Juan Carlos Azofeifa-Solano, Fresia Villalobos-Rojas, Raquel Romero-Chaves, Ingo S Wehrtmann
Abstract Biological invasions are among the main threats to the diversity of freshwater ecosystems, particularly invasions of freshwater crayfishes, which have negatively impacted native populations and ecosystem functions. Various invasions of freshwater crayfishes have been relatively well documented, allowing the use of Ecological Niche Modeling (ENM) techniques to forecast their potential invasive distribution. Modeling the most environmentally suitable areas for exotic species can provide guidelines to allocate resources, thus contributing to the control and management of invasions. We modelled the potential distribution of Cherax quadricarinatus (von Martens, 1868) and Procambarus clarkiiGirard, 1852 in Mesoamerica and the Caribbean using global occurrence data and ten environmental variables to ensemble a model using nine different algorithms. Our models showed that C. quadricarinatus has a high probability of invasion in tropical lowland areas, with the presence of exotic populations of this species already reported. Our results support that P. clarkii has a higher probability of invasion in some of the mountain ranges and plateaus of the study region, where this species has already established non-native populations. These models visualize the high-risk areas of invasion of these two non-native crayfish species in Mesoamerica and the Caribbean. A regional approach for monitoring and control of the invasive populations is encouraged as well as regulations for trade and aquaculture of freshwater crayfishes.
{"title":"Modeling the habitat suitability of two exotic freshwater crayfishes in Mesoamerica and the Caribbean: <i>Cherax quadricarinatus</i> (von Martens, 1868) and <i>Procambarus clarkii</i> Girard, 1852 (Decapoda: Astacidea: Parastacidae, Cambaridae)","authors":"Juan Carlos Azofeifa-Solano, Fresia Villalobos-Rojas, Raquel Romero-Chaves, Ingo S Wehrtmann","doi":"10.1093/jcbiol/ruad059","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad059","url":null,"abstract":"Abstract Biological invasions are among the main threats to the diversity of freshwater ecosystems, particularly invasions of freshwater crayfishes, which have negatively impacted native populations and ecosystem functions. Various invasions of freshwater crayfishes have been relatively well documented, allowing the use of Ecological Niche Modeling (ENM) techniques to forecast their potential invasive distribution. Modeling the most environmentally suitable areas for exotic species can provide guidelines to allocate resources, thus contributing to the control and management of invasions. We modelled the potential distribution of Cherax quadricarinatus (von Martens, 1868) and Procambarus clarkiiGirard, 1852 in Mesoamerica and the Caribbean using global occurrence data and ten environmental variables to ensemble a model using nine different algorithms. Our models showed that C. quadricarinatus has a high probability of invasion in tropical lowland areas, with the presence of exotic populations of this species already reported. Our results support that P. clarkii has a higher probability of invasion in some of the mountain ranges and plateaus of the study region, where this species has already established non-native populations. These models visualize the high-risk areas of invasion of these two non-native crayfish species in Mesoamerica and the Caribbean. A regional approach for monitoring and control of the invasive populations is encouraged as well as regulations for trade and aquaculture of freshwater crayfishes.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"54 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136377164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The red swamp crayfish Procambarus clarkii (Girard, 1852) is an alien invasive species as well as a commercially exploited animal. The sterile-male-release technique (SMRT) using infertile but sexually active males has been an effective candidate measure to control this invasive crayfish. Additionally, the limited supply of juveniles due to females’ spawning seasonality hinders the further development of the P. clarkii aquaculture industry. Information on its reproductive biology, such mating strategies and factors affecting offspring production, is crucial for developing an effective SMRT and aquaculture systems for P. clarkii. We review the reproductive biology of this species in terms of 1) sexual dimorphism and reproductive status, 2) sex recognition, mating, and mate preferences, and 3) egg production, embryonic development, and hatching. Intra- and intersexual dimorphisms of chelae are evident in P. clarkii, and a reproductive morphotype (form I) with larger chelae and a non-reproductive morphotype (form II) with smaller chelae are detected in both females and males, allowing us to easily determine the reproductive status of both sexes. The crayfish exhibits mutual mate choice (i.e., preference for larger mates), and small-sized males reproductive potential is low. Female fitness (i.e., number of offspring) generally depends on their body size. Female brood care appears to promote early embryo development before the egg-nauplius stage. Further study is required to identify the maternal factors affecting early embryonic development, which may improve measures for controlling invasive populations and enhancing aquaculture productivity.
