The nature of drilling predation, although well documented for molluscan fossils, is understudied for micromolluscs (<5mm). Studying predation in micromolluscs is especially critical in evaluating the adaptive significance of micromorphy against predation and assessing the importance of predator-prey size relationship (PPSR). This study documents drilling predation event in microbivalves from early Miocene (Burdigalian) fossil assemblage of Quilon limestone from Kerala, India. Our sample of ~2000 valves represent nine families with an average drilling frequency (DF) of 0.06 and an incomplete drilling frequency (IDF) of 0.26. The characteristic drillhole morphology and occurrence of five genera of modern drilling gastropods (Naticid: Natica, Tanea and Polinices; Muricid: Triplex and Dermomurex) from the same locality reveals the predator identity. Predation in the studied assemblage is found to be highly selective in terms of prey taxa, size, mobility and site selection. Six out of nine families show evidence of predation indicating taxon selectivity.Poor correlation between DF and abundance further supports this view. Failed attacks are strongly correlated with morphological features such as surface ornamentation (Lucinidae), presence of conchiolin layers (Corbulidae). Drilling occurs primarily on medium size class and prey outside this size range show lower rate of attack. This indicates the existence of an "inverse size refugia" for extremely small prey along with the classical size refugia existing for large prey. Mobility is found to be a deterrent to drilling predation and it also increases failure.Microbenthos of Quilon limestone shows a lower predation intensity in comparison to the Miocene macrobenthos worldwide including coeval formation of the Kutch Basin. The interaction in microbenthos is more strongly size-dependent in contrast to the Kutch fauna.Reduced predation intensity in microfauna and existence of "inverse size refugia" support the .

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&lt;p&gt;Seagrasses are a vital part of the marine ecosystem, owing to their contribution to oceanic primary productivity and supporting highly diverse marine ecosystems. The fossil record of seagrasses is rare because of their poor preservation potential. Sedimentological and taphonomic indicators are generally used to identify the paleo seagrass habitat. The fossil record of seagrass-associated taxa such as foraminifera, corals, bryozoans, molluscs, and sirenians can also provide indirect evidence of this specific habitat. These constitute Indirect Paleo-Seagrass Indicators (IPSIs). The early Miocene (Burdigalian) fossil assemblage of Quilon limestone of Kerala, India, has been interpreted as a seagrass habitat based on the species association of gastropods, bryozoans, and foraminifera. This is the only reported seagrass ecosystem from West Indian Province (WIP). In our study, we attempt to develop a new multi-proxy approach using morphology, ecology, and geochemical signatures of seagrass-associated molluscs from the Quilon Formation and evaluate its potential to reconstruct a paleo-seagrass ecosystem.&lt;/p&gt; &lt;p&gt;Our sample consisted of ~2000 specimens of microbivalves representing nine families of bivalves. We also included previously reported 16 families of macrobivalves in our ecological analysis. The molluscan community of the Quilon Formation is dominated by families that are mobile (67%), infaunal (65%), and suspension feeders (78%) in comparison to other ecological guilds. The seagrass ecosystem, characterized by soft substratum and high suspension load, favors these ecological strategies. The high proportional abundance of Lucinidae bivalves (8.9%) in the assemblage agrees with the expectation of dominance of chemosymbionts in the seagrass meadows. The small body size (&lt;10mm ) and low predation intensity (drilling frequency 0.06, repair scar frequency 0.04) reported from this community also match the expected pattern of a seagrass ecosystem serving as a nursery.&lt;/p&gt; &lt;p&gt;We analyzed molluscan shells from Quilon limestone for stable isotope ratios. We also supplemented this data with published data of present and past seagrass-associated molluscs. Using this data, we evaluated the influence of ecological variables in shaping the stable isotope signature of molluscs in the seagrass ecosystem. The

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