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Abstract This study was conducted to verify the essentiality of dietary cholesterol for early juvenile slipper lobster, Thenus australiensis (initial weight 4.50 ± 0.72 g, mean ± SD, CV = 0.16), and to explore the potential for interactions between dietary cholesterol and phospholipid. An 8-week experiment was conducted using six experimental feeds containing three supplemental cholesterol concentrations (0, 0.2 and 0.4% dry matter) at two supplemental phospholipid concentrations (0% and 1.0% dry matter). Dietary cholesterol concentrations of ≥ 0.2% resulted in up to threefold greater weight gain compared to 0% dietary cholesterol, but without any significant main or interactive dietary phospholipid effect. An interaction was observed for lobster survival with lowest survival (46%) recorded for combined 0% cholesterol and 0% phospholipid compared to every other treatment (71–100%). However, all surviving lobsters at 0% dietary cholesterol, regardless of dietary phospholipid level, were in poor nutritional condition. Apparent feed intake (AFI) was significantly higher at dietary cholesterol ≥ 0.2% but was lower for each corresponding dietary cholesterol level at 1% dietary phospholipid. This implied that the feed conversion ratio was improved with supplemental phospholipid. In conclusion, this study confirms the essential nature of dietary cholesterol and that dietary phospholipid can provide additional benefits.

Understanding population connectivity helps inform resource and conservation managers about appropriate boundaries for management units. However, for many species facing recent increases in fishing or environmental pressure, accurate information on population structure is lacking. Reef Bugs (Thenus australiensis), commonly known as Moreton Bay Bugs, are iconic shovel-nosed lobsters in northern Australia and an increasingly important fisheries resource. Around 80% of landings occur in the Queensland East Coast Otter Trawl Fishery (ECOTF) where the first stock assessment of the species is underway. However, knowledge about population structure to inform stock assessment is lacking. We used genome complexity reduction-based sequencing to characterise high-quality Single Nucleotide Polymorphisms (SNPs) used to evaluate population structure among three management zones of the ECOTF. Post-filtering, a total of 3,031 SNPs were used to infer no genetic differences among locations indicating strong genetic population connectivity. The presence of a single panmictic population was further supported by cluster and kinship analyses. Broad-scale genetic connectivity likely results from pelagic larval dispersal due to limited adult movements. Findings of high gene flow among connected populations indicate a single biological stock of T. australiensis on Australia's east coast and will inform future fisheries management initiatives. [ABSTRACT FROM AUTHOR]

In Mexico, the spiny lobster fishery is well established but this is not the case with the slipper lobster fishery. For a sustainable fishery, many biological traits must be known, one of which is growth. The objective of the present study was to probe the multi-model approach to identify the curve that best describes the growth of Evibacus princeps from the Gulf of California. Specimens were collected aboard commercial trawlers during the industrial shrimp fishing season (October 2021-March 2022) at depths ranging from 10 to 55 m. Five versions of the Schnute model (including the Von Bertalanffy model) were applied and the best model was selected using the Bayesian information criterion. The estimation of an average model was performed because no model obtained 90% of the evidence. E. princeps from the Gulf of California exhibit an indeterminate growth pattern. [ABSTRACT FROM AUTHOR]

Chelarctus Holthuis, 2002 is widely distributed throughout the Indo-West Pacific, but its biogeographic patterns are unknown because Southern Hemisphere areas, such as the Coral Sea, remained poorly explored. Recent cruises organized by the Muséum national d'Histoire naturelle of Paris and the Australian Institute of Marine Science allowed the molecular identification of Crenarctus crenatus (Whitelegge, 1900), Chelarctus aureus (Holthuis, 1963) and Chelarctus crosnieri Holthuis, 2002 phyllosomae. The Coral Sea C. crenatus larvae are identical to stages IX and X of Scyllarus sp. Z, described in detail by Webber and Booth (2001). Descriptions of phyllosoma stages VI, IX and X of Ch. aureus and stages IX and X of Ch. crosnieri are also presented here. Morphological differences between Crenarctus and Chelarctus larvae are established for the first time and previous misidentifications in the literature are re-assessed.

