The Talacasto Formation is a geological formation in Argentina, exposed primarily across San Juan Province, with an additional outcrop in La Rioja Province. It preserves fossils dating back to the Devonian period.

Talacasto Formation
Stratigraphic range: Devonian
TypeGeological formation
Unit ofGualilán Group
Thickness300–1,000 m (980–3,280 ft)
Location
Region
Country Argentina
ExtentPrecordillera Basin
Type section
Named byPadula et al
Year defined1967

Description

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The Talacasto Formation is exposed in the Precordillera Basin of Argentina, with outcrops most widespread in San Juan Province, though an isolated exposure also exists at Sierra de las Minitas in La Rioja Province.[1][2] Along with the Punta Negra Formation, it makes up the Gualilán Group, which represent Devonian-aged deposits in the Argentine Precordillera.[3] The thickness of the Talacasto Formation varies across its extent; at the type locality of Quebrada de Talacasto in the south it is 300 m (980 ft) thick, while at the Loma de los Piojos section near the Jáchal River in the north it exceeds 1,000 m (3,300 ft) in thickness.[1]

Fossil content

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Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Bivalves

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Bivalves reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Actinopteria[4] A. eschwegei Loma de los Piojos About 20 specimens A pterineid
A. modesta Loma de los Piojos Several specimens A pterineid
Anthracoleda[4] A. (Pseudoleda) minuta
  • Cerro del Fuerte
  • Loma de los Piojos
Several specimens A nuculanid
Deceptrix[4] D. (Devonodeceptrix) jachalensis Loma de los Piojos Several specimens A cardiolariid
Glossites[4] G. cf. G. depressus Loma de los Piojos 2 specimens A modiomorphid
Grammysioidea[4] G. capricornus Loma de los Piojos 5 specimens A grammysiid
Nuculites[4] N. argentinum
  • Cerro del Fuerte
  • Loma de los Piojos
Numerous specimens A cucullellid
Nuculoidea[4] N.? sp. Cerro del Fuerte 4 specimens A nuculid
Palaeoneilo[4] P. cf. P. forbesi Loma de los Piojos 5 internal moulds A malletiid
Pholadella[4] P. radiata Loma de los Piojos 7 specimens A sanguinolitid

Brachiopods

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Brachiopods reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Anoplia[5][6] A. azucenae Portezuelo del Tambolar Over 70 specimens An anopliid
A. sp. A Río Talacasto 6 specimens An anopliid
A. sp. Los Algarrobos section An anopliid
Athyris[6] A. sp. Los Algarrobos section An athyridid
Australostrophia[5] A. penoensis
  • Loma de los Piojos
  • Cerro del Fuerte
  • Agua del Peñón
Numerous specimens A strophochonetid
Boucotia[7] B. argentina
  • Loma de los Piojos
  • Portezuelo del Tambolar
3 isolated valves A notanopliid
Chonostrophia[5][8] C. elenae Loma de los Piojos Several specimens A chonostrophiid
C. reversa var. andina Quebrada de Talacasto Several specimens Tentatively reclassified as a species of Sanjuanetes[9]
Eoschucertella[10] E. delicata Quebrada Zerina Numerous specimens An areostrophiid
Iridistrophia[10] I. aliciae Cerro del Fuerte Numerous specimens A chilidiopsid
I. dominans Loma de los Piojos Numerous specimens A chilidiopsid
I. magna Cordón de Agua de Peñón Numerous specimens A chilidiopsid
I. prima Quebrada La Cortadera Numerous specimens A chilidiopsid
Kentronetes[5] K. giolittii Quebrada Las Loras 6 valves A strophochonetid
K. ortegae Loma de los Piojos Numerous specimens A strophochonetid
K. vallensis Loma de los Piojos 31 specimens A strophochonetid
K. variabilis
  • Portezuelo del Tambolar
  • Poblete Sur
  • Quebrada del río Talacasto
  • Quebrada del Chañar (Cerro La Chilca)
  • Loma de los Piojos
32 valves A strophochonetid
Lingula[6] L. sp. Los Algarrobos section A lingulid
Lomaella[5] L. primoris Loma de los Piojos 9 specimens An eodevonariid
L. sanjuanina Loma de los Piojos Several specimens An eodevonariid
Meristella[6] M. sp. Los Algarrobos section A meristellid
Metaplasia[6] M. baldisi Los Algarrobos section An ambocoeliid
Pleurochonetes[5] ?P. sp. Loma de los Piojos 32 specimens A chonetid
Plicanoplia[5] P. sp. Loma de los Piojos 5 specimens An anopliid
Sanjuanetes[5][6][8] ?S. andina
  • Quebrada de Talacasto
  • Los Algarrobos section
Several specimens A strophochonetid, originally reported as Chonostrophia reversa var. andina[9]

