Boreostemma

{{Automatic taxobox

| fossil_range = Mid Miocene-Early Pliocene (Laventan-Montehermosan)
~{{fossil range|13|5}}

| image = Boreostemma tail - Honda Group - Colombia.jpg

| image_caption = Tail of Boreostemma from the Honda Group

| taxon = Boreostemma

| authority = Carlini et al. 2008

| subdivision_ranks = Species

| subdivision =

B. acostae {{small|Villarroel 1983}}
B. gigantea {{small|Carlini et al. 1997}}
B. pliocena {{small|Carlini et al. 2008}}
B. venezolensis {{small|Simpson 1947}}

| type_species = †Boreostemma pliocena

| type_species_authority = Carlini et al. 2008

}}

Boreostemma is an extinct genus of glyptodonts from northern South America. Fossils assigned to the genus were first described as belonging to Asterostemma from southern South America, but have been placed in the new genus Boreostemma by Carlini et al. in 2008. The type species is B. pliocena. Fossils of Boreostemma have been found in the Honda Group of Colombia, in Peru and Venezuela.

Etymology

The genus name Boreostemma is a combination of stemma, taken from Asterostemma, and boreo is derived from borealis, meaning "northern", to distinguish the northern South American genus from the southern Asterostemma.{{Sfn|Carlini|Zurita|Scillato Yané|Sánchez|2008|p=142}}

Taxonomy

Boreostemma has been placed as closely related to the later Glyptodon and Glyptotherium. Cladogram after Barasoain et al. 2022:{{Cite journal |last1=Barasoain |first1=Daniel |last2=Zurita |first2=Alfredo E. |last3=Croft |first3=Darin A. |last4=Montalvo |first4=Claudia I. |last5=Contreras |first5=Víctor H. |last6=Miño-Boilini |first6=Ángel R. |last7=Tomassini |first7=Rodrigo L. |date=June 2022 |title=A New Glyptodont (Xenarthra: Cingulata) from the Late Miocene of Argentina: New Clues About the Oldest Extra-Patagonian Radiation in Southern South America |url=https://link.springer.com/10.1007/s10914-021-09599-w |journal=Journal of Mammalian Evolution |language=en |volume=29 |issue=2 |pages=263–282 |doi=10.1007/s10914-021-09599-w |issn=1064-7554 |s2cid=245945029|url-access=subscription }}{{clade|{{clade

|label1=Traditional Glyptodontinae

|1={{clade

|1=Boreostemma

|2={{clade

|1=Glyptotherium

|2=Glyptodon

}}}}

|label2="Austral clade"

|2={{clade

|1=Propalaehoplophorus

|2={{clade

|1=Eucinepeltus

|2={{clade

|1=Cochlops

|2=Palaehoplophorus

|3={{clade

|1=Kelenkura

|2={{clade

|1=Eosclerocalyptus

|2={{clade

|1={{clade

|1=Plohophorus

|2=Pseudohoplophorus

}}

|label2=Doedicurinae

|2={{clade

|1=Doedicurus

|2=Eleutherocercus

}}

|2={{clade

|1=Neosclerocalyptus

|label2=Hoplophorini

|2={{clade

|1=Hoplophorus

|2={{clade

|1=Propanochthus

|2=Panochthus

}}}}}}}}}}}}}}}}}}}}|label1=Glyptodonts}}

= Species =

{{Location map+ | South America

| relief = 1

| width = 225

| caption = Locations of Boreostemma and Asterostemma fossil finds in South America
10px Asterostemma
10px B. acostae & B. gigantea
10px B. pliocena (type)
10px B. venezolensis
10px Boreostemma sp.

| places =

{{Location map~ | South America

| lat_deg = -50.4

| lon_deg = -69.1

| mark = Brown pog.svg

| marksize = 10

| link = Santa Cruz Formation, Argentina

}}

{{Location map~ | South America

| lat_deg = -10.1

| lon_deg = -66.9

| mark = Brown pog.svg

| marksize = 10

| link = Solimões Formation

}}

{{Location map~ | South America

| lat_deg = 5.191944

| lon_deg = -74.7225

| mark = Orange pog.svg

| marksize = 10

| link = Honda Group, Colombia

}}

{{Location map~ | South America

| lat_deg = 11.3

| lon_deg = -70.3

| mark = Yellow pog.svg

| marksize = 12

| link = Codore Formation

}}

{{Location map~ | South America

| lat_deg = 9.0

| lon_deg = -64.8

| mark = Gold pog.svg

| marksize = 10

| link = Santa Inés Formation

}}

{{Location map~ | South America

| lat_deg = -10.6

| lon_deg = -73.9

| mark = Yellow ffff80 pog.svg

| marksize = 10

| link = Ipururo Formation

}}

Four species have been described in the genus Boreostemma.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=197861 Boreostemma] at Fossilworks.org Unspecified Boreostemma fossils were found in the Ipururo Formation of the department of Ucayali, Amazonian Peru.[https://paleobiodb.org/classic/displayCollResults?collection_no=144792 IN-DTC-28] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=144793 IN-DTC-32] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=163840 IN007] at Fossilworks.org Asterostemma contains the type species A. depressa and several nomina dubia. The genus has been found in the Early Miocene (Santacrucian in the SALMA classification) Santa Cruz Formation of the province of Santa Cruz, Argentina and in the Solimões Formation in the state of Acre, Amazonian Brazil.[https://paleobiodb.org/classic/displayCollResults?collection_no=176567 Cañadón Jack, Yak-Harvey] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=55602 Rio Acre] at Fossilworks.org

