Evaluation of the Use of Autonomous Reef Monitoring Structures (ARMS) for Describing the Species Diversity of Two Coral Reefs in the Yucatan Peninsula, Mexico

Abstract

Autonomous reef monitoring structures (ARMS) have been proposed as a standardized, passive, nondestructive sampling tool. This study assessed the ability of ARMS to capture the cryptic species diversity of two coral reefs by recording species richness and taxonomic representativeness using conventional taxonomy. The capacity of ARMS, as artificial substrates, to favor the establishment of nonindigenous species over native species was also evaluated. The use of ARMS allowed the detection of 370 species morphotypes from nine phyla, yielding 13 new records of geographic distribution expansion, one exotic species for the Gulf of México and the Caribbean Sea, and six newly described species. It was also possible to make spatial comparisons of species richness between both reefs. ARMS captured cryptic diversity exceptionally well, with the exception of echinoderms. Furthermore, these artificial structures did not hinder the colonization ability of native species; in fact, the colonization patterns on the structures themselves represented the spatial differences in the structure of benthic assemblages. This study represents the first effort to make a conventional taxonomic description of the cryptic fauna of the Yucatan Peninsula using ARMS. It is recommended to assess coral reef species diversity, but more taxonomists specialized in marine invertebrates are needed.

Seq’ and ARMS shall find: DNA (meta)barcoding of Autonomous Reef Monitoring Structures across the tree of life uncovers hidden cryptobiome of tropical urban coral reefs

“…The majority of non‐metazoan eukaryote taxa are small and difficult to sample. ARMS becomes advantageous as it provides an efficient method to collect, study and characterize such communities (Casey et al, 2021; Palomino‐Alvarez et al, 2021; Pearman et al, 2019, 2020). Here, we identified marine fungi Ascomycota, Basidiomycota, and red algae Rhodophyta as the main non‐metazoan eukaryote contributors to a tropical urban reef cryptobiome (Figure 2b; Appendix S1).…”

“…Since ARMS mimics the physical complexity of coral reefs, organisms that are dependent on reef cavities would likely also find ARMS suitable for inhabitation (Palomino‐Alvarez et al, 2021; Pearman et al, 2020; Plaisance et al, 2011; Zimmerman & Martin, 2004). Interestingly, we found that higher coral cover was associated with higher COI metazoan diversity though not with 18S metazoan diversity (Figure 4c), so it is possible that non‐invasive survey methods focused on conspicuous reef organisms have overlooked the “hidden majority” concealed within crevices that could drive these invertebrate richness patterns (Pearman et al, 2018).…”

“…In particular, larger metazoans (i.e., ≥2 mm and BSS sections) were observed to drive spatial patterns here (Figure S1), and this was supported by known contributions of larger‐sized reef‐associates to assemblage dissimilarity among sites (Fraser et al, 2021; Pearman et al, 2018). Macrofauna that are known to depend on reef cavities (Fraser et al, 2021; Nelson et al, 2016) would also find the ARMS suitable for inhabitation because of the structurally complex niches it mimics (Palomino‐Alvarez et al, 2021; Plaisance et al, 2011; Zimmerman & Martin, 2004) and the refugia it provides (Rogers et al, 2018). This suggests that higher coral cover sites may host more unique metazoan communities than lower coral cover sites (Figures 4 and 5).…”

“…The Autonomous Reef Monitoring Structure (ARMS) is a cost‐effective and manpower efficient long‐term sampling device (Leray & Knowlton, 2015) designed to mimic the three‐dimensional coral reef matrix by providing finely‐structured spaces for colonization and settlement of a variety of reef organisms (Zimmerman & Martin, 2004). The recruited cryptobiota can be processed with either morphological (David et al, 2019; Palomino‐Alvarez et al, 2021) and/or molecular tools (Leray & Knowlton, 2015; Ransome et al, 2017). This device is not without limitations, as it might exclude pioneer species or induce colonization trends that are distinct from those on natural substrates (Pearman et al, 2020).…”

Sea slugs (Gastropoda: Heterobranchia) associated with Autonomous Reef Monitoring Structures (ARMS) in southern Gulf of Mexico and Mexican Caribbean Sea

“…hydroids and bryozoans) can also be present. In ARMS, several food sources for heterobranch sea slugs are found, such as sponges, ascidians, bryozoans, hydroids and algae, because the structures are used as a hard substrate base (Palomino-Alvarez et al, 2021a, 2021b, thus increasing the possibility of finding specimens of different feeding habits.…”