Female Carapace Research Articles

The genera Chrysillaand Phintelloidesrevisited with the description of a new species (Araneae, Salticidae) using digital specimen DOIs and nanopublications.

Two Southeast Asian spider collections: that of Frances and John Murphy, now in the Manchester University Museum and the Deeleman collection, now at the Naturalis Biodiversity Center in Leiden constituted the basis of this analysis of Chrysilla Thorell, 1887 and related genera. The latter collection also includes many thousands of spiders obtained by canopy fogging for an ecological project in Borneo by A. Floren. Some incongruences within the genera of the tribe Chrysillini are disentangled. The transfer of C.jesudasi Caleb & Mathai, 2014 from Chrysilla as type species of Phintelloides Kanesharatnam & Benjamin, 2019, based on analysis of molecular data is validated by morphology. An interesting new species known only from the forest canopy in Borneo, Phintelloidesscandens sp. nov, is described based on both male and female specimens. Distinguishing chrysilline genera is mostly based on traditional somatic characters, e.g., habitus, carapace and abdomen patterns, mouthparts, and genital organs. The utility of two character systems for distinguishing chrysilline genera is highlighted: 1) the presence of a flexible, articulating embolic tegular branch (etb) in combination with the conformation of the characteristic construction of the epigyne in Chrysilla and Phintelloides; 2) presence of red colour on carapace and abdomen of live males and females, in combination with abundant blue/violet/white iridescent scales such as inChrysilla and Siler. The red colour usually gets lost in alcohol, hampering species identification of alcohol material. The genera Chrysilla andPhintelloidesare redefined. Specimens of the heretofore unknown female of Chrysilla deelemani Prószyński & Deeleman-Reinhold, 2010 are described. The male and female ofChrysillalauta and male of C.volupe are redescribed. The genus Chrysilla is diagnosed and discriminated from PhintellaBösenberg & Strand, 1906, SilerSimon, 1889, Phintelloides Kanesharatnam & Benjamin, 2019 andProszynskiaKanesharatnam & Benjamin, 2019. The structure of the female genital organ of Phintelloidesflavumi Kanesharatnam & Benjamin, 2019 is scrutinized and the generic placement of Phintelloides is discussed. Males and females of one of the most variable species, Phintelloidesversicolor (C. L. Koch, 1846) are redescribed.Phintelloidesmunita(Bösenberg & Strand, 1906) is removed from synonymy with P.versicolor. Phintellaleucaspis Simon 1903 (male, Sumatra) is synonymized withP.versicolor.Biodiversity data are increasingly reliant on digital infrastructure. By linking physical specimens to digital representations of their associated data, we can lower barriers to information flow. Here we demonstrate a workflow whereby persistent identifiers (PIDs) in the form of DOIs issued by DataCite are assigned to specimens. Recognized taxa are identified by their catalog of life identifier, or by registration in ZooBank where no catalog of life identifier is available. We demonstrate the use of nanopublications, creating a series of machine readable, scientifically meaningful assertions regarding the provenance and identification of cited specimens. All human agents associated with the specimen data are linked to a persistent identifier issued by either ORCiD or Wikidata.

Mysidopsis jenseni n. sp. from the Pacific coast of Washington, with first description of female M. intii Holmquist, 1957 (Crustacea: Mysida: Mysidae).

Mysidopsis jenseni n. sp. is described from the Puget Sound area, Washington, USA from sand/rocky bottoms in depths of 8 to 15 m. This new species increases the number of American Pacific species of Mysidopsis to eight. Based on a collection of M. intii Holmquist, 1957 from coastal waters of Chile, a supplementary description of the male is presented and the female is described for the first time. The presence of a mid-dorsal lappet near the posterior margin of the carapace of females only distinguishes the new species from all other Mysidopsis species except M. velifera Brattegard, 1973 from the Caribbean. M. jenseni is further separated from its American Pacific congeners by the following combination of characters: antennal scale 34 times as long as wide with a rounded apex and distal suture; uropodal endopod with 89 spiniform setae along ventromedial margin; telson with 4654 spiniform setae along all margins. The presence of lobe-like protuberances on the basis and dactylus of thoracic endopods 38 was documented for the new species, M. intii and other species of Mysidopsis as well as species belonging to the other four genera within the Tribe Mysidopsini. A key to the species of Mysidopsis of the Pacific coasts of the Americas is given.