Chelarctus Holthuis, 2002 is widely distributed throughout the Indo-West Pacific, but its biogeographic patterns are unknown because Southern Hemisphere areas, such as the Coral Sea, remained poorly explored. Recent cruises organized by the Muséum national d'Histoire naturelle of Paris and the Australian Institute of Marine Science allowed the molecular identification of Crenarctus crenatus (Whitelegge, 1900), Chelarctus aureus (Holthuis, 1963) and Chelarctus crosnieri Holthuis, 2002 phyllosomae. The Coral Sea C. crenatus larvae are identical to stages IX and X of Scyllarus sp. Z, described in detail by Webber and Booth (2001). Descriptions of phyllosoma stages VI, IX and X of Ch. aureus and stages IX and X of Ch. crosnieri are also presented here. Morphological differences between Crenarctus and Chelarctus larvae are established for the first time and previous misidentifications in the literature are re-assessed. [ABSTRACT FROM AUTHOR]

The light characteristics of an ecosystem drive evolutionary adaptations in visual traits, enhancing the diversity and abundance of species living there. The visual systems of crustaceans are highly diverse and often correspond to the optical properties of their preferred environments. Although habitat depth is known to greatly influence visual specialization in marine crustaceans, it remains unclear whether depth drives visual adaptions in nocturnal species. Slipper lobsters (Scyllaridae) are nocturnal benthic marine crustaceans distributed throughout a wide range of depths. In order to understand the visual adaptive capabilities of slipper lobsters inhabiting different depths, we characterized the eye structures of a shallow-water species (Parribacus japonicas), an intermediate-depth species (Scyllarides squammosus) and a deep-water species (Ibacus novemdentatus). Moreover, we measured by electroretinogram (ERG) the spectral sensitivities and temporal resolutions for each species using the following light stimuli: UV (λmax 386 nm), blue (λmax 462 nm), green (λmax 518 nm), yellow (λmax 590 nm), and red (λmax 632 nm). Our histological experiments show that all three species possess a typical superposition compound eye with square facets, and their ERG measurements revealed a single sensitivity peak for each species. Notably, peak spectral sensitivity corresponded to habitat depth, with the estimated peak for I. novemdentatus (493.0 ± 9.8 nm) being similar to that of S. squammosus (517.4 ± 2.1 nm), but lower than that of P. japonicus (537.5 ± 9.9 nm). Additionally, the absolute sensitivities at respective peak wavelengths for I. novemdentatus and P. japonicus were higher than that of S. squammosus. No differences were observed among the three species for maximum critical flicker fusion frequency (CFFmax) across light stimuli. However, P. japonicus had lower CFFmax values than the other two species. These data suggest that all three nocturnal slipper lobsters are likely monochromatic and well adapted to dim light environments. Significantly, the deep-water slipper lobster displayed higher spectral sensitivities at shorter wavelengths than the shallow water species, but temporal resolution was not compromised.

The slipper lobster Scyllarus arctus is an important fishery resource in Galicia (NW Iberian Peninsula), with a large reduction of its populations in recent decades in the North-east Atlantic and Mediterranean, but only limited information on its reproduction. This study provides an analysis of the reproductive potential of this scyllarid during two breeding cycles (2008 and 2009) in the NE Atlantic (43°20′N 8°50′W). We studied several reproductive traits (fecundity, brood weight, egg weight and volume) in broods with eggs both in an early and late embryonic stage, in relation to female size and temporal variations. Total output (fecundity and weight) and egg weight were closely linked to maternal size, and this relationship remained in broods with late-stage eggs. In relation to temporal variations, our data revealed an important seasonal variability in fecundity and egg weight, showing an inverse pattern in the reproductive strategy in the first two seasons of the reproductive period, with a maximum egg weight in winter (December–February) and a maximum number of eggs produced in spring (April–May). A predictive model for realized fecundity was developed: log (FE) = 0.064 + 2.907 log (length)−0.018 Month2 + 0.174 Month, which accounted for over 90% of variation in the total data. [ABSTRACT FROM AUTHOR]