{"title":"Reproductive biology of the red swamp crayfish <i>Procambarus clarkii</i> (Girard, 1852) (Decapoda: Astacidea: Cambaridae): A review","authors":"Katsuyuki Hamasaki, Shigeki Dan, Tadashi Kawai","doi":"10.1093/jcbiol/ruad057","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad057","url":null,"abstract":"Abstract The red swamp crayfish Procambarus clarkii (Girard, 1852) is an alien invasive species as well as a commercially exploited animal. The sterile-male-release technique (SMRT) using infertile but sexually active males has been an effective candidate measure to control this invasive crayfish. Additionally, the limited supply of juveniles due to females’ spawning seasonality hinders the further development of the P. clarkii aquaculture industry. Information on its reproductive biology, such mating strategies and factors affecting offspring production, is crucial for developing an effective SMRT and aquaculture systems for P. clarkii. We review the reproductive biology of this species in terms of 1) sexual dimorphism and reproductive status, 2) sex recognition, mating, and mate preferences, and 3) egg production, embryonic development, and hatching. Intra- and intersexual dimorphisms of chelae are evident in P. clarkii, and a reproductive morphotype (form I) with larger chelae and a non-reproductive morphotype (form II) with smaller chelae are detected in both females and males, allowing us to easily determine the reproductive status of both sexes. The crayfish exhibits mutual mate choice (i.e., preference for larger mates), and small-sized males reproductive potential is low. Female fitness (i.e., number of offspring) generally depends on their body size. Female brood care appears to promote early embryo development before the egg-nauplius stage. Further study is required to identify the maternal factors affecting early embryonic development, which may improve measures for controlling invasive populations and enhancing aquaculture productivity.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135567853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The alternation of the female form is examined in eleven species of Cambaridae: Cambarus angularisHobbs & Bouchard, 1994, C. bartonii (Fabricius, 1798), Faxonius virilis (Hagen, 1870), Procambarus alleni (Faxon, 1884), P. clarkii (Girard, 1852), P. fallax (Hagen, 1870), P. pallidus (Hobbs, 1940), Cambarellus leslieiFitzpatrick & Laning, 1976, C. patzcuarensisVillalobos, 1943, C. schmittiHobbs, 1942, and C. shufeldtii (Faxon, 1884). All species show form-alternation in their annulus ventralis, that of Form I showing a cornified sinus and inflated fossa, but the Form-II females show a un-cornificed sinus and deflated fossa. Morphology of the Form-II annulus ventralis is similar to that of a juvenile. A wider abdomen in Form-I females occurred in five species (C. angularis, C. virilis, C. lesliei, C. schmitti, and C. shufeldtii), and inflation of the palm of the cheliped in Form-I females was observed in four (C. angularis, C. bartonii, F. virilis, and P. clarkii). The range of morphometric female-form alternation demonstrates four patterns: 1) wider abdomen and inflated chela (C. angularis, and C. bartonii), 2) wider abdomen and no chela inflation (C. lesliei, C. schmitti, and C. shufeldtii), 3) no wide abdomen and inflated chela (F. virilis and P. clarkii), 4) no wider abdomen and no chela inflation (P. alleni, P. pallidus, and P. fallax,). A neotype of P. clarkii is also designated and described.