Struktura populacije atlantskog plavog raka, Callinectes sapidus na istočnoj obali Jadrana (Hrvatska, Crna Gora)

The Atlantic blue crab, Callinectes sapidus, is a highly invasive species that poses a significant threat to Mediterranean ecosystems. In the last two decades, it has become established in several marine and estuarine areas of the eastern Adriatic Sea, resulting in a decline in commercial catches and damage to fishing gear. This article reviews the current status of blue crab invasion in Montenegro and Croatia and analyses its abundance and population structure. Overall 619 crabs were sampled (male:female ratio, 1:1.91). Both carapace width and weight differed significantly between males and females, with males having a wider carapace and more weight. There was a significant difference in carapace width and weight among sites. For the total population, the mean male and female carapace width was 130.3 ± 30.8 and 108.8 ± 41.4 mm, respectively. In addition, the mean male and female weight was 187.2 ± 85.6 and 132.5 ± 39.1 g, respectively. Coefficient b between the weight and carapace width of blue crabs was significant at all locations, although it varied between males and females. This work will also document the impacts of the blue crab invasion on local ecosystems and provide comprehensive overview of populations structures and shed light on this important aspect of blue crab ecology.

The genus Platytyphlops (Cumacea: Crustacea): A new species from Argentina, taxonomic status of Platytyphlops orbicularis (Calman, 1905), and remarks on the genus

Platytyphlops uteae n. sp. is described based on a few specimens collected off the coast of Buenos Aires Province at 1011–1712 m depth during the surveys Atlantis II 60 (1971) and Talud Continental III (2013). In addition, Platytyphlops orbicularis, a species described by W. T. Calman in 1905 based on a single fragmentary specimen from West Ireland, is briefly redescribed. Furthermore, the specimens from the east coast of USA assigned to P. orbicularis by Calman in 1912, are herein considered to be conspecific with P. uteae n. sp. These two species are closely related. P. uteae n. sp. can be easily separated from P. orbicularis by: (1) the absence of submedian carinae on the carapace (present in P. orbicularis), (2) the female carapace being as wide as long (wider than long in P. orbicularis); and (3) the fifth pereopod as long as the fifth pereonite (much shorter than the fifth pereonite in P. orbicularis). Platytyphlops is a diverse genus that currently encompasses 24 species. Based on morphological data, three species groups within this genus are herein proposed. In addition, the bathymetrical range of all the species currently in Platytyphlops are updated and compared.

Fattening in Saline and Alkaline Water Improves the Color, Nutritional and Taste Quality of Adult Chinese Mitten Crab Eriocheir sinensis.

The majority of pond-reared Chinese mitten crab (Eriocheir sinensis) grow and fatten in freshwater. Previous studies illustrated that E. sinensis cultured in saline-alkaline water in outdoor environments showed a higher quality than that cultured in freshwater. However, it is still unclear whether salinity or alkalinity has an important positive effect on the quality of E. sinensis. This study aimed to investigate the gonadal development, edible yield, coloration, and nutritional and flavor quality of E. sinensis fattening in saline and alkaline water indoors. Results showed that there were no significant changes observed in gonadosomatic index (GSI) and other edible parameters among freshwater (FW), saline water (SW), and alkaline water (AW) during the 55-day fattening period (p > 0.05). Significantly higher a* and b* values of freeze-dried female carapace were observed fattening in SW and AW compared with that of FW (p < 0.05). The crude protein in gonad and male muscle, moisture in female muscle, and crude lipid in male muscle increased significantly from FW to SW and AW (p < 0.05). Better nutritional and flavor values were also detected in male hepatopancreas and muscles. In conclusion, numerous advantages of fattening in SW and AW were observed, including the improvement of carotenoid accumulation in freeze-dried carapace, DHA, EPA, total essential free amino acids (∑EFAA), total free amino acids (∑FAA), and total umami values (∑TUV) contents in male hepatopancreas and muscle.

The distribution and population ecology of semaphore crab Ilyoplax sayajiraoi Trivedi, Soni, Trivedi and Vachhrajani 2015, on mud flat region of Gulf of Khambhat, Gujarat, India

The semaphore crab Ilyoplax sayajiraoi is a newly discovered species distributed in the Gulf of Khambhat, Gujarat, India. Consequently, almost no information is available regarding its population structure. The distribution of species is limited to upper most reaches of the gulf and thus any alteration in the habitat will eventually affect its population. Studies on the population structure of I. sayajiraoi will provide baseline data for future studies and probably, it has potential to serve as a bioindicator species. Morphometric measurements of the carapace (width and length), cheliped and body weight were measured for specimens, collected monthly. The growth was not isometric, demonstrating a significant difference in carapace of males and females, giving sexual dimorphism. Relationship established between carapace width and weight indicate that species is allometric in nature. Sex ratio was 1.3 : 1 (M : F). Ovigerous female and juvenile recruitment showed a bimodal distribution pattern for maintaining the overall size of population.