;B. pliocena

The type species B. pliocena was described in 2008 by Carlini et al. based on 30 osteoderms palate fragment with M6-7 alveoli.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=197862 Boreostemma pliocena] at Fossilworks.org Fossils have been described from the type locality along the road to Tío Gregorio in the Codore Formation at the Lagerstätte of Urumaco.[https://paleobiodb.org/classic/displayCollResults?collection_no=114473 Road to Tio Gregorio Locality] at Fossilworks.org

;B. gigantea

B. gigantea was described as Asterostemma gigantea in 1997 by Carlini et al. based on a partial skeleton.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=291744 Boreostemma gigantea] at Fossilworks.org Fossils have been recovered at the Duke Localities 32, 108, 113, 114 and 121W in the La Victoria Formation of the Honda Group at the Konzentrat-Lagerstätte La Venta.[https://paleobiodb.org/classic/displayCollResults?collection_no=13686 Duke Locality 32] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=13754 Duke Locality 108] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=13750 Duke Locality 113] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=13757 Duke Locality 114] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=13758 Duke Locality 121W] at Fossilworks.org

;B. acostae

B. acostae was described as Asterostemma acostae in 1983 by Carlos Villarroel based on a carapace fragment with 44 plates.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=271891 Boreostemma acostae] at Fossilworks.org Fossils have been found in the Cerbatana Member, and the Chunchullo Sandstone of the La Victoria Formation, of the Honda Group at the Konzentrat-Lagerstätte La Venta.[https://paleobiodb.org/classic/displayCollResults?collection_no=139894 Arcillas San Nicolas] at Fossilworks.org[https://paleobiodb.org/classic/displayCollResults?collection_no=146527 Chunchullo Sandstone] at Fossilworks.org

;B. venezolensis

B. venezolensis was described as Asterostemma venezolensis in 1947 by George Gaylord Simpson,Simpson, 1947, p.2 based on most of the carapace and the anterior end of the lower jaw, including teeth.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=291743 Boreostemma venezolensis] at Fossilworks.org Fossils have been uncovered from the Santa Inés Formation along the banks of the Güere River in the state of Anzoátegui in Venezuela.[https://paleobiodb.org/classic/displayCollResults?collection_no=145509 Banks of the Güere River] at Fossilworks.org

Gallery

{{left|

File:Boreostemma shield - Colombia.jpg|Carapace of Boreostemma

File:Boreostemma reconstruction - Colombia.jpg|Reconstruction

}}

References

= Bibliography =

{{citation |last1=Carlini |first1=Alfredo A. |last2=Zurita |first2=Alfredo E. |last3=Scillato Yané |first3=Gustavo J. |last4=Sánchez |first4=Rodolfo |last5=Aguilera |first5=Orangel A. |year=2008 |title=New Glyptodont from the Codore Formation (Pliocene), Falcón State, Venezuela, its relationship with the Asterostemma problem and the paleobiogeography of the Glyptodontinae |url=https://www.researchgate.net/publication/226272164 |journal=Paläontologische Zeitschrift |volume=82 |issue=2 |pages=139–152 |doi=10.1007/BF02988405 |bibcode=2008PalZ...82..139C |accessdate=2017-09-26}}
{{citation |last1=González Ruiz |first1=Laureano R. |last2=Ciancio |first2=Martin R. |last3=Martin |first3=Gabriel M. |last4=Zurita |first4=Alfredo E. |year=2014 |title=First record of supernumerary teeth in Glyptodontidae (Mammalia, Xenarthra, Cingulata) |url=http://naturalis.fcnym.unlp.edu.ar/repositorio/_documentos/sipcyt/bfa004906.pdf |journal=Journal of Vertebrate Paleontology |volume=e885033 |issue=1 |pages=1–6 |doi=10.1080/02724634.2014.885033 |bibcode=2015JVPal..35E5033G |accessdate=2017-09-26}}
{{citation |last=González |first=Laureano Raul |year=2010 |title=Los Cingulata (Mammalia, Xenarthra) del Mioceno Temprano y Medio de Patagonia (edades Santacrucense y "Friasense") revisión sistemática y consideraciones bioestratigráficas (PhD thesis) |url=https://www.researchgate.net/publication/271910514 |publisher=Universidad Nacional de La Plata |pages=1–468 |accessdate=2017-09-26}}
{{citation |last=Simpson |first=George Gaylord |year=1947 |title=A Miocene glyptodont from Venezuela |url=http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.866.6506&rep=rep1&type=pdf |journal=American Museum Novitates |issue=1368 |pages=1–10 |citeseerx=10.1.1.866.6506 |accessdate=2018-10-01}}
{{citation |last1=Zurita |first1=Alfredo E. |last2=González Ruiz |first2=Laureano R. |last3=Gómez Cruz |first3=Arley J. |last4=Arenas Mosquera |first4=José E. |year=2013 |title=The most complete known Neogene Glyptodontidae (Mammalia, Xenarthra, Cingulata) from northern South America: taxonomic, paleobiogeographic, and phylogenetic implications |url=https://www.researchgate.net/publication/263555527 |journal=Journal of Vertebrate Paleontology |volume=33 |issue=3 |pages=696–708 |doi=10.1080/02724634.2013.726677 |bibcode=2013JVPal..33..696Z |hdl=11336/2971 |accessdate=2017-09-26|hdl-access=free }}