The technique of underwater acoustic localization (UAL) is widely used to track submerged targets. In the present study, we consider UAL in the specific application of locating the Mediterranean slipper lobster, Scyllarides latus (S. latus), for the aim of continuous and long-term investigation of its movement patterns. Since visual inspections only offer a snapshot to the life of these nocturnal crustaceans, we used underwater acoustic tags and deployed the first testbed to track a community of S. latus through UAL. The testbed included 19 acoustically tagged S. latus, as well as a sensor network of four receivers that record the time-of-arrival of detected tag's emissions. The testbed operated for six months, and the data collected were analyzed offline. In this paper, we describe the design details of our testbed. We discuss the considerations in choosing both the type of acoustic tags and the structure of the testbed. We also present our algorithm to time synchronize the receivers, and the localization procedure. Our preliminary results show that, for this long-term deployment, the widely used model of clock offset for the receivers is too simplified, and that time synchronization must consider also the clock's skew. We also show that the tagged lobsters are mostly detected by fewer than three receivers, thereby making localization using traditional trilateration methods highly challenging. Finally, preliminary results for the localization of the tagged lobsters in the deployment area are presented. [ABSTRACT FROM AUTHOR]

Two species of slipper lobster, Thenus indicus Leach, 1815, and Scyllarides haanii De Haan, 1841, are reported for the first time from the coastal waters of South of Java, part of the Indian Ocean. A total of two specimens, one specimen of T. indicus from Palabuhanratu Bay and one specimen of S. haanii from Yogyakarta coastal waters, were collected in April and September 2015, respectively. Descriptions and illustrations of the morphological characteristics of the two species and their habitat are presented.

The slipper lobster Scyllarides delfosi is an important resource captured by fishery fleets of red lobster (Panulirus argus westonii) in northern Brazil. Despite the economic potential of this species, information on its biological and fishery aspects is still nonexistent. This study was conducted using four-year data on slipper lobster (2001 and 2003, 2013 and 2014) to analyse population structure and estimate fecundity and egg size of S. delfosi. A total of 547 slipper lobsters, S. delfosi, were collected. Ovigerous females and individuals of all size classes were captured by the fleet, mostly individuals newly recruited to the adult stock. These lobsters showed a 7-mm decrease in total mean length over a period of 10 years. Fecundity ranged from 24,710 to 190,060 eggs and egg diameter ranged from 0.60 to 0.64 mm. Research on life cycle, reproduction, and growth of S. delfosi is essential to provide support for the sustainable exploitation of this species, which is considered by-catch on the northern Brazilian coast, and as such, has no adequate public policies regarding its management. [ABSTRACT FROM AUTHOR]

Two species of slipper lobster, Thenus indicus Leach, 1815, and Scyllarides haanii De Haan, 1841, are reported for the first time from the coastal waters of South of Java, part of the Indian Ocean. A total of two specimens, one specimen of T. indicus from Palabuhanratu Bay and one specimen of S. haanii from Yogyakarta coastal waters, were collected in April and September 2015, respectively. Descriptions and illustrations of the morphological characteristics of the two species and their habitat are presented. [ABSTRACT FROM AUTHOR]

Early reports on larval distributions are frustratingly obscure due to ambiguous identification of plankton samples. A particularly striking case is posed by the so-called 'giant phyllosoma' which attain 80 mm in total length and are among the largest larvaeknowninmarine invertebrates. Basedonthe suppositionthatthese giant larvae are producedbylocal species, Philip Robertson (1968) assigned them to Parribacus. In the present study, 12 phyllosoma larvae collected in the Coral Sea and corresponding to intermediate stages VI to IX are described in detail. The identity of these freshly caught specimens was confirmed as belonging to Parribacus antarcticus (Lund, 1793) by using DNA barcoding methods. This new collection further allowed us to complete the larval series for the genus. The intermediate stage VI, which was missing in previous accounts, is described here for the first time. Besides the Coral Sea larvae, another five phyllosoma specimens previously depositedinUKand German museum collections are also described. Given that nouseful DNA couldbeobtained from the old collection specimens, these larvae were identified as Parribacus sp. based on morphology only. Furthermore, a complete morphometric analysis of Parribacus larvae was undertaken including information from literature dating back to 1830. The first detailed description of all dactyli from a complete phyllosoma of the genus Parribacus is presented, with further comparison with those from other genera of Scyllaridae. [ABSTRACT FROM AUTHOR]

Abstract: The complete larval development of a slipper lobster, Ibacus novemdentatus, from newly hatched phyllosomas to juveniles fed only jellyfish, was successfully achieved. Most larvae passed through 6 phyllosomal and 1 nisto stages. The phyllosomal duration was shorter than that reported in previous studies; notably the 7th larval stage was skipped. This is the first report on the complete phyllosomal development with jellyfish as the sole food source. Moreover, the phyllosomas were reared under either closed recirculating or static conditions, where the shortest duration of phyllosomas was 44 and 41days, respectively. Finally, 12.5% of phyllosomas in recirculating condition and 36.1% in static condition metamorphosed into nistos. We conclude that phyllosomas of I. novemdentatus could metamorphose into nisto in a labor-saving closed recirculating system furnished with ultraviolet sterilization and foam fractionation. The results indicate that mass production of phyllosomas in I. novemdentatus, reared solely on jellyfish in recirculating system, is feasible. [Copyright &y& Elsevier]

