Effects of emersion on acid–base regulation, osmoregulation, and nitrogen physiology in the semi-terrestrial mangrove crab, Helice formosensis

Shallow-water hydrothermal vent system as an extreme proxy for discovery of microbiome significance in a crustacean holobiont

“…The dissolved inorganic carbon (DIC) content of water samples was analyzed in triplicate using a DIC analyzer (AS-C3, Apollo SciTech, Newark, DE, USA) with nitrogen as an inert gas, followed by quantification via a nondispersive infra-red (NDIR) Li-7000 CO 2 =HCO − 3 analyzer (LI-COR, Lincoln, NE, USA). The hemolymph DIC content was measured following a method described previously (Allen et al, 2021). The HCO − 3 concentration of water samples was calculated according to DIC, pH, and temperature using a CO2SYS module undergone within Microsoft Excel (Pierrot et al, 2006).…”

“…The shallow-water HV plumes cause several physicochemical parameters such as temperature, pH, and redox status to vary over an extreme range of values (Peng et al, 2011;Dahms et al, 2018;Pang et al, 2019;Misuraca et al, 2021). As such, ventassociated biological communities must exhibit adaptive behavioral, physiological, morphological and symbiotic features to sustain their lives (Adams et al, 2011;Hu et al, 2016;Allen et al, 2021). For example, previous reports have detailed unique biochemical mechanisms for sulfide detoxification (Wang et al, 2021), behavioral and molecular responses to high temperatures (Gurunathan et al, 2021), and the presence of specialized transepithelial ionocytes to cope with low-pH conditions (Hu et al, 2016).…”

“…The study showed that the subcellular localization of VHA was mainly within the cytosol and along with the apical membrane of the gill lamella epithelium, supporting the idea that VHA is involved in proton secretion as a mechanism of acid excretion (Hu et al, 2016). Additionally, similarly to vertebrate blood, crab hemolymph serves as a major transport medium for materials between cells and all the internal tissues in the body, such as hormones, waste materials, and nutrients, which have also been well documented (Allen et al, 2020;Allen et al, 2021). In this way, the physiochemical parameters in the hemolymph of crabs can be used to describe the physiological responses and adaptive characteristics.…”

Exercise and emersion in air and recovery in seawater in the green crab (Carcinus maenas): Effects on nitrogenous wastes and branchial chamber fluid chemistry

“…Interestingly, neither urate‐N (Lallier & Walsh, 1990) nor Ca 2+ and Mg 2+ (Booth et al, 1984) were elevated during or after aquatic exercise in the blue crab ( C. sapidus ), though there were substantial elevations in T Amm and ammonia excretion rates (Booth et al, 1984; Milligan et al, 1989). Hemolymph glutamate and glutamine were also measured as these amino acids are often involved in N‐shuttling mechanisms, as discussed by Regnault (1992) and Allen et al (2021). However, in accord with the findings of Allen et al (2021) on emersed Helice formosensis (the semi‐terrestrial thick crab), we found no significant changes in either glutamate or glutamine (Figure 6a–d).…”

Characterization of 3 different types of aquaporins in Carcinus maenas and their potential role in osmoregulation

“…was sampled from the arthrodial membrane of the rear walking leg using an 18-gauge needle whereas urine was aspirated from the deflected nephropore using a pipet after thoroughly drying the crab's anterior region as described by Allen et al (2021). Additional hemolymph and urine samples were collected after 3, 6, 12,18, 24, 48, and 168 hours (7-days) of exposure to brackish conditions (10 ppt.).…”