Cervimunida Johni Research Articles

Using a time-dynamic food web model to compare predation and fishing mortality in Pleuroncodes monodon (Galatheidae: Crustaceae) and other benthic and demersal resource species off central Chile

The stock biomass of the carrot prawn (Pleuroncodes monodon) in the south-central area of Chile (33º–39°S) has decreased progressively in the last 12 years. The depletion and lack of recovery of carrot prawn and other fish and crustacean stocks has been attributed mostly to fishing mortality (F). Predation can be also an important factor for the dynamics of marine species, especially those that are important prey in the ecosystem, like the carrot prawn and other demersal crustaceans. However, predation mortality (M2) has been less studied and quantified in Chile and elsewhere. Therefore, it is important to estimate and compare predation (M2) and fishing (F) mortality to understand their individual and combined effects on the dynamics of fishing stocks. In this study, we analyzed the biomass changes of carrot prawn and other components of the marine food web in south-central Chile from 1992 to 2018. For this, we built a food web model that was later fit to time series of observed biomass and catch data, using observed fishing mortality as forcing factor. We used the Ecopath with Ecosim software as modeling platform. This model provided M2 and F series for carrot prawn and other demersal crustaceans, which were compared to evaluate their relative contribution to total mortality (Z) from 1992 to 2018. The quantitative model considered 29 functional groups, from primary producers to top predators, and the following fishing fleets operating in the study area: artisanal and industrial purse seine fleets, artisanal and industrial hake trawling fleet and demersal prawn trawling fleet. The results indicated that M2 was the main component of Z in adults and juveniles carrot prawns, with Chilean hake as the main predator in both cases. M2 was responsible for 84 % and 86 % of Z of adults and juveniles of carrot prawns, respectively. M2 was also greater than F in yellow prawns (Cervimunida johni), whose main predator was big eye flounder (Hippoglossina macrops). In contrast, F was greater than M2 for the nylon shrimp (Heterocarpus reedi). We conclude that the stock dynamics of the carrot and yellow prawns has been strongly influenced in recent decades by the predation by Chilean hake on pre-recruits of carrot prawn as prey and bigeye flounder on yellow prawn as prey. We recommend that M2 should be considered both in evaluating the past dynamics of these stocks used to establish their status and in future projections used to establish biologically acceptable catch.

Spatio-temporal patterns of the crustacean demersal fishery discard from the south Humboldt Current System, based on scientific observer program (2014-2019).

This study summarises six years of spatio-temporal patterns of the discarded demersal community fauna recorded by onboard scientific observer program for both artisanal and industrial crustacean fisheries between 2014 and 2019, from mesophotic to aphotic depths (96 to 650 m) along the southern Humboldt Current System (28-38°S). In this period, one cold and two warm climatic events were observed during the austral summer 2014, 2015-2016 (ENSO Godzilla), and 2016-2017 (coastal ENSO), respectively. Satellite information showed that Chlorophyll-a concentration varied seasonally and latitudinally, associated with upwelling centres, while equatorial wind stress decreased southward of 36°S. Discards were composed of 108 species, dominated by finfish and molluscs. The Chilean hake Merluccius gayi was dominant and ubiquitous (occurrence, 95% of 9104 hauls), being the most vulnerable species of the bycatch. Three assemblages were identified: assemblage 1 (~200 m deep), dominated by flounders Hippoglossina macrops and lemon crabs Platymera gaudichaudii, assemblage 2 (~260 m deep), dominated by squat lobsters Pleuroncodes monodon and Cervimunida johni and assemblage 3 (~320 m depth), dominated by grenadiers Coelorinchus aconcagua and cardinalfish Epigonus crassicaudus. These assemblages were segregated by depth, and varied by year, and geographic zone. The latter represented changes in the width of the continental shelf, increasing southward of 36°S. Alpha-diversity indexes (richness, Shannon, Simpson, and Pielou) also varied with depth and latitude, with higher diversity in deeper continental waters (>300 m), between 2018-2019. Finally, at a spatial scale of tens of kilometres, and a monthly basis, interannual variations of biodiversity occurred in the demersal community. Surface sea temperature, chlorophyll-a, or wind stress did not correlate with discarded demersal fauna diversity of the crustacean fishery operating along central Chile.