Advanced stages of Scyllarus phyllosoma larvae were collected by demersal trawling during fishery research surveys in the western Mediterranean Sea in 2003–2005. Nucleotide sequence analysis of the mitochondrial 16S rDNA gene allowed the final-stage phyllosoma of Scyllarus arctus to be identified among these larvae. Its morphology is described and illustrated. This constitutes the second complete description of a Scyllaridae phyllosoma with its specific identity being validated by molecular techniques (the first was S. pygmaeus). These results also solved a long lasting taxonomic anomaly of several species assigned to the ancient genus Phyllosoma Leach, 1814. Detailed examination indicated that the final-stage phyllosoma of S. arctus shows closer affinities with the American scyllarid Scyllarus depressus or with the Australian Scyllarus sp. b (sensu Phillips et al., 1981) than to its sympatric species S. pygmaeus. [ABSTRACT FROM PUBLISHER]

The reproductive biology of Scyllarides deceptor was studied along the southern Brazilian coast (27°S 48°W) from December 2002 to December 2003. Samples were collected monthly at Xavier Island, where animals were caught and marked. Fecundity and egg size were estimated from ovigerous females caught also in two adjacent islands, Arvoredo and Aranhas. A total of 98 females was recorded at Xavier Island during the sampling period, 24 of these were recaptured and presented time-at-liberty ranging from 14 to 297 days. Ovigerous females were observed during spring and summer, with the moulting period lasting from late winter to spring. Size at sexual maturity was assessed from 66 females caught during the breeding season and estimated in 85.33 mm of carapace length (CL). Mean fecundity of S. deceptor was estimated in 191,262 eggs (±17,811, SE) for females, on average, 94.74 mm long (±1.86 mm SE) (CL). Fecundity was significantly related to CL (R2 = 0.90) Mean egg size was 0.67 mm (±0.005 mm SE) and did not correlate significantly to CL (P = 0.78). The rocky bottom of Xavier Island was favourable for reproduction, presenting shelter and foraging grounds for the ovigerous females. For management purposes, our results suggest the closure of the S. deceptor fishery from November to January and the capture-size of females to be restricted to animals larger than 90 mm (CL). [ABSTRACT FROM PUBLISHER]

Lateral flagella of the antennules of scyllarid lobsters were examined for setal morphology and distribution via scanning electron microscopy. Setal distribution patterns were mapped directly for 3 regions of the antennule (base, tuft, and tip) and analyzed for differences: (1) between left and right antennules, (2) between males and females within a species, and (3) among species by comparing counts of setae per annulus in the ventral tuft region only. Six types of antennular setae were identified based on their external morphology: aesthetascs, simple, modified simple, asymmetric, hemi-plumose, and toothbrush setae. These different types were organized in a clear pattern over the ventral and dorsal surfaces of the lateral flagella of the antennule. Aesthetasc, asymmetric, modified simple, and hemi-plumose setae were found only on annuli in the tuft region between the distal and proximal ends of the flagellum. Simple setae were found on all annuli of all regions of the antennule, and toothbrush setae were mainly concentrated on all annuli of the base region and on proximal annuli of the tuft region. All species of scyllarids examined had the same general pattern of setal distribution and no differences were found between left and right, or male and female antennules. Similar setae located on the lateral antennules of species from the families Nephrophidae and Palinuridae (clawed and spiny lobsters) have been previously described as chemo- and/or mechanoreceptive for use in distance chemoreception (i.e., detection and orientation to olfactory stimuli). Based on work on clawed and spiny lobsters, we predict that the aesthetascs on slipper lobsters have a chemoreceptive function and that simple and toothbrush setae may have a bimodal chemo- and mechanoreceptive function. [ABSTRACT FROM AUTHOR]

