Insect herbivory on ferns from a midland Atlantic Rainforest locality, southern Brazil: implications for interpreting fossil plant–insect interaction

This work contains the results of fern–arthropod interactions from a midland Atlantic Rainforest locality and addresses the taphonomic, morphological and ecological implications of insect damage on ferns to interpret them on fossil plant assemblages. Six functional feeding groups – margin feeding, hole feeding, surface feeding, piercing and sucking, mining and galling – are present on the three fern species inhabiting the understory of an Araucaria Forest in the Atlantic Forest biome, southern Brazil. We recognised 19 damage types (DTs), including 14 arthropod-induced DTs, three of which are newly proposed herein. Five of the DTs found were first recorded on ferns. Of the DTs found, the proportion of guilds such as mining and galling shows a significant similarity with those of an upland locality. Products of arachnids and insect behaviour on ferns made up 25% of all fern–arthropod interactions in the midland locality, which included dead bodies and byproducts from processes of arthropod life cycle, which are unlikely to be preserved in the fossil record. This rate of arthropod products consists of significant evidence of interactions to unveil deep-time relationships between arthropods and plants. Lastly, leaf damage on living ferns is more frequent than those occurring in fossil plant assemblages.

本数据集包含来自大西洋雨林内陆样点的蕨类-节肢动物相互作用研究结果，旨在探讨昆虫损伤对蕨类植物的埋藏学（taphonomic）、形态学（morphological）及生态学（ecological）意义，以将其应用于化石植物组合的相关解读。本次研究在巴西南部大西洋森林生物群区南洋杉林林下的3种蕨类植物上，发现了6类取食功能群（functional feeding groups）：叶缘取食、蛀孔取食、表面取食、刺吸取食、潜叶取食及虫瘿取食。研究共识别出19种损伤类型（damage types, DTs），其中14种为节肢动物诱导产生，另有3种为本文首次提出；其中5种损伤类型为首次在蕨类植物上记录。在所发现的损伤类型中，潜叶取食、虫瘿取食等功能群的占比，与高地样点的结果存在显著相似性。该内陆样点中，蛛形纲动物（arachnids）与昆虫在蕨类上的行为产物占所有蕨类-节肢动物相互作用记录的25%，此类产物包括节肢动物生命周期过程中产生的尸体及副产物（byproducts），这类产物通常难以保存在化石记录（fossil record）中。这类节肢动物产物的占比，为揭示节肢动物与植物间的深时演化关系（deep-time relationships）提供了重要证据。此外，活体蕨类叶片的损伤频率高于化石植物组合中的损伤频率。