Abstract The alternation of the female form is examined in eleven species of Cambaridae: Cambarus angularisHobbs & Bouchard, 1994, C. bartonii (Fabricius, 1798), Faxonius virilis (Hagen, 1870), Procambarus alleni (Faxon, 1884), P. clarkii (Girard, 1852), P. fallax (Hagen, 1870), P. pallidus (Hobbs, 1940), Cambarellus leslieiFitzpatrick & Bouchard, 1994.pallidus (Hobbs, 1940), Cambarellus leslieiFitzpatrick & Laning, 1976, C. patzcuarensisVillalobos, 1943, C. schmittiHobbs, 1942, and C. shufeldtii (Faxon, 1884)。所有物种的环腹部都有形态变化，形态 I 的环腹部有粟粒状的窦和膨大的窝，而形态 II 的雌性环腹部则没有粟粒状的窦和膨大的窝。Form-II 环腹的形态与幼鱼相似。有 5 个物种（C. angularis、C. virilis、C. lesliei、C. schmitti 和 C. shufeldtii）的 Form-I 雌体腹部较宽，有 4 个物种（C. angularis、C. bartonii、F. virilis 和 P. clarkii）的 Form-I 雌体螯掌膨胀。雌-雌形态交替的形态测量范围显示了四种模式：1）腹部较宽，螯膨大（C. angularis 和 C. bartonii）；2）腹部较宽，螯不膨大（C. lesliei、C. schmitti 和 C. shufeldtii）；3）腹部不宽，螯膨大（F. virilis 和 P. clarkii）；4）腹部不宽，螯不膨大（P. alleni、P. pallidus 和 P. fallax）。还指定并描述了 P. clarkii 的新模式。
{"title":"Alternation of the female form in Cambaridae (Decapoda: Astacidea) and the designation of a neotype for <i>Procambarus clarkii</i> (Girard, 1852) (Cambaridae: Decapoda)","authors":"Tadashi Kawai, Colin L McLay","doi":"10.1093/jcbiol/ruad026","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad026","url":null,"abstract":"Abstract The alternation of the female form is examined in eleven species of Cambaridae: Cambarus angularisHobbs & Bouchard, 1994, C. bartonii (Fabricius, 1798), Faxonius virilis (Hagen, 1870), Procambarus alleni (Faxon, 1884), P. clarkii (Girard, 1852), P. fallax (Hagen, 1870), P. pallidus (Hobbs, 1940), Cambarellus leslieiFitzpatrick & Laning, 1976, C. patzcuarensisVillalobos, 1943, C. schmittiHobbs, 1942, and C. shufeldtii (Faxon, 1884). All species show form-alternation in their annulus ventralis, that of Form I showing a cornified sinus and inflated fossa, but the Form-II females show a un-cornificed sinus and deflated fossa. Morphology of the Form-II annulus ventralis is similar to that of a juvenile. A wider abdomen in Form-I females occurred in five species (C. angularis, C. virilis, C. lesliei, C. schmitti, and C. shufeldtii), and inflation of the palm of the cheliped in Form-I females was observed in four (C. angularis, C. bartonii, F. virilis, and P. clarkii). The range of morphometric female-form alternation demonstrates four patterns: 1) wider abdomen and inflated chela (C. angularis, and C. bartonii), 2) wider abdomen and no chela inflation (C. lesliei, C. schmitti, and C. shufeldtii), 3) no wide abdomen and inflated chela (F. virilis and P. clarkii), 4) no wider abdomen and no chela inflation (P. alleni, P. pallidus, and P. fallax,). A neotype of P. clarkii is also designated and described.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135994765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Victor M Laguna-Nataren, Arkady Uscanga-Martínez, Natalia Perales-García, Carlos A Álvarez-González, Francisco J López-Rasgado, José R Díaz-Gallegos, Alexis F Velazco-Ortiz
Abstract We characterized the digestive enzymes in adults of Macrobrachium americanum (Spence Bate, 1868) in southeastern Mexico. The digestive enzyme extracts were made from the specimens’ hepatopancreas. Alkaline proteases, trypsin, chymotrypsin, carboxypeptidase A, leucine aminopeptidase, lipases, α-amylase and alkaline phosphatase activities were determined, as well as the percentage of inhibition, pH, and temperature stabilities through biochemical and electrophoretic techniques. The maximum digestive activity of proteases was at 35 °C and pH 11. Alkaline digestive proteases were highly stable at pHs 4, 9 and 11 at 55 °C after 30 min pre-incubation. PMSF inhibited two bands with proteolytic activity (35.1 and 23.2 kDa), and SBT1 inhibited all bands, including the one with the highest molecular weight (64.2 kDa). We concluded that enzymes in M. americanum coincide with those of omnivorous decapods with a tendency to carnivory.