Cephalopods

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Cephalopods reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Bactrites[1] B. gracilis
  • Quebrada de Talacasto
  • Below Keidel's Bed
18 specimens A bactritid
B. sp.
  • Quebrada de Talacasto
  • Sierra de las Minitas
5 specimens A bactritid
Devonobactrites[1] D.? sp. Loma de los Piojos section 2 specimens A bactritid

Corals

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Corals reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Enterolasma[6] E. sp. Cerro del Fuerte section Fragments & complete specimens A horn coral
Favosites[6] F.? sp. Cerro del Fuerte section 1 colony A tabulate coral
Parastriatopora[6][11] P. cf. gigantea Tambolar section 6 small branch fragments A tabulate coral
P. sanjuanina Los Algarrobos section A tabulate coral
P. sp. Los Algarrobos section A tabulate coral

Echinoderms

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Echinoderms reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Argentinaster[12] A. bodenbenderi Jachal Several specimens An ophiurinid brittle star
Crinoidea indet.[6] Indeterminate Los Algarrobos section A crinoid
Furcaster[12] F. separatus Jachal Multiple specimens A protasterid brittle star
Marginix[12] M. yachalensis Jachal Several specimens An encrinasterid brittle star
Promopalaeaster[12] P.? quadriserialis Jachal Several specimens A valvatid starfish

Hyoliths

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Hyoliths reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Hyolithida indet.[6] Indeterminate Los Algarrobos section A hyolithid

Ostracods

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Ostracods reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Aechmina[13] A. sp. Talacasto Creek 6 specimens A member of Podocopa
Amphizona[13] A.? argentinensis
  • Portezuelo del Tambolar
  • Talacasto Creek
  • Poblete Sur
  • Las Tunas
23 specimens A member of Podocopa
Bollia[13] B. talacastensis
  • Talacasto Creek
  • Poblete Sur
20 specimens A member of Podocopa
Keslingiella[13] K. teresae
  • Los Algarrobos
  • Talacasto Creek
  • Poblete Sur
  • La Chilcas
  • Las Tunas
Several specimens A member of Podocopida
Lapazites[13] L. aff. L. trinodis
  • Portezuelo del Tambolar
  • La Cortadera
  • Poblete Sur
  • La Chilca
12 specimens A member of Podocopa
Petrisigmoopsis[13] P.? rotundum
  • Talacasto Creek
  • La Chilca
Several specimens A member of Podocopa
Pircawayra[13][14] P. antiqua
  • Portezuelo del Tambolar
  • La Cortadera Creek
  • La Chilca
  • Las Aguaditas Creek
5 specimens A member of Palaeocopida
P. peregrina Loma de los Piojos Several specimens A member of Palaeocopida
Suinella[13] S. huarpesi
  • Portezuelo del Tambolar
  • Talacasto Creek
  • Poblete Sur
Several specimens A member ofPodocopa
Thlipsurella[13] T. aff. T. putea
  • Los Algarrobos
  • Talacasto Creek
  • Poblete Sur
  • Las Tunas
33 specimens A member of Podocopida
Ulrichia[13] U. sp.
  • Talacasto Creek
  • Poblete Sur
  • La Chilca
7 specimens A member of Podocopa

Sponges

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Sponges reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Talacastospongia[15] T. minima
  • Talacasto section
  • Los Algarrobos
  • Las Aguaditas
13 specimens A glass sponge

