A study on the feeding habits and gnathal appendages in oribatid mites (Acarina: Cryptostigmata)

Abstract

The numerical abundance of oribatid mites makes them the most important quantitative component among the soil mesofauna. Within the soil, they are actively involved in litter decomposition mainly due to their habit of feeding on plant residues (

Isopod mouthpart traits respond to a tropical forest recovery gradient

“…5h), suggesting a diet that contains a high proportion of fungi. These results are similar to those of a comparative study of Oribatid mite mouthpart morphology (Xavier and Haq 2007), which found that fungal feeders (described as "microphytophages") had "elongated and narrow chelicerae with small sharp teeth suitable for nibbling fungal cushions" and less developed rutellae, while species which grazed directly on leaves and wood had chelicerae bearing thicker teeth, and rutellae which were more developed (i.e., larger and more sclerotized) and that contained a concave vestibule that was used to collect scraped food particles for further mastication.…”

“…Morphological mouthpart traits may enable bottom-up predictions of ecosystem functionA key goal of functional trait ecology is to enable the prediction of ecosystem function across different environments using traits, but this goal can only be achieved if appropriate traits (i.e., those which both respond to the environment and have an effect on ecosystem function) are measured. Our ndings reinforce existing studies in suggesting that mouthpart traits measured from the mandibles in isopods(Brousseau et al 2019) and collembolans (Raymond-Léonard et al 2019), and from the chelicerae or rutellae in oribatid mites(Xavier and Haq 2007;Perdomo et al 2012), may qualify as such traits. Our study found that morphological mouthpart traits in detritivorous litter isopods respond to variation among tropical forest plots across an environmental gradient.…”

“…That is, our data suggested that species that are likely fungivorous with narrow, serrated LM tended to have lower biting strength than those that are likely directly detritivorous with broader, less serrated LMs. This covariation in mechanical strength and morphology is also noted by Xavier and Haq (2007) for Oribatid mites, and should be further explored using larger datasets of isopod species.…”

“…Similarly, morphological mouthpart traits, which refer to the dimensions of biting surfaces and sensory organs on invertebrate mouthparts, and are derived from the mechanical advantage generated by mandible shape, have been shown to match the traits of resources being consumed by a variety of detritivorous invertebrates (Brousseau et al 2019;Raymond-Léonard et al 2019). For example, the size of the molar plate on the mandibles of collembolans is well recognized as an indicator of a plant or fungal diet (Malcicka et al 2017), and the size and dentition of oribatid mite chelicerae and rutellae re ect the degree to which species consume fungal or plant material (Xavier and Haq 2007).…”