Diet of the Dusky finless skate Gurgesiella furvescens (Chondrichthyes: Rajidae) from the continental shelf and slope of the north-central area of Chile

The dusky finless skate Gurgesiella furvescens appears sporadically as part of the bycatch in the trawl fishery targeting demersal crustaceans on the continental shelf and upper slope of the north-central area of Chile (26ºS-33ºS). Demersal crustaceans could be forage for deep-water predators such as G. furvescens, and sizes and shapes of prey eaten could be restricted by mouth size. The diet composition of G. furvescens was determined based on specimens collected from the bycatch of trawls targeting demersal crustaceans in 2013. Stomach contents revealed nylon shrimp Heterocarpus reedi (32.8% by weight), deep-water shrimp Haliporoides diomedeae (7.2% by weight), and indeterminate crustaceans (9.0% by weight). The diet composition was similar between sexes, body length, or depth strata. Prey size was a linear function of Gurgesiella furvescens mouth width, and prey mass positively related with G. furvescens individual mass. Although squat-lobsters Pleuroncodes monodon and Cervimunida johni were abundant in the study area, the nylon shrimp and deep-water shrimp in the diet of G. furvescens may be due to the preference or selection of this kind of prey in deep waters.

Reproductive strategy of yellow squat lobster (Cervimunida johni Porter, 1903): re-evaluating the maturity criteria

ABSTRACT Studying the basic biology of heavily fished marine species is essential to achieving conservation and sustainable exploitation. Yellow squat lobster (Cervimunida johni) is a demersal crustacean with a long fishing history in the Southeast Pacific. However, knowledge of its reproductive biology is still fragmented, and these traits have never been validated at the gonad level. In this context, we assessed the reproductive traits of this species for the first time based on gonadal development using data from a research survey conducted during 2018 off the Chilean coast. A total of 117 and 376 gonads were assessed based on histological and macroscopic analyses, respectively. The functional and effective criteria (a combination of functional and physiological maturity) were used to estimate the maturity ogives. Using a total of 113 females, fecundity (F) and relative fecundity (RF) at length were estimated using the autodiametric method. We determined that females of yellow squat lobster possess group-synchronous ovary development with indeterminate fecundity. Histological analysis revealed that 59% of non-ovigerous females had mature ovaries and were therefore misclassified as immature based on the functional criterion. Similarly, maturity ogives derived from the effective criterion were displaced to smaller sizes and varied significantly from those estimated using the functional criterion (P < 0.05). In addition, the effects of female size on F and RF were significant (P < 0.05). A warning on the use of functional criteria for assessing maturity status is issued, and the importance of adult females on the per capita contribution to population renewal in this crustacean species is discussed .

Catch efficiency of trawl nets used in surveys of the yellow squat lobster (Cervimunida johni) estimated by underwater filming records

Catch efficiency is an important index to relate observed density to the size of a population in the context of bottom trawl surveys. The estimation of catch efficiency is challenging because it involves independent measures of animals in the path of the bottom trawl. We estimated catch efficiency using an underwater camera system on three trawl fishing vessels used for estimating the density of the yellow squat lobster (Cervimunida johni) off central Chile. During 2015 and 2018, 54 hauls were analyzed, and a total of 20 h of filming were recorded. A total of 4,155 yellow squat lobster individuals were analyzed approaching the net in the path of the trawl, of which 2,330 (56%) were captured and 1,825 escaped underneath the groundrope. The median estimated ranges of catch efficiency varied between 0.81–0.90 for vessel 1, 0.15–0.72 for vessel 2 and 0–0.58 for vessel 3. According to a hierarchical generalized linear model (HGML), fishing vessels and mean depth of hauls showed significant differences in catch efficiency (p<0.05). The results were comparable with estimates available for other crustacean species, and differences among vessels can be associated with differences in rigging configurations. Discussion was focused on the processes affecting catch efficiency and how differential catchability among sampling vessels may bias the construction of spatially explicit density maps and further abundance estimates of yellow squat lobsters in Chile.