{"title":"Partial characterization of digestive proteases in the river prawn <i>Macrobrachium americanum</i> () (Decapoda: Caridea: Palaemonidae) in Mexico","authors":"Victor M Laguna-Nataren, Arkady Uscanga-Martínez, Natalia Perales-García, Carlos A Álvarez-González, Francisco J López-Rasgado, José R Díaz-Gallegos, Alexis F Velazco-Ortiz","doi":"10.1093/jcbiol/ruad053","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad053","url":null,"abstract":"Abstract We characterized the digestive enzymes in adults of Macrobrachium americanum (Spence Bate, 1868) in southeastern Mexico. The digestive enzyme extracts were made from the specimens’ hepatopancreas. Alkaline proteases, trypsin, chymotrypsin, carboxypeptidase A, leucine aminopeptidase, lipases, α-amylase and alkaline phosphatase activities were determined, as well as the percentage of inhibition, pH, and temperature stabilities through biochemical and electrophoretic techniques. The maximum digestive activity of proteases was at 35 °C and pH 11. Alkaline digestive proteases were highly stable at pHs 4, 9 and 11 at 55 °C after 30 min pre-incubation. PMSF inhibited two bands with proteolytic activity (35.1 and 23.2 kDa), and SBT1 inhibited all bands, including the one with the highest molecular weight (64.2 kDa). We concluded that enzymes in M. americanum coincide with those of omnivorous decapods with a tendency to carnivory.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134915245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jennifer E Smith, Christian Dietz, John Keane, Craig Mundy, Michael Oellermann, Caleb Gardner
Abstract Trophic discrimination or fractionation factors (TDFs), such as ∆15N and ∆13C, are used in stable isotope mixing models to account for differences between source tissues (diet/prey) and consumer tissues (predator). We aimed firstly to obtain TDF values for a spiny lobster, the southern rock lobster Jasus edwardsii (Hutton, 1875), to better understand lobster diet in the wild and secondly to investigate variability in isotope signature within tissues of individuals and across a temporal scale to test if non-lethal sampling can be used in an ecological context. We conducted an 18-mo captive feeding trial with juvenile lobsters using three diet treatments and analysed dorsal and leg muscle, along with dorsal and leg exoskeleton for δ13C and δ15N values. Average TDFs for the three diet treatments were 3.86 ± 0.98‰ (∆13C) and 5.06 ± 0.65‰ (∆15N) for leg muscle, and 4.45 ± 1.04‰ (∆13C) and 4.36 ± 0.6‰ (∆15N) for dorsal muscle. When tested against wild lobsters and prey, these TDFs outperformed multi-taxa TDFs found in the literature. Isotope values from lobster leg muscle were not identical to associated dorsal muscle but the two were highly correlated, indicating that non-lethal sampling is acceptable. Values for exoskeleton isotope were significantly different from muscle, likely due to the exoskeleton not being in a constant state of growth and replacement, unlike the muscle tissue, which constantly incorporates new material. We conclude that our experimentally derived TDFs are suitable for mixing model analysis for J. edwardsii and when tested on a wild sample of lobsters they outperformed other TDFs reported in the literature. We show that non-lethal sampling using leg muscle is an appropriate sampling method, since this tissue is highly correlated to the commonly used dorsal muscle. This option for non-lethal sampling enhances the potential to widely sample wild populations or sample during industrial processing without the need to sacrifice whole animals.
