The pre-Oligocene diversity of hypsodont typotherians (Mammalia, Notoungulata) in northwestern Argentina

GARCÍA LÓPEZ, DANIEL ALFREDO; JAVIER GELFO; SCANFERLA, CARLOS AGUSTÍN; BABOT, JUDITH; FERRO, AGOSTINA; SAADE, LUIS

AMEGHINIANA

ASOCIACION PALEONTOLOGICA ARGENTINA

Lugar: Buenos Aires; Año: 2020 vol. 57 p. 117 - 131

0002-7014

Until the discovery of the genusPunahyrax (Geste Formation) in different localities of Catamarca and Saltaprovinces, ?archaeohyracids? were unknown in northwestern Argentina. Here weanalyze the record of these notoungulates in the region through specimens knownfor the Geste Formation and new remains recovered from the lower levels of theQuebrada de Los Colorados Formation, assessing their diversity and significancein the context of the pre-Deseadan radiation of Typotheria. We identify three ?archaeohyracid?morphotypes for Barrancan levels and four for Mustersan levels in northwesternArgentina, implying the possible presence of as much as seven ?archaeohyracid? taxain the region for the last third of the Eocene, and illustrating a strikingdiversity, especially considering the scarce pre-Tinguirirican record knownuntil now. These new records underline the faunal differences of the Geste andQuebrada de los Colorados formations regarding the highly fossiliferous Lowerand Upper Lumbrera formations. In this sense, although the existence of asample bias should not be completely dismissed, the possibility of importantbiogeographic barriers acting in the area by the late middle Eocene needs to beanalyzed with independent evidence. The record of Pseudhyrax eutrachytheroidesin northwestern Argentina represents the first notoungulate taxón commonbetween this region and typical Patagonian localities and represents a usefuland presumably reliable new basis for the assignment of a Mustersan age for themiddle section of the Geste Formation.<!-- /* Font Definitions */@font-face{font-family:"ＭＳ 明朝";mso-font-charset:78;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1791491579 18 0 131231 0;}@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Cambria;panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073743103 0 0 415 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Cambria;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:"ＭＳ 明朝";mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:JA;}size:595.0pt 842.0pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:35.4pt;mso-footer-margin:35.4pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}<!-- /* Font Definitions */@font-face{font-family:"ＭＳ 明朝";mso-font-charset:78;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1791491579 18 0 131231 0;}@font-face{font-family:"ＭＳ 明朝";mso-font-charset:78;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1791491579 18 0 131231 0;}@font-face{font-family:Cambria;panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073743103 0 0 415 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin:0cm;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Cambria;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:"ＭＳ 明朝";mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-fareast-language:JA;}size:595.0pt 842.0pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:35.4pt;mso-footer-margin:35.4pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}