Influence of Growth and Recruitment Parameters in the Assessment and Management Variables of the Yellow Squat Lobster (Cervimunida johni)

Fitting length data in age-structured stock assessment is a common method for evaluating hard-to-age animals, such as crustaceans. Growth specification and the uncertainty in the stock recruitment relationship are key issues in length-based assessment models. We conducted sensitivity analyses to evaluate the impact of growth and recruitment parameters on the stock assessment and management variables of the yellow squat lobster (Cervimunida johni) caught off the Chilean coast. Nine different scenarios of the length at first capture ( L a = 1 ) and the coefficient of variation at age ( c v a ) were tested for six combinations of values for the steepness parameter (h) and the recruitment variance ( σ R 2 ). We also investigated the reliability of these estimates using an operating model. Our findings indicate that the parameter related to growth, L a = 1 , has the greatest impact on the assessment and management variables of this fishery resource, with c v a having a lesser effect. Recruitment and fishing mortality estimates were the main variables affected. Parameters h and σ R 2 did not profoundly impact the variables assessed. In addition, L a = 1 was the most biased estimated parameter. We discuss that the high influence of growth parameters is related to model structure, and thus implications for determination of the status of yellow squat lobster should be addressed in the future. We recommended developing simulation protocols for the selection of growth parameters when using an age-structured model with length observations, and we believe that our findings are relevant for all Chilean fisheries with a similar stock assessment framework.

Biodiversity and biomass of bentho-demersal megafaunal assemblages of the yellow and red squat lobster fishing grounds in Central Chile (Eastern Pacific Ocean)

Biodiversity and biomass patterns of megafaunal assemblages were assessed from the yellow (Cervimunida johni) and red (Pleuroncodes monodon) squat lobster fishing grounds in the Southeastern Pacific Ocean during four years. Bottom trawls were conducted applying the swept-area method in a stratified sampling design, obtaining global and specific catch per unit area (CPUA). We recorded two target and 47 by-catch species, with a total CPUA of 80.000 t/km2 (cumulative from 2005 to 2008) Fishes and crustaceans dominated over other taxonomic groups. Classes Actinopterygii and Malacostraca attained the highest specific richness; the presence of a few dominant and many rare species in terms of CPUA and frequency, was characteristic of the studied assemblages, hence, the general CPUA pattern parallels that of the most abundant species in the bathymetric and latitudinal gradients. The three most conspicuous non-target species, Heterocarpus reedi, Merluccius gayi gayi and Hippoglossina macrops accounted for 91% of the by-catch CPUA, whereas Class Malacostraca also represented 91% of the total CPUA. The highest average specific richness occurred at intermediate depths (300–400 m) and the lowest in shallow waters (50–100m); the highest overall CPUA occurred at 100–200m and the lowest at both 400–600m and 50–100m. Depth was the most significant factor in the variability of our assemblages. However, particular features of the Humboldt Current System might act as drivers of important effects across the latitudinal gradient on the high productivity and dynamism of the squat lobster fishery, despite the homogeneous composition of the community. This study shows the importance of considering the whole biodiversity within appropriate management actions, in order to achieve ecological benefits (e.g. resilience, functional diversity, water quality, primary productivity) in communities subjected to fishing pressure.

Estimation of natural mortality in two demersal squat lobster species off Chile

AbstractNatural mortality (M) is a key parameter for understanding population dynamics, especially in relation to harvested populations. Direct observations ofMin crustaceans are scarce, due to the moulting process. Indirect methods to estimateMwith easier-to-obtain life history attributes are therefore used routinely. Given their theoretical background, we reviewed the applicability of these methods for crustaceans. We applied the selected methods to two crustacean species harvested in Chilean waters: the yellow squat lobster (Cervimunida johni) and red squat lobster (Pleuroncodes monodon). Uncertainty of eachMestimate was incorporated in the life history parameters that input into the indirect method (trait-error) and parameters defining the indirect method (coefficient-trait-error). Methods based on the relationship between total mortality and maximum age, or with different ages and based on life history theory were the most appropriate for crustaceans since they apply across taxa.Mestimates showed high variability between species, sexes and areas. Estimations ofMforC. johnivaried from 0.13 to 0.28 (year−1) for males and 0.17 to 0.51 (year−1) for females. ForP. monodonvalues for the north varied from 0.26 to 0.37 (year−1) for males and 0.24 to 0.45 (year−1) for females. In the south, values ofMwere higher for both males (0.43–0.68 year−1) and females (0.41–1.06 year−1). High variability in theMestimates was associated with the method and number of parameters, their uncertainty, theoretical background and probability distribution.Mestimates are not comparable, raising the need to propagate the uncertainty ofMinto the stock assessment of Chilean squat lobsters.