Heavy metal concentration levels and biometric analysis of Liocarcinus depurator from different locations on the western Black Sea coast of Turkey.

The aim of the current work is to examine the concentrations of nine heavy metals such as chromium, nickel, copper, cadmium, zinc, cobalt, iron, lead, and metal (aluminium) in two body parts (carapace and walking legs) of Liocarcinus depurator from different stations (İlyas bey, Cide koyu, Anadolu feneri, igneada) in the western Black Sea coast of Turkey. And this study was carried out to examine morphological properties of Liocarcinus depurator in the region. The sex ratio (female/male) of 387 samples was calculated as F/M = 1:0.945. The mean carapace length and width were measured as 20.41 ± 2.41mm and 25.10 ± 2.78mm for female and 25.49 ± 3.33mm and 32.32 ± 4.50mm for male individually. The mean weight of crabs was measured as 4.09 ± 1.37g for females and 8.33 ± 3.35g for males. The samples were investigated trace metals by inductively coupled plasma-optical emission spectrometry (ICP-OES). Ranges over trace metals in all samples of L. depurator as follows: Cr 0.6-1.5, Mn 21-130, Cu 8-37, Zn 6-40, Cd 0.2-1.5, Pb 0.1-3.6, Co 0.1-1.1, Fe 22-160, and Ni 0.6-1mg/kg wet wt. The walking legs and carapace/exoskeleton of female and male crabs were analyzed and contained various concentrations of Pb, Co, Ni, Cr, Cd, Fe, Cu, Zn, and Mn elements. The order of the heavy metal in all samples of L. depurator is shown as Fe > Cu > Mn > Zn > Cr > Cr > Ni > Cd > Pb > Co. In this research, metal levels of the crab samples compared between female and male and found highest mean metal concentrations in the station number 3 (Anadolu feneri) that the Al concentration in the carapace of female was 295.0mg/kg wet wt and in the walking legs was 306.67mg/kg wet wt, in the carapace of male was 264.4mg/kg wet wt, and in the walking legs was 162.61mg/kg wet wt in station number 3 (Anadolu feneri). The purpose of this work is to analyze the metal composition of this type of crab, which is abundant in the Black Sea region and is not planned to be attached to fisherman's nets, to evaluate whether it will be useful or not.

REPRODUCTIVE TRAITS OF NORTH AMERICAN CAJUN DWARF CRAYFISH (CAMBARELLUS SHUFELDTII) FROM THE NECHES RIVER NATIONAL WILDLIFE REFUGE

The Cajun dwarf crayfish (Cambarellus shufeldtii) is among the most broadly ranging dwarf crayfish species in North America. Little is known about the species' reproductive cycle in east Texas populations, and even less is known about the relationship between female body size and reproductive traits. This study seeks to characterize some reproductive traits of female C. shufeldtii as they correlate to body size. We recorded measurements of 23 berried specimens collected from an east Texas freshwater marsh, and established a positive correlation between female carapace length and number of eggs, as well as female total length and number of juveniles. Females were larger and had larger clutches than those reported from Louisiana. We also present some laboratory evidence for females reproducing multiple times in a single reproductive season.

Evaluation of the ontogeny and sexual dimorphism in a new species of Middle Triassic Darwinulocopina (Crustacea, Ostracoda) from Argentina

AbstractDarwinulocopina is an interesting group of ostracods that includes some of the first invaders of freshwater habitats during the late Palaeozoic. The Permian–Triassic extinction greatly reduced their diversity, culminating in a single extant family. The darwinulids are regarded as ‘ancient asexuals’ given that a parthenogenetic mode of reproduction is assumed for all post‐Triassic members of the group. However, the high diversity achieved during the late Palaeozoic is often associated with sexual reproduction. Here we studied a monospecific assemblage of ostracods from the Middle Triassic of the Cuyo Basin, Province of Mendoza, Argentina, recognizing a new species of Darwinulocopina,Prasuchonella?huarpesp. nov. We discuss the traditional length/height and length/width graphical method for identifying ontogeny/sexual dimorphism in fossil ostracod assemblages. A geometric morphometric analysis was performed on both lateral and dorsal views of almost 170 carapaces, to evaluate the ontogeny and sexual dimorphism of the species. The best results were obtained from the analysis in dorsal view, discriminating four ontogenetic stages. This revealed a main ontogenetic trend related to the development of the brooding chamber. Although subtle in difference, female carapaces are wider not only at the brooding chamber, but also along the whole length, compared with the presumptive males. We provide full systematic descriptions and discussions, attempting to unify descriptive criteria for recent and fossil darwinulocopine carapaces, and suggest closeness to species previously described from the upper Permian of Russia. As a result, we recommend a review of Mesozoic records of Darwinulocopina, particularly those from the Triassic.