Trilobites

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Trilobites reported from the Talacasto Formation
Genus Species Presence Material Notes Images
Aguaditaspis[16] A. mediaspina
  • Quebrada de las Aguaditas
  • Sierra de las Minitas
Several specimens A dalmanitid
Bainella[17] B. cooperi Cerro La Chilca 6 specimens A calmoniid
B. sanjuanina Cerro La Chilca 8 specimens A calmoniid
Calmonia[17] C. nov. sp. A Loma de los Piojos An internal mould (CORD PZ 8613) A calmoniid
Dalmanitoides[18] D. boehmi Loma de los Piojos Several specimens A dalmanitid
D. drevermanni
  • Loma de los Piojos
  • Cerro La Chilca
Several specimens A dalmanitid
Dalmanitidae indet.[6][16] Gen. et. sp. nov. Quebrada de las Aguaditas One specimen (CEGH-UNC 27422) An unnamed dalmanitid
Indeterminate Los Algarrobos section A dalmanitid
Dalmanitinae gen. et. sp. indet.[2] Indeterminate Sierra de las Minitas Fragmentary pygidium (PULR-132 A-B) A dalmanitid
Deltacephalaspis[17] D. sp. Cerro La Chilca 2 specimens A calmoniid
Echidnops[2][19] E. taphomimus
  • Quebrada de Las Aguaditas
  • Sierra de Los Blaquitos
  • Sierra de las Minitas
12 specimens A phacopid, originally reported as an unnamed species of Paciphacops
Ivanites[16] I. leonorae
  • Quebrada de Las Aguaditas
  • Quebrada de Talacasto
  • Loma de los Piojos
Several specimens A dalmanitid
Maurotarion[6][20][21] M. (Malvinotarion) gaucho Loma de los Piojos 10 specimens An aulacopleurid
M. (Malvinotarion) haudei Loma de los Piojos 2 specimens An aulacopleurid
M. (Malvinotarion) talacastoense La Cantera point 5 specimens An aulacopleurid
M. (Malvinotarion) sp. Portezuelo del Tambolar One specimen (CEGH-UNC 7.086) An aulacopleurid
M. (Malvinotarion) sp. B Cerro La Chilca One specimen An aulacopleurid
M. megacephalum Loma de los Piojos 23 specimens An aulacopleurid
M. sp. Los Algarrobos section An aulacopleurid
Paciphacops[2][6] P. (Paciphacops) sp. Sierra de las Minitas Several specimens Now known as Echidnops taphomimus[19]
P. sp. Los Algarrobos section A phacopid
P.? sp. Sierra de las Minitas One specimen (PULR-127 A-B) A phacopid
Parabouleia[6][22] P. eldredgei Quebrada de Talacasto 9 specimens A calmoniid
P. sp. Los Algarrobos section A calmoniid
Talacastops[2][22] T. zarelae
  • Quebrada de Las Aguaditas
  • Sierra de las Minitas
Multiple specimens A calmoniid
Tarijactinoides[17] T. jarcasensis
  • Cerro La Chilca
  • Loma de los Piojos
13 specimens A calmoniid
Tormesiscus[2] T. cf. hildae Sierra de las Minitas Partial specimen (PULR-130) A calmoniid
Unguliproetus[2] U.? sp. Sierra de las Minitas Two associated fragments A proetid