Physicochemical and in vitro cytotoxic properties of chitosan from mushroom species (Boletus bovinus and Laccaria laccata)

Chitosan samples from two mushroom species (Boletus bovinus, Laccaria laccata) were obtained and characterized by viscosimetry, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), elemental analyses (EA), nuclear magnetic resonance spectroscopy (13C NMR), X-ray diffraction (XRD) and thermogravimetric (TGA) analyses. Properties of the fungal chitosan samples were compared to commercial low-molecular weight chitosan, crustacean chitosan (Cervimunida johni) and chitosan obtained from an insect (Hilobius abietis). Additionally, the cytotoxic properties of chitosan in vitro on cancerous hepatoma and non-cancerous ovary cells cultivated on films with different chitosan concentrations was evaluated. As a conclusion, this study clearly revealed that low-molecular weight chitosan films and solutions with high degree of deacetylation can act cytotoxically on both tumor MH-22A and normal CHO cells in vitro. Consequently, this work may be useful for further investigations of natural anticancer products in medical areas.

Using a spatio-temporal Bayesian approach to estimate the relative abundance index of yellow squat lobster (Cervimunida johni) off Chile

Estimating relative abundance indexes based on spatio-temporal variations in fishing effort has been one of the greatest challenges in fisheries sciences. Obtained from the catch per unit of effort (CPUE), such indexes are generally used within evaluation models as "relative" to the stock abundance. Herein, a Bayesian spatio-temporal model was used to obtain an index for yellow squat lobster (Cervimunida johni) between the III and IV regions of Chile based on CPUE data (Kg/h.a) from fishing logs. The spatial field was approximated by a GMRF using the SPDE method and posterior distributions of interest were approximated using the Integrated Nested Laplace Approximation (INLA). By taking into account the distributional assumption of the CPUE the proposed model showed a good fit to the observed data. The proposed method allowed obtaining a relative index of abundance which could be included within the classic stock assessment models.

Variation in cheliped form in two species of squat lobsters (Decapoda: Anomura) from Chile

AbstractThe current study describes the variation in cheliped form of two species of squat lobsters that inhabit the continental margin off Chile: Cervimunida johni and Pleuroncodes monodon. We compared their cheliped form in the context of the reproductive strategy. The general tendency of form variation of both species is similar: chelipeds change, on average, from longer and narrower pollex with short manus to a relatively shorter and wider pollex with longer manus from small to large individuals, respectively. The degree of cheliped arching was greater in males than in females of similar carapace length, and only C. johni males showed fully arched morphology. The allometric trajectories (cheliped shape vs. carapace length) were largely aligned with vectors of mean shape difference in both species. Cheliped form variation of C. johni (extended mate-guarding) resembles the cheliped morphology reported for the related species Munida rugosa more than P. monodon (short mate-guarding). Our results are consistent with previous finding and suggest that the cheliped form variation (from straight and slender to a fully arched morphology) is, or has been, subject to sexual selection through male-male competition for mates.

Preparing valuable renewable nanocomposite films based exclusively on oceanic biomass – Chitin nanofillers and chitosan

Added-value bionanocomposite films were obtained using exclusively oceanic biomass, i.e. chitin nanofillers (nanocrystals- CHNC and nanofibers- CHNF) and chitosan (CS) isolated from Cervimunida johni (yellow lobster) wastes. From these raw materials two sets of bionanocomposite films (CS/CHNC and CS/CHNF) using CS as matrix and CHNC or CHNF as functional agents were prepared by solvent evaporation-casting approach. The bionanocomposite films’ chemistry, structure, mechanical and thermal properties and fungal growth inhibition toward A. niger were analyzed, and the effect of the CHNC and CHNF on the final properties of CS-based bionanocomposite films was evaluated and compared. The data demonstrated that the final properties were dependent of the content and nano nature (size and shape) of chitin nanofillers incorporated in the CS matrix. The CS-based bionanocomposite films reinforced with CHNF showed superior mechanical properties than those prepared with CHNC. Moreover, antifungal assessment demonstrated that CS/CHNF bionanocomposite films presented an inhibitory effect (FGI >80%) against A. Niger. Unquestionably, these bionanocomposite films show a great potential to be used in packaging applications and medical devices.

Caracterizacion de agregaciones de langostino colorado (Pleuroncodes monodon) y langostino amarillo (Cervimunida johni) mediante un sistema de filmacion remolcado

To characterize red squat lobster ( Pleuroncodes monodon ) and yellow squat lobster ( Cervimunida johni ) aggregations a towed video system was used to cover a seabed area in the Coquimbo region, Chile. The films were made in 2009 and 2010, at depths between 102 and 215 m. Estimated average densities of P. monodon and C. johni varied between 3 and 63 ind m -2 and between 0.2 and 2.8 ind m -2 , respectively. Mating couples of C. johni were observed on July 2009 (∼200 m depth). The results show that the towed video system is an effective means of recording specimens of both species, allowing both the quantitative characterization of the stock and the observation of the species behavior and habitat. The system has the potential for use in direct assessment of abundance and habitat characterization both biotic and abiotic.