Growth and longevity of the spider crab Libinia ferreirae (Majoidea, Epialtidae)

Abstract We estimated the growth parameters of the spider crab, Libinia ferreirae (age, asymptotic size and growth rate) using the von Bertalanffy growth equation model. We obtained nine cohorts for female carapace asymptotic width (CW∞) = 64.32 mm, growth coefficient (day-1) (k) = 0.0027 e t0= 0.77 days) and seven for males (CW∞ = 81.93 mm, k= 0.0021 e t0= 0.49 days). The longevity for males was higher than that for females, estimated 2,156 days (5.91 years) and 1,706 days (4.68 years), respectively. The growth curves for males and females differed (F = 34.67 e p < 0.001). Males reached gonadal maturity before morphometric maturity and occurred at 8.8 and 16.6 months of life, respectively. Females reach gonad and morphometric maturity synchronously and this was estimated to occur at about 11.42 months of life. These crabs invest a great amount of energy in growth during a brief period of their development until reaching the terminal moult. This growth strategy would bring less wear to the organism and consequently a greater longevity.

The Shape of Weaver: Investigating Shape Disparity in Orb-Weaving Spiders (Araneae, Araneidae) Using Geometric Morphometrics

Sexual size dimorphism in orb-weaving spiders is a relatively well-studied phenomenon, and numerous works have documented evolutionary variation in interspecific size and degree of dimorphism. To date, these studies have been largely limited to assessing the evolution of a single or few linear measurements correlated with body size. While the descriptive and comparative literature is rich with qualitative and linear comparisons that distinguish the sexes and characterize species, the extent to which interspecific or dimorphic variation in size correlates with morphological shape remains relatively unexplored. The carapace of spiders is generally conserved in shape, especially among members of the same family, but is neither well-characterized as a potential facet of spider sexual dimorphism nor as a variable structure overall. Here, we use geometric morphometric techniques to quantify differences in carapace shape among members of the family Araneidae and test for allometric influences on interspecific and dimorphic shape differences across orb-weavers. We show that females and males differ in shape, occupying overlapping but distinct areas of morphospace, with males having more piriform carapaces than females. Araneid spider subfamilies overlap substantially in morphospace, though interspecific differences in shape are generally greater than those distinguishing males and females of a species. Furthermore, we show that female carapace shape shows phylogenetic signal and is more conserved than is male shape. Carapace shape differences made evident from canonical variates analysis are congruent with the more mobile lifestyle adopted by males, as a broader carapace may support more robust leg musculature.

Sexual dimorphism in the claws of the European terrapin (&lt;em&gt;Emys orbicularis&lt;/em&gt;): potential implications for the reproductive fitness of the species.

There are many biometric differences between the males and females of the European pond turtle (Emys orbicularis) as regards their size, colouring, the shape of the plastron, tail, etc. The males use their claws to grasp the female during copulation and hence sexual selection should favour the males that have larger claws, which allow them to grasp the female better. Here, we address this type of sexual dimorphism in a comparative analysis of indices obtained from claw length, the length of the carapace and the locality where individuals were sampled. The results show that the curvature of the claws differs between the two sexes, being longer in males and increasing with age, size, and hence, the state of sexual maturity, than in females. Greater claw length could confer advantages for males when grasping the carapace of females, and hence, improve their reproductive fitness. Importance in the reproductive success that might have this feature in males could originate future studies that will relate the shape, thickness, length and other measures of the claws in males with their reproductive success in different populations, genetic variety, and most importantly, viability of populations.