{"title":"Trophic discrimination factors and stable isotope variability in a captive feeding trial of the southern rock lobster <i>Jasus edwardsii</i> () (Decapoda: Palinuridae) in Tasmania, Australia","authors":"Jennifer E Smith, Christian Dietz, John Keane, Craig Mundy, Michael Oellermann, Caleb Gardner","doi":"10.1093/jcbiol/ruad055","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad055","url":null,"abstract":"Abstract Trophic discrimination or fractionation factors (TDFs), such as ∆15N and ∆13C, are used in stable isotope mixing models to account for differences between source tissues (diet/prey) and consumer tissues (predator). We aimed firstly to obtain TDF values for a spiny lobster, the southern rock lobster Jasus edwardsii (Hutton, 1875), to better understand lobster diet in the wild and secondly to investigate variability in isotope signature within tissues of individuals and across a temporal scale to test if non-lethal sampling can be used in an ecological context. We conducted an 18-mo captive feeding trial with juvenile lobsters using three diet treatments and analysed dorsal and leg muscle, along with dorsal and leg exoskeleton for δ13C and δ15N values. Average TDFs for the three diet treatments were 3.86 ± 0.98‰ (∆13C) and 5.06 ± 0.65‰ (∆15N) for leg muscle, and 4.45 ± 1.04‰ (∆13C) and 4.36 ± 0.6‰ (∆15N) for dorsal muscle. When tested against wild lobsters and prey, these TDFs outperformed multi-taxa TDFs found in the literature. Isotope values from lobster leg muscle were not identical to associated dorsal muscle but the two were highly correlated, indicating that non-lethal sampling is acceptable. Values for exoskeleton isotope were significantly different from muscle, likely due to the exoskeleton not being in a constant state of growth and replacement, unlike the muscle tissue, which constantly incorporates new material. We conclude that our experimentally derived TDFs are suitable for mixing model analysis for J. edwardsii and when tested on a wild sample of lobsters they outperformed other TDFs reported in the literature. We show that non-lethal sampling using leg muscle is an appropriate sampling method, since this tissue is highly correlated to the commonly used dorsal muscle. This option for non-lethal sampling enhances the potential to widely sample wild populations or sample during industrial processing without the need to sacrifice whole animals.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135588292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sergio A Ulaje, M Teresa Sicard, Ilie S Racotta, Liliana Rojo-Arreola, Salvador E Lluch-Cota
Abstract The thermal responses and tolerance of organisms can be influenced by synergistic interactions with other environmental stresses. Although the heat sensitivity of the whiteleg shrimp (Penaeus vannamei Boone, 1931 = Litopenaeus vannamei) has been extensively researched, little is known about how hypoxia impacts the thermal tolerance of the species. We assessed the thermotolerance of P. vannamei postlarvae under combined hyperthermia and hypoxia conditions. Simultaneous hypoxia significantly decreased the thermotolerance (LT50) of the postlarvae at temperatures close to the upper thermal limit of the species.
{"title":"Hypoxia reduces thermotolerance in the postlarvae of the whiteleg shrimp <i>Penaeus vannamei</i> Boone, 1931 (Decapoda: Dendrobranchiata: Penaeidae)","authors":"Sergio A Ulaje, M Teresa Sicard, Ilie S Racotta, Liliana Rojo-Arreola, Salvador E Lluch-Cota","doi":"10.1093/jcbiol/ruad052","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad052","url":null,"abstract":"Abstract The thermal responses and tolerance of organisms can be influenced by synergistic interactions with other environmental stresses. Although the heat sensitivity of the whiteleg shrimp (Penaeus vannamei Boone, 1931 = Litopenaeus vannamei) has been extensively researched, little is known about how hypoxia impacts the thermal tolerance of the species. We assessed the thermotolerance of P. vannamei postlarvae under combined hyperthermia and hypoxia conditions. Simultaneous hypoxia significantly decreased the thermotolerance (LT50) of the postlarvae at temperatures close to the upper thermal limit of the species.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"News from The Crustacean Society for September 2023","authors":"","doi":"10.1093/jcbiol/ruad050","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad050","url":null,"abstract":"","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41655407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Evelyn Beristain-Castillo, José L Salazar-Bautista, Alejandro Moyaho
Abstract Traditional methods to study precopulatory mate guarding in Hyalella azteca (Saussure, 1858) have some limitations because precopulatory pairs are usually observed in isolation. This condition precludes researchers from testing the role of the social environment in the duration of precopulatory mate guarding. We present the use of a sampling method to investigate the influence of sex ratios on guarding success (the proportion of precopulatory pairs per trial) in mixed-sex groups of H. azteca. The presence/absence of precopulatory pairs over eight consecutive days, morning and afternoon samplings, was analysed as a series of successes (runs) to estimate the mean precopula duration. The non-random nature of the observed duration of the precopula was tested against a probabilistic distribution based on the set of all ways every possible duration may occur. While skewed sex ratios increased guarding success of the rarest sex, even sex ratios decreased it. The mean duration of observed precopulas (2.32 and 2.08 d for the morning and afternoon periods, respectively) is consistent with theoretical and empirical results, which confirms the accuracy and usefulness of the sampling method we used. The use of this method and the associated probabilistic analysis of the relevant data can enhance the study of the effect of biotic and abiotic factors on precopulatory mate guarding. It can also be used to test predictions derived from hypothesis concerned with mate guarding among crustaceans.
