Paleoallium: Difference between revisions

The first illustration of a fossil was in the 2011 ''Fossil plants from Republic: a guidebook'' published for the [[Stonerose Interpretive Center]] where specimen SR 08-36-03 was figured as an "additional flower". The Allenby Formation specimen noted as similar to ''Paleoallium'' was figured as an "Unknown structure" by Dilhoff ''et al'' (2013). A series of the fossils were formally studied by paleobotanists Kathleen Pigg, Finley Bryan, and Melanie DeVore who published their formal description of the genus and species in a 2018 ''[[International Journal of Plant Sciences]]'' paper.<ref name="Pigg2018"/> Pigg, Bryan, DeVore designated the [[holotype]] as specimen SR 10-35-06, which was in the [[paleobotany|paleobotanical collections]] of the Stonerose Interpretive Center in Republic at that time. An additional [[paratype|paratype series]] of 15 fossils, also from the Stonerose collections, was designated, and one additional fossil, SR 13-004-010 A&B was discussed and figured, but not included in the type series. The [[Botanical name#Components of plant names|genus name]] ''Paleoallium'' was created as a combination of "''[[Allium]]''", the modern garlic & onion genus, plus the prefix ''paleo-''. They noted "''Allium''" is a reference to the remarkable similarity between the fossils and modern onions, but they specified there is no direct implied relationship between any living species discussed in the paper.<ref name="Pigg2018"/> The species name ''billgenseli'' as a [[patronym]] honoring William Gensel, [[Durham, North Carolina]] botanist who first pointed to the similarity between alliums and the fossils and for his larger contributions to plant sciences.<ref name="Pigg2018"/>

Since being described, ''Paleoallium billgenseli'' has been used a number of times as a [[Molecular clock|molecular dating]] calibration point for the origins and divergence of Amaryllidaceae. The genus is noted for being the first [[Amaryllidaceae]] from the fossil record.<ref name="Xie2020">{{cite journal |last1=Xie |first1=D.F. |last2=Tan |first2=J.B. |last3=Yu |first3=Y. |last4=Gui |first4=L.J. |last5=Su |first5=D.M. |last6=Zhou |first6=S.D. |last7=He |first7=X.J. |year=2020 |title=Insights into phylogeny, age and evolution of ''Allium'' (Amaryllidaceae) based on the whole plastome sequences |journal=Annals of Botany |volume=125 |issue=7 |pages=1039-10551039–1055 |doi=10.1093/aob/mcaa024|pmid=32239179 |pmc=7262478 }}</ref><ref name="Han2020">{{cite journal |last1=Han |first1=T.S. |last2=Zheng |first2=Q.J. |last3=Onstein |first3=R.E. |last4=Rojas‐AndrésRojas-Andrés |first4=B.M. |last5=Hauenschild |first5=F. |last6=Muellner‐RiehlMuellner-Riehl |first6=A.N. |last7=Xing |first7=Y.W. |year=2020 |title=Polyploidy promotes species diversification of ''Allium'' through ecological shifts |journal=New Phytologist |volume=225 |issue=1 |pages=571-583571–583 |doi=10.1111/nph.16098|pmid=31394010 |hdl=10366/154734 |hdl-access=free }}</ref><ref name="Namgung2021">{{cite journal |last1=Namgung |first1=J. |last2=Do |first2=H.D.K. |last3=Kim |first3=C. |last4=Choi |first4=H.J. |last5=Kim |first5=J.H. |year=2021 |title=Complete chloroplast genomes shed light on phylogenetic relationships, divergence time, and biogeography of Allioideae (Amaryllidaceae) |journal=Scientific Reports |volume=11 |issue=1 |pages=3262. |doi=10.1038/s41598-021-82692-5|pmid=33547390 |pmc=7865063 |bibcode=2021NatSR..11.3262N }}</ref><ref name="Howard2020">{{cite journal |last1=Howard |first1=C.C. |last2=Cellinese |first2=N. |year=2020 |title=Tunicate bulb size variation in monocots explained by temperature and phenology |journal=Ecology and Evolution |volume=10 |issue=5 |pages=2299-23092299–2309|doi=10.1002/ece3.5996 |pmid=32184982 |pmc=7069286 |bibcode=2020EcoEv..10.2299H }}</ref>

''Paleoallium billgenseli'' [[spathe]]s are between {{cvt|3-8|mm|in|frac=8}} wide and {{cvt|5-12|mm|in|frac=8}} long, granting an obovate to elliptically ovate outline. They range from sprouting flat from the scape to sprouting at a right angle to the spathe length. On well preserved specimens, the surfaces show parallel striations running from base to apex. Two sets of reproductive structures have been identified at the spathe apices, -flowers and [[bulbil]]s. The flowers are usually born in groups of two to six grouped in a helical arrangement near the spathe apex. Each bell shaped flower is born on a small [[Pedicel (botany)|pedicel]] typically between {{cvt|2-8|mm|in|frac=8}} long. The bell is composed of three to four lobes and is {{cvt|3–6|mm|in|frac=8}} wide by {{cvt|4–8|mm|in|frac=8}} long. Careful preparation of several flowers did not find any fruits, seeds, pollen or anthers, suggesting the possibility the flowers were sterile. Some specimens have distinctly elongated pedicels and either small aborted flowers or buds. The bulbils are sessile around the apex of the scape, in confirmed groups of one to three. There is the possibility that higher numbers may have been borne, but if so, the Authors noted they may have been lost during specimen preparation or obscured under layers of matrix rock. The known bulbils range up to {{cvt|1x0.2|mm|in|frac=64}} in size.<ref name="Pigg2018"/>

Of the known specimens, the [[Scape (botany)|scapes]] are elongate and narrow, ranging between {{cvt|18–40|mm|in|frac=8}} long by {{cvt|0.8–1.2|mm|in|frac=64}} wide. All specimens have a torn scape base and none are attached to a bulb. They have longitudinal striations as is seen in some onion species and occasionally the apical area will have wisps of tissues around the spathe base, suggested to be outer "onion skin" layers.<ref name="Pigg2018"/>

{{Taxonbar|from=Q124422014}}

[[:Category:Amaryllidaceae|†Paleoallium]]

[[:Category:Plants described in 2018]]

[[:Category:Fossil taxa described in 2018]]

[[:Category:FernsFlora of the Northwestern United States]]

[[:Category:FernsFlora of Western Canada]]

[[:Category:Flora of the Northwestern UnitedYpresian Statesplants]]

[[:Category:FloraEocene plants of WesternNorth CanadaAmerica]]

[[:Category:YpresianKlondike Mountain plantsFormation]]

[[:Category:Eocene plants of NorthAllenby AmericaFormation]]

[[:Category:KlondikePrehistoric Mountainangiosperm Formationgenera]]

[[:Category:AllenbyAmaryllidaceae Formationgenera]]