References

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  1. ^ a b c d Cichowolski, Marcela; Rustán, Juan J. (April 2017). "First report of Devonian bactritids (Cephalopoda) from South America: paleobiogeographic and biostratigraphic implications". Journal of Paleontology. 91 (3): 417–433. doi:10.1017/jpa.2017.17. hdl:11336/183599. ISSN 0022-3360.
  2. ^ a b c d e f g Rustán, Juan J.; Vaccari, N. Emilio; Astini, Ricardo A. (June 2011). "Early Devonian Trilobites from the Sierra De Las Minitas, Northernmost Precordillera (La Rioja Province), Argentina". Ameghiniana. 48 (2): 226–241. doi:10.5710/AMGH.v48i1(335). hdl:11336/53580. ISSN 0002-7014.
  3. ^ García Muro, Victoria J.; Rubinstein, Claudia V.; Rustán, Juan J.; Steemans, Philippe (2018-10-01). "Palynomorphs from the Devonian Talacasto and Punta Negra Formations, Argentinean Precordillera: New biostratigraphic approach". Journal of South American Earth Sciences. 86: 110–126. doi:10.1016/j.jsames.2018.06.009. hdl:11336/87283. ISSN 0895-9811.
  4. ^ a b c d e f g h i Sanchez, Teresa M.; Waisfeld, Beatriz G.; Toro, Blanca A. (1995). "Silurian and Devonian Molluscan Bivalves from Precordillera Region, Western Argentina". Journal of Paleontology. 69 (5): 869–886. ISSN 0022-3360.
  5. ^ a b c d e f g h Herrera, Zarela A. (1995). "The Lower Devonian chonetoidean brachiopods from the Argentine Precordillera". Travaux et Documents des Laboratoires de Géologie de Lyon. 136 (1): 101–147.
  6. ^ a b c d e f g h i j k l m n o Carrera, Marcelo G.; Montoya, Ezequiel; Rustán, Juan J.; Halpern, Karen (2013). "Silurian-Devonian coral associations across a sequence stratigraphic boundary in the Argentine Precordillera". Geological Journal. 48 (2–3): 256–269. doi:10.1002/gj.1332. hdl:11336/24993. ISSN 1099-1034.
  7. ^ Herrera, Zarela Angélica (1995-01-01). "The first notanopliid brachiopod from the South American Devonian sequence". Geobios. 28 (3): 337–342. doi:10.1016/S0016-6995(95)80008-5. ISSN 0016-6995.
  8. ^ a b Levy, Regina; Nullo, Francisco E. (1972). "Chonetidae Devónicos de Argentina. 1. Chonostrophia". Ameghiniana. 9 (2): 138–144.
  9. ^ a b Racheboeuf, Patrick R.; Herrera, Zarela (1994-09-01). "On some new Malvinokaffric Silurian and Devonian chonetacean brachiopods, and reclassification of others". Neues Jahrbuch für Geologie und Paläontologie - Monatshefte. 1994 (9): 541–560. doi:10.1127/njgpm/1994/1994/541. ISSN 0028-3630.
  10. ^ a b Herrera, Zarela Angelica; Salas, María José; Giolitti, Javier A. (January 1998). "Chilidiopsoidea (Brachiopoda) del Devónico Inferior de la Precordillera Argentina". Spanish Journal of Palaeontology (in Spanish). 13 (2): 149–166. doi:10.7203/sjp.24049. ISSN 2660-9568.
  11. ^ García-López, Susana; Fernández Martínez, Esperanza (1995-01-01). "The genus Parastriatopora Sokolov, 1949 (Tabulata) in the Lower Devonian of Argentina: Palaeobiogeographic implications". Geobios. 28 (2): 175–183. doi:10.1016/S0016-6995(95)80223-1. ISSN 0016-6995.
  12. ^ a b c d Martínez, Sergio; Río, Claudia del (2015). "Fossil Asterozoa (Echinodermata) of Argentina". Revista de Biología Tropical. 63 (2): 1–6. doi:10.15517/rbt.v63i2.23123.
  13. ^ a b c d e f g h i j Salas, María José (October 2016). "New Insights on Earliest Devonian (Lochkovian) Ostracods from the Argentine Precordillera". Ameghiniana. 53 (5): 565–585. doi:10.5710/AMGH.04.07.2016.2967. ISSN 0002-7014.
  14. ^ Salas, María J.; Rustán, Juan J.; Sterren, Andrea F. (2013-08-01). "Lower and Middle Devonian Malvinokaffric ostracods from the Precordillera Basin of San Juan, Argentina". Journal of South American Earth Sciences. 45: 56–68. doi:10.1016/j.jsames.2013.02.002. hdl:11336/24991. ISSN 0895-9811.
  15. ^ Carrera, Marcelo G.; Rustán, Juan José (November 2015). "The new genus Talacastospongia: insights on the first record of a Devonian sponge from South America". Journal of Paleontology. 89 (6): 912–919. doi:10.1017/jpa.2016.9. hdl:11336/43851. ISSN 0022-3360.
  16. ^ a b c Randolfe, Enrique A.; RustáN, Juan José; Bignon, Arnaud (2022-01-12). "New dalmanitid trilobite taxa from the Lower Devonian of Argentina: comments on spinosity in endemic taxa from southern high paleolatitudes". Comptes Rendus Palevol (2). doi:10.5852/cr-palevol2022v21a2. ISSN 1777-571X.
  17. ^ a b c d Vaccari, Norberto E.; Waisfeld, Beatriz G.; Edgecombe, Gregory D. (1994-01-01). "Calmoniid Trilobites of the Lower Devonian Scaphiocoelia zone in the Argentine Precordillera". Geobios. 27 (5): 591–608. doi:10.1016/S0016-6995(94)80257-2. ISSN 0016-6995.
  18. ^ Rustán, Juan José; Vaccari, N. Emilio (February 2012). "A revision of the Devonian Malvinokaffric dalmanitid trilobite Dalmanitoides Delo, 1935, on the basis of new data from Argentina". Palaeontologia Electronica. 15 (1): 1–21. doi:10.26879/276.
  19. ^ a b Rustán, Juan José; Balseiro, Diego (November 2016). "The phacopid trilobite Echidnops taphomimus n. sp. from the Lower Devonian of Argentina: insights into infaunal molting, eye architecture and geographic distribution". Journal of Paleontology. 90 (6): 1100–1111. doi:10.1017/jpa.2016.108. hdl:11336/44268. ISSN 0022-3360.
  20. ^ Rustán, Juan J.; Vaccari, N. Emilio (2010). "The Aulacopleurid Trilobite Maurotarion Alberti, 1969, in the Silurian-Devonian of Argentina: Systematic, Phylogenetic and Paleobiogeographic Significance". Journal of Paleontology. 84 (6): 1082–1098. ISSN 0022-3360. JSTOR 40925985. S2CID 129791708.
  21. ^ Rustán, J.; Vaccari, N. (2012-08-01). "The trilobite Maurotarion megacephalum sp. nov. (Aulacopleuridae) in the Lower Devonian of Argentina: phylogenetic and paleobiogeographic remarks". Revista Mexicana De Ciencias Geologicas. 29: 346–354. S2CID 55274075.
  22. ^ a b Edgecombe, Gregory D.; Vaccari, Norberto E.; Waisfeld, Beatriz G. (July 1994). "Lower Devonian calmoniid trilobites from the Argentine Precordillera: new taxa of the Bouleia Group, and remarks on the tempo of calmoniid radiation". Geological Magazine. 131 (4): 449–464. doi:10.1017/S0016756800012097. ISSN 1469-5081.