pressure on crinoids: estimating arm-loss rates from regenerating arms

Reconstructing predation pressure on crinoids: estimating arm-loss rates from regenerating arms

Batocrinidae (Crinoidea) from the Lower Mississippian (lower Viséan) Fort Payne Formation of Kentucky, Tennessee, and Alabama: systematics, geographic occurrences, and facies distribution

Systematics and evolutionary paleoecology of crinoids from the St. Louis Limestone (Mississippian, Meramecian) of the Illinois Basin

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