Arthropod interactions with bennettitalean roots in a Triassic permineralized peat from Hopen, Svalbard Archipelago (Arctic)

• Published in: Palaeogeography, Palaeoclimatology, Palaeoecology
• Main Authors: Strullu-Derrien, Christine, Mcloughlin, S., Philippe, M., Mørk, A., Strullu, D.
• Other Authors: Laboratoire de Planétologie et Géodynamique - Angers (LPG-ANGERS), Laboratoire de Planétologie et Géodynamique UMR 6112 (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: Bennettitales; Oribatid mites; Palaeoecology; Plant–arthropod interactions; Silicified flora; Svalbard; Triassic; Wood anatomy; [SDU]Sciences of the Universe [physics]; Hopen; Hopen island
• Online Access: https://univ-angers.hal.science/hal-03278083; https://doi.org/10.1016/j.palaeo.2012.06.006

International audience Multiple thin-sections of a Late Triassic (Carnian) siliceous permineralized peat block likely derived from the De Geerdalen Formation on Hopen Island, Svalbard Archipelago, show a dense mass of roots preserving fine anatomical details of various stages of primary and secondary vascular tissue development. The presence of moderately defined rings with few latewood cells in the secondary xylem attests to growth in a seasonal environment. The presence of mucilage bodies and nests of sclerotic cells in the cortical tissues of the roots and pith of subaerial stem fragments, together with scalariform pitting on radial tracheid walls and 2–12 simple pits per cross-field favor bennettitalean affinities for the roots. Evidence of a rich fauna of detritivores inhabiting the peat profile is represented in the form of extensive damage to cortical tissues of dead roots and abundant coprolites preserved both within chambers excavated in the plant tissues and in the peat matrix. Less common gall-like structures within the roots indicate the presence of parasitic organisms in the palaeo-peat ecosystem.