Phospholipids, especially phosphatidylcholine (PC), are considered essential nutrients for larval and juvenile stages of many decapod crustacean species due to low rates of endogenous biosynthesis and potential nutritional benefits in assisting lipid digestion and transport. This study was conducted to test the hypothesis that dietary PC is essential and would subsequently have beneficial effects on lipid utilisation and digestibility of fish oil triacylglycerol (TAG) in the slipper lobster, Thenus australiensis. Juvenile slipper lobsters were supplied six formulated experimental feeds with actual PC contents of 0.05, 0.48, 0.65, 0.98, 1.15 and 1.43% (dry matter) for 12 weeks. Manipulating dietary PC content had no effects on survival, growth, chemical composition, whole body or tissue lipid distribution, or apparent digestibility (AD) of gross energy (GE), total lipid (TL) or PC. Juvenile slipper lobsters appeared to possess fully developed and efficient mechanisms for GE, TAG and PC digestion (>95% AD). In vivo lipid class mass balance calculations demonstrated net intake of TL and TAG was considerably greater than was accumulated in the whole-body during growth. Thus, a significant proportion of dietary TL and TAG was utilised for energy and other metabolic processes. In contrast, particularly for low PL dietary treatments (≤ 0.5%), net gain of PC was greater than net intake, indicating a reliance on biosynthesis of PC. Thus, it is concluded that there is no or a very low requirement for dietary PC and thus may not be essential for the examined size class of juvenile T. australiensis when supplied adequate dietary PC biosynthetic precursors and other potentially related dietary nutrients. Further targeted research is recommended to verify if these findings are applicable to larval and early juvenile stages, and to enhance overall understanding of lipid nutritional requirements for T. australiensis. • First detailed lipid nutrition study of juvenile slipper lobster, Thenus australiensis. • Dietary phosphatidylcholine had no effect on growth performance and lipid partitioning. • Efficient baseline digestion and absorption of dietary triacylglycerol and phospholipid. • Evidence of phosphatidylcholine biosynthesis from precursors at rates not limiting to growth. • Low requirement for dietary phosphatidylcholine in context of other nutrients and life stage. [ABSTRACT FROM AUTHOR]

Several surplus production-based bioeconomic models are applied to the Northwestern Hawaiian Islands (NWHI) commercial lobster fishery. The model which best explains the biological dynamics of the fishery is a modification of the Fox model developed by the authors. Economic costs are applied within a number of conceptual frameworks to develop the first integrated bioeconomic model of the fishery. In another development, the opportunity cost of labor based on crew share at the open access equilibrium level of fishing effort is used instead of proxy wage levels. Given the costs incurred, the fishery appears to be self-regulating in terms of long-term fishing effort for maximum sustainable yield. [ABSTRACT FROM AUTHOR]

Morphological descriptions of phyllosoma larvae are essential for correct species identification and investigating the spatiotemporal distribution and recruitment process of spiny and slipper lobsters. Species identification of the phyllosoma larvae in the Scyllarinae subfamily is particularly difficult because of the morphological similarities among species and the scarcity of morphological information describing correct species identity. We extracted mid-to final-stage (V to VIII) phyllosoma larvae ( n = 12) belonging to the subfamily Scyllarinae from several plankton samples collected in the Pacific and then performed molecular species identification using mitochondrial DNA COI and 16S rDNA sequence analyses. Three larvae collected around the Ryukyu Archipelago were identified as Chelarctus aureus (stage VI to VIII), and four collected around the Ryukyu Archipelago and Ogasawara Islands were identified as C. virgosus (V to VIII). One larva (V) collected in the central South Pacific was determined to be a subspecies of C. crosnieri . DNA barcodes could not be made for the remaining four larvae (V to VIII) collected around the Ryukyu Archipelago (designated by ? Chelarctus sp-1). Based on the morphological characteristics of the C. virgosus phyllosoma described in this study and the adult distributions reported to date, C. cultrifer phyllosomas previously reported in Japanese and Taiwanese waters are likely to be C. virgosus . This paper also presents a set of diagnostic morphological characteristics that can be used to discriminate among these four species of Chelarctus and from other genera in the subfamily Scyllarinae.

