Crayfish burrows from Late Jurassic-Late Cretaceous continental deposits of Patagonia: Argentina. Their palaeoecological, palaeoclimatic and palaeobiogeographical significance

Authors
Bedatou, Emilio; Melchor, Ricardo Nestor; Bellosi, Eduardo Sergio; Genise, Jorge Fernando
Publication Year
2008
Language
English
Format
article
Status
Published version
Description
The trace fossil, Loloichnus baqueroensis igen. and isp. nov., from Late Jurassic-Late Cretaceous continental deposits of Patagonia, Argentina, includes thickly lined, mostly passively-filled, and Y-branched burrows. Other important features of this ichnofossil are the inner surface texture of lining showing transversal, elongated, and adjacent grooves, and less commonly, the pelletal filling of burrows. L. baqueroensis is recorded from the Bajo Grande, Bajo Tigre, Punta del Barco, and Laguna Palacios Formations, which were deposited in different volcaniclastic environments of the Deseado Massif and San Jorge Basin geological provinces, respectively. The described burrows are found in many levels of palaeosols developed in reworked piroclastic deposits, where they are the main component of the ichnofabrics, in association with meniscate and thinly lined burrows and a diffuse and complex boxwork of small diameter burrows. Root traces are also present, and in many cases, occur inside L. baqueroensis. Considering general morphology, surface texture, filling types, palaeoenvironments in which they occur, and comparisons with extant and fossil decapod burrows, the likely trace makers of L. baqueroensis were crayfishes (Decapoda: Astacidea), probably Parastacidae. The producers of L. baqueroensis inhabited soils, where their burrows probably reached the water table, and contained roots that were used for feeding. Considering climatic preferences of extant parastacids, it is proposed a temperate climate for central Patagonia during the deposition of the studied units. The widespread presence of crayfishes during Late Jurassic-Late Cretaceous times in central Patagonia, supports the monophyletic origin of this group during the Triassic, and suggests that the present restricted geographic distribution in southern South America is a relict of a broader one.
Fil: Bedatou, Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina
Fil: Melchor, Ricardo Nestor. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina
Fil: Bellosi, Eduardo Sergio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina
Fil: Genise, Jorge Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina
Subject
CRAYFISH BURROWS
LATE JURASSIC-LATE CRETACEOUS
PALAEOBIOGEOGRAPHY
PALAEOCLIMATOLOGY
PALAEOECOLOGY
PATAGONIA
Paleontología
Ciencias de la Tierra y relacionadas con el Medio Ambiente
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/81631