Estimacion de la biomasa de langostino amarillo (Cervimunida johni), aplicando Modelo Lineal Generalizado a registros de captura por area barrida en la zona central de Chile

Changes in the annual density of the yellow squat lobster (Cervimunida johni) were modeled using a generalized linear model (GLM), using information obtained during direct stock assessment cruises carried out in central Chile (32°-38°S) between 1997 and 2009. The purpose of this approach was to minimize the effect of different sampling criteria and designs that have been used over time and to determine the factors explain in variations in the density of this resource. The above approach allowed estimating the expected value of the annual density for the biomass calculation through the method. By using the haul-to-haul records of catch per unit of the swept area (CPUA), it was possible to identify and measure the points of abundance and characterize the distribution and area occupied by the resource over time. The significant effects identified by the GLM were the year, zone, depth, and first-order annual interactions; which explained 43% of the residual deviance in the model. The main effects that explain the CPUA variations are the year and the year-zone interaction. The zone with the greatest average abundance was located between 32° and 34°S; the same was for the depth range <250 m. Within the period analyzed, the biomass of the population of this resource increased steadily until 2006, mainly in the northern zone of the study area, followed by a sharp reduction 2009, that is 75% compared to the maximum and results in a biomass of 11,000 ton.

Annual brood number and breeding periodicity of squat lobsters (Decapoda: Anomura: Galatheidae) from the continental shelf of the SE Pacific—Implications for fisheries management

The reproductive potential of a population depends on the number of broods that individuals produce during the annual reproductive season. Determining the annual brood number is especially relevant for species that are actively fished. Herein we combined different approaches to estimate the annual brood number of two commercially exploited species of squat lobsters from the Chilean continental shelf and upper slope, Cervimunida johni and Pleuroncodes monodon. Long-term maintenance in the laboratory revealed that most females (>70%) produced 3 or more broods during the annual reproductive season. Incubation of individual broods required about 40 days, which would allow for 3 subsequent broods during the main reproductive period (June–September). The dynamics of brood release of ovigerous females that were collected from the field at approximately monthly intervals supported the estimate of 3–4 annual broods for adult females. Furthermore, these latter data also indicated a high degree of breeding synchrony among reproductive females. It is suggested that the production of successive broods might be an adaption to the variable oceanographic conditions during the reproductive period, ensuring that at least one larval cohort finds favorable conditions for development and settlement. Based on these results it is recommended that fishing effort is reduced during the main reproductive period of the two squat lobsters.

Estimating yellow squat lobster (Cervimunida johni) biomass by applying a generalized linear model to catch records per swept area in central Chile

Changes in the annual density of the yellow squat lobster (Cervimunida johni) were modeled using a generalized linear model (GLM), using information obtained during direct stock assessment cruises carried out in central Chile (32°-38°S) between 1997 and 2009. The purpose of this approach was to minimize the effect of different sampling criteria and designs that have been used over time and to determine the factors explain in variations in the density of this resource. The above approach allowed estimating the expected value of the annual density for the biomass calculation through the “swept area” method. By using the haul-to-haul records of catch per unit of the swept area (CPUA), it was possible to identify and measure the points of abundance and characterize the distribution and area occupied by the resource over time. The significant effects identified by the GLM were the year, zone, depth, and first-order annual interactions; which explained 43% of the residual deviance in the model. The main effects that explain the CPUA variations are the year and the year-zone interaction. The zone with the greatest average abundance was located between 32° and 34°S; the same was for the depth range

Alternative codends to improve the size selectivity for nylon shrimp (Heterocarpus reedi) and yellow squat lobster (Cervimunida johni) off the Chilean coast

The size selectivity of alternative codends for nylon shrimp and yellow squat lobster was studied off the Chilean coast using the covered codend technique. Various mesh sizes (47 and 63 mm mesh opening) and shapes (diamond and square) in the codends were used. For both species, substituting the DM47 codend with the DM63 codend significantly increased 50% retention length (l50). The change of diamond (DM47) to square mesh (SM47) had a positive effect in size selectivity for nylon shrimp. For yellow squat lobster, no significant effect was observed when changing the diamond (DM63) to square mesh (SM63). Selectivity data were modeled by considering explanatory variables such as ‘codend catch weight’ and ‘vessel’. Increases in the catch significantly reduced the l50 for both species whereas the vessel factor was not significant. Finally, using the length at first maturity as a reference value, the authors concluded that the DM47 codend failed to protect the immature portion of either stock, thus the DM63 codend is recommended.