{"title":"Guarding success of the rarest sex in the amphipod <i>Hyalella azteca</i> Saussure, 1858 (Amphipoda: Hyalellidae)","authors":"Evelyn Beristain-Castillo, José L Salazar-Bautista, Alejandro Moyaho","doi":"10.1093/jcbiol/ruad051","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad051","url":null,"abstract":"Abstract Traditional methods to study precopulatory mate guarding in Hyalella azteca (Saussure, 1858) have some limitations because precopulatory pairs are usually observed in isolation. This condition precludes researchers from testing the role of the social environment in the duration of precopulatory mate guarding. We present the use of a sampling method to investigate the influence of sex ratios on guarding success (the proportion of precopulatory pairs per trial) in mixed-sex groups of H. azteca. The presence/absence of precopulatory pairs over eight consecutive days, morning and afternoon samplings, was analysed as a series of successes (runs) to estimate the mean precopula duration. The non-random nature of the observed duration of the precopula was tested against a probabilistic distribution based on the set of all ways every possible duration may occur. While skewed sex ratios increased guarding success of the rarest sex, even sex ratios decreased it. The mean duration of observed precopulas (2.32 and 2.08 d for the morning and afternoon periods, respectively) is consistent with theoretical and empirical results, which confirms the accuracy and usefulness of the sampling method we used. The use of this method and the associated probabilistic analysis of the relevant data can enhance the study of the effect of biotic and abiotic factors on precopulatory mate guarding. It can also be used to test predictions derived from hypothesis concerned with mate guarding among crustaceans.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135098407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Mutations may lead to the evolution and diversification of color phenotypes in animals. Much of the research on this topic, however, has been conducted on vertebrates. I compile here records of color variants in freshwater crayfishes (Decapoda: Astacidea). I found color variants to be surprisingly common, with 115 documented occurrences. The overwhelming majority of these variants were blue-colored (71.3%), although there are records of document red and orange variants, among others. Whether these variants are all due to mutations or can lead to adaptive evolution in crayfishes is unknown. Some crayfish species exhibit conspicuous colors like blue, orange, and red in nature. Many of these conspicuously colored species are also semi-terrestrial burrowers, which have limited migration potential, smaller population sizes, and thus reduced gene flow compared to aquatic burrowing crayfishes. I speculate that in at least some species, conspicuous colors may be a neutral color trait that faces little to no selective pressure. This is one potential explanation as to why semi-terrestrial burrowing species are more likely to be conspicuously colored. Genetic studies and behavioral experiments are required to test this hypothesis.