Following recent advances in hatchery technology and large-scale larval rearing of spiny and slipper lobsters, a greater understanding of key nutritional requirements is now imperative to facilitate feed development for juvenile culture. However, there is a lack of relevant information available for the slipper lobsters, particularly Thenus species. This study sought to evaluate the potential requirements for and effects of a fresh ingredient component in a formulated feed on the growth performance of hatchery-reared juvenile Thenus australiensis. This was assessed using six formulated experimental feeds incorporating fresh blue mussel flesh (BM; Mytilus galloprovincialis) in a geometric series (0, 1.6, 3.1, 6.3, 12.5 and 25.0% dry matter) administered continuously over 9 weeks. An additional dietary treatment of blue mussel half shells (BMHS) was included as a reference feed to establish a benchmark of growth potential. Survival and moult frequency were unaffected by feed treatment. Lobsters fed BMHS displayed a clustered or synchronised moulting pattern with two major moulting events lasting several days each during the experiment. In contrast, lobsters provided experimental feeds moulted continuously throughout the experiment. The BMHS produced approximately 2-fold greater growth compared to experimental feeds, while BM incorporated into experimental feeds had no beneficial effect on growth at any inclusion level. Growth mirrored feed intake where it was also found that feed intake on a dry matter basis was approximately 2-fold higher for BMHS compared to experimental feeds, while biological feed conversion ratios were similar for all feeds. Thus, dry matter intake appeared to be primarily responsible for the difference in growth rates achieved. Bulk chemical analysis revealed that BMHS-fed lobsters had significantly lower ash content coupled with higher gross energy, total lipid and polar lipid contents on a proportional basis compared to lobsters fed formulated experimental feeds. Lobster haemolymph Brix values were also significantly higher in the BMHS treatment lobsters. Higher Brix coupled with decreasing feed intake suggests these lobsters were on average at a more advanced stage within the moult cycle and offers a possible explanation for differences in body chemistry. In conclusion, while growth rates were lower in animals fed formulated feeds compared to benchmark growth performance, overall survival, moulting and growth performance revealed the potential of the basal experimental feed formulation as a reference for future nutrition research with this species without a requirement for inclusion of fresh BM. The research highlights that significant opportunities exist to improve slipper lobster growth performance through maximising feed intake. • First detailed growth and feed evaluation investigation of hatchery-reared juvenile slipper lobster • Superior (2-fold) growth and more synchronous moulting achieved with fresh mussel feed compared to formulated feeds • Inclusion of fresh mussel in formulated feeds did not provide any measurable benefit growth performance • Significant opportunities exist to improve slipper lobster growth using formulated feeds through maximising feed intake [ABSTRACT FROM AUTHOR]

The moult cycle is arguably the most critical aspect of crustacean biology and is associated with dramatic changes in behaviour, physiology and condition. Here we describe the first detailed investigation of the combined changes in morphology, physiological status and nutritional condition over the moult cycle of juvenile T. australiensis. Haemolymph refractive index (measured as Brix) was evaluated as a non-destructive method for predicting physiological status and nutritional condition. Post-moult, inter-moult and pre-moult stages were identifiable by microscopic examination of the pleopod distal tips, though differentiation of the pre-moult substages was not possible using this technique. Monitoring of ecdysial suture lines on the exoskeleton gill chambers was found to be highly useful for visually determining progression through the pre-moult stage and predicting the timing of ecdysis. A classical pattern of inter-moult growth was observed where size and wet weight remained relatively uniform over the moult cycle while highly significant changes in whole-body composition were simultaneously observed over time. Growth was most evident by changes in dry weight and dry matter content which more than doubled by the onset of pre-moult. Changes in dry matter content were generally mirrored by Brix and whole-body crude protein, total lipid and gross energy content. Brix strongly correlated with dry matter content and significant correlations were also found for all other primary measures of nutritional condition. Typical moult-related changes were also found for circulating ecdysteroids. This study clearly demonstrates pronounced cyclical changes in physiology and condition of juvenile T. australiensis over a typical moult cycle. The significant correlations between haemolymph and whole-body composition validates Brix as a practical and non-destructive method to objectively assess physiological status, nutritional condition and quality in T. australiensis and further demonstrates its potential for individual crustacean assessment in experimental research and practical commercial applications. Unlabelled Image • First detailed investigation of physiological status and nutritional condition of the slipper lobster, Thenus australiensis , over the moult • Changes in physiological and biochemical endpoints over time were highly characteristic of the crustacean moult cycle • Brix correlated strongly with moult stage and primary measures of nutritional condition • Brix provides a practical, non-destructive method for the objective assessment of physiological status and nutritional condition in captive or wild lobsters [ABSTRACT FROM AUTHOR]