Caracterizacion de las tacticas de pesca en la pesqueria multiespecifica de crustaceos demersales en Chile

In multispecies fisheries, each fishing operation can be described by analyzing the catch composition, fishing location, and fishing gear used. Sets of fishing operations with similar characteristics have been usually defined as fishing tactics. The present work defines fishing tactics for the crustacean multispecies fishery (CMF) developed between 26o03’S and 38o28’S off Chile. The catch composition per fishing haul, as recorded by scientific observers in fishing a logbooks from 2007 to 2009, was used. During this period, 1599 fishing hauls containing 57 species were registered in total. After employing a principal component analysis to reduce the species composition dimension, an agglomerative hierarchical analysis was carried out over the retained components. Four fishing tactics were identified and analyzed: 1) effort directed to Heterocarpus reedi (red shrimp) over a wide latitudinal range, 2) effort focused on Cervimunida johni (yellow squat lobster) in a narrow latitude range and at shallower depths, 3) effort directed to Haliporoides diomedeae (red royal shrimp), with the deepest hauls, and 4) effort focused on Pleuroncodes monodon (red squat lobster) in shallower waters close to the coast. In the case of the CMF, the identification of fishing tactics is important for indicating catch intention and for constructing abundance indices using data derived from fishing a logbooks. The results are discussed in terms of characterizing the fishing tactics and how their designation allows obtaining less biased abundance indices.

Reproductive biology of two species of squat lobsters – female receptivity and interbrood intervals

The reproductive biology of many species of anomuran crabs is only poorly known. Herein we studied the reproductive biology of two species of squat lobsters, Cervimunida johni Porter, 1903 and Pleuroncodes monodon (H. Milne Edwards, 1837), which are target of a trawl fishery operating on the continental margin along the Chilean coast. During the reproductive period (May-November) we maintained squat lobsters in the laboratory to examine whether mating is related to the reproductive molt of the female and to determine the interbrood interval between successive broods. In both species females mated during the intermolt period. Females became receptive shortly after having released larvae from a previous brood, when they formed pairs with males. The interbrood interval (from larval release until having a subsequent brood) lasted <72 hour in the majority of female C. johni, but was longer in P. monodon, where most females took 72-144 hours before producing a new brood. Despite longer interbrood intervals, copulatory mate-guarding was substantially shorter in P. monodon than in C. johni. These differences in reproductive behavior might be due to differences in the general biology of the two species, including mobility and intraspecific aggression. Mating during the intermolt period may have several advantages, namely reducing the risk of cannibalism and energy costs of molting during the reproductive season.

Distribution and abundance of Heterocarpus reedi Bahamonde, 1955, Cervimunida johni Porter, 1903, and Pleuroncodes monodon (H. Milne Edwards, 1837), larvae off Coquimbo and Caldera, Chile

To better understand the population dynamics of fishery resource species, 160 zooplankton samples were obtained with a Bongo net at 40 oceanographic stations around Caldera and Coquimbo in October and December, 2005, and analyzed. All crustacean decapod larvae were sorted, and Heterocarpus reedi, Cervimunida johni, and Pleuroncodes monodon larvae were identified. For all three species, the highest abundances of early zoea were found in October in Coquimbo, whereas advanced larval stages were predominant in December. In Caldera, advanced larval stages of H. reedi and P. monodon, and early zoeas of C. johni were dominant during both sampling months. The frequency of occurrence of H. reedi larvae was similar during both sampling months in Coquimbo and greater in October in Caldera. The frequency of occurrence of the larvae of P. monodon and C. johni was greater in both areas in October. All the megalops captured in both zones and sampling months corresponded to a single morphotype, with morphological characteristics similar to the smallest P. monodon juvenile specimens. Based on the larval distribution and abundance of these three species, it is postulated that spawning occurs earlier in the Caldera area than around Coquimbo, mainly in areas near the coast, given the differences in abundance of the developmental stages.