{"title":"Prevalence and potential evolutionary significance of color variants in freshwater crayfishes (Decapoda: Astacidea)","authors":"Zackary A Graham","doi":"10.1093/jcbiol/ruad054","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad054","url":null,"abstract":"Abstract Mutations may lead to the evolution and diversification of color phenotypes in animals. Much of the research on this topic, however, has been conducted on vertebrates. I compile here records of color variants in freshwater crayfishes (Decapoda: Astacidea). I found color variants to be surprisingly common, with 115 documented occurrences. The overwhelming majority of these variants were blue-colored (71.3%), although there are records of document red and orange variants, among others. Whether these variants are all due to mutations or can lead to adaptive evolution in crayfishes is unknown. Some crayfish species exhibit conspicuous colors like blue, orange, and red in nature. Many of these conspicuously colored species are also semi-terrestrial burrowers, which have limited migration potential, smaller population sizes, and thus reduced gene flow compared to aquatic burrowing crayfishes. I speculate that in at least some species, conspicuous colors may be a neutral color trait that faces little to no selective pressure. This is one potential explanation as to why semi-terrestrial burrowing species are more likely to be conspicuously colored. Genetic studies and behavioral experiments are required to test this hypothesis.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Isopods of the genus Janiralata Menzies, 1951 (Asellota: Janiridae) are known from shallow and deep waters of the Northern Hemisphere. Most species are free-living, but some are symbiotic on the surface of other benthic invertebrates. We obtained from three beam- and four otter-trawl hauls 18 Janiralata asellote specimens from the bathyal zone off the Pacific coasts of Tohoku, northeastern Japan. Partial nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene (505 bp) were determined for 16 of the 18 collected specimens. Non-significant genetic differences (< 0.8%) indicated that the individuals were conspecifics. Morphological analysis indicated that all the specimens belonged to a single species, Janiralata planasp. nov. based on the unique morphology of the anterolateral and distolateral projections on the head and pleotelson, surface and lateral margins of the body, antennula article 1, and of the male pleopod 1. Six of the 18 collected specimens were found attached to the surface of an unidentified sea anemone (Hormathiidae), ten to the solasterid starfish Crossaster borealis Fisher, 1906 and two were obtained from the bottom sediment. Three COI haplotypes of the new species were shared by individuals from two neighboring sites, which suggests that genetic isolation occurs on a relatively narrow horizontal scale, although the bathymetric distribution range was rather wide. We describe a case study of the geographic and bathymetric distributions of an asellote species with low dispersal ability and its genetically differentiated populations. Such approach could help elucidate the diversity and distribution of deep-sea organisms and their diversification processes.
{"title":"A new species of <i>Janiralata</i> Menzies, 1951 (Isopoda: Janiridae) from Japanese bathyal waters, with a review of the associations with invertebrates among the species of <i>Janiralata</i>","authors":"Mizuki Ohta, Tsuyoshi Takano, Shigeaki Kojima, Yoji Narimatsu","doi":"10.1093/jcbiol/ruad049","DOIUrl":"https://doi.org/10.1093/jcbiol/ruad049","url":null,"abstract":"Abstract Isopods of the genus Janiralata Menzies, 1951 (Asellota: Janiridae) are known from shallow and deep waters of the Northern Hemisphere. Most species are free-living, but some are symbiotic on the surface of other benthic invertebrates. We obtained from three beam- and four otter-trawl hauls 18 Janiralata asellote specimens from the bathyal zone off the Pacific coasts of Tohoku, northeastern Japan. Partial nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene (505 bp) were determined for 16 of the 18 collected specimens. Non-significant genetic differences (&lt; 0.8%) indicated that the individuals were conspecifics. Morphological analysis indicated that all the specimens belonged to a single species, Janiralata planasp. nov. based on the unique morphology of the anterolateral and distolateral projections on the head and pleotelson, surface and lateral margins of the body, antennula article 1, and of the male pleopod 1. Six of the 18 collected specimens were found attached to the surface of an unidentified sea anemone (Hormathiidae), ten to the solasterid starfish Crossaster borealis Fisher, 1906 and two were obtained from the bottom sediment. Three COI haplotypes of the new species were shared by individuals from two neighboring sites, which suggests that genetic isolation occurs on a relatively narrow horizontal scale, although the bathymetric distribution range was rather wide. We describe a case study of the geographic and bathymetric distributions of an asellote species with low dispersal ability and its genetically differentiated populations. Such approach could help elucidate the diversity and distribution of deep-sea organisms and their diversification processes.","PeriodicalId":54850,"journal":{"name":"Journal of Crustacean Biology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135830659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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