Defatted Haematococcus pluvialis meal can enhance the coloration of adult Chinese mitten crab Eriocheir sinensis

Defatted algal meal, a by-product of carotenoid extraction from Haematococcus pluvialis, still contains a certain level of astaxanthin and other nutrients, which is considered as a potential ingredient or additive for aquafeeds. This study was conducted to investigate the effects of dietary supplementation of defatted H. pluvialis on gonadal development, coloration, and antioxidant and immune capacity of adult Chinese mitten crab, Eriocheir sinensis. Three isonitrogenous (crude protein: 42% of dry diet) and isolipidic (crude lipid: 16% of dry diet) experimental diets were formulated to contain 1% defatted H. pluvialis meal (Diet 1), 0.2% whole H. pluvialis powder (Diet 2), and without supplementation of astaxanthin (Diet 3, control diet). Therefore, there were three treatments with four replicate tanks for each treatment, and each tank had 12 crabs (6 males and 6 females). For the color parameters, no significant differences were found between Diet 1 and 2 treatments. The values of hepatopancreas lightness (L* = 62.65) and carapace redness (a* = 20.29) of male crabs from Diet 1 treatment were significantly higher compared to those (L* = 53.94, a* = 17.87) of Diet 3 treatment; while the a* values of ovaries (a* = 26.28) and carapace (a* = 19.93) of female crabs from Diet 1 treatment were significantly higher than those (ovarian a* = 18.28, carapace a* = 16.30) of Diet 3 treatment. The total carotenoids contents in the hepatopancreas (243.73 mg kg −1 dry matter) and carapace (73.44 mg kg −1 dry matter) of male crabs fed Diet 1 were higher than those (133.50, 43.14 mg kg −1 dry matter) of Diet 3 treatment. The contents of total carotenoids in the ovaries (356.50 mg kg −1 dry matter), hepatopancreas (120.88 mg kg −1 dry matter) and carapace (79.61 mg kg −1 dry matter) of females fed Diet 1 were significantly higher than those (290.92, 76.04 and 61.77 mg kg −1 dry matter, respectively) of Diet 3 treatment; while the astaxanthin contents in the ovaries (174.69 mg kg −1 dry matter) and carapace (19.97 mg kg −1 dry matter) of females from Diet 1 treatment were significantly higher than those (25.65, 13.87 mg kg −1 dry matter) in the Diet 3 treatment. For the antioxidant capacity indices, the male crabs from Diet 1 treatment had the lower levels of superoxide dismutase, peroxidase, glutathione reductase and malondialdehyde in the serum as well as the activities of glutathione peroxidase and peroxidase in the hepatopancreas than those of Diet 3 treatment (P < .05), but no significant differences were found between Diet 1 and 2 treatments. For the immune indices, dietary supplementation with defatted H. pluvialis significantly increased the activities of acid phosphatase, alkaline phosphatase in the serum of male crabs as well as the levels of serum alkaline phosphatase, hemocyanin and nitric oxide of female crabs compared to Diet 3 treatment (P < .05). In conclusion, dietary supplementation of defatted H. pluvialis meal can enhance the coloration, antioxidant and immune capacity, and reduce the cost of a fattening diet for E. sinensis.

Morphological Variability Among Broods of First-Stage Blue Crab (Callinectes sapidus) Zoeae.

External morphology has been shown to influence predation and locomotion of decapod larvae and is, therefore, directly related to their ability to survive and disperse. The first goal of this study was to characterize first-stage blue crab zoeal morphology and its variability across larval broods to test whether inter-brood differences in morphology exist. The second was to identify possible correlations between maternal characteristics and zoeal morphology. The offspring of 21 individuals were hatched in the laboratory, photographed, and measured. Zoeae exhibited substantial variability, with all metrics showing significant inter-brood differences. The greatest variability was seen in the zoeal abdomen, rostrum, and dorsal spine length. A principal component analysis showed no distinct clustering of broods, with variation generally driven by larger zoeae. Using observed morphology, models of drag induced by swimming and sinking also showed significant inter-brood differences, with a maximum twofold difference across broods. In contrast to trends in other decapod taxa, maternal characteristics (female carapace width and mass and egg sponge volume and mass) are not significant predictors of zoeal morphology. These results suggest that brood effects are present across a wide range of morphological characteristics and that future experiments involving Callinectes sapidus morphology or its functionality should explicitly account for inter-brood variation. Additionally, inter-brood morphological differences may result in differential predation mortality and locomotory abilities among broods.

Short Communication: Biological aspects of Charybdis anisodon (De Haan, 1850) in Lasongko Bay, Central Buton, Southeast Sulawesi, Indonesia

Hamid A, Wardiatno Y. 2018. Short Communication: Biological aspects of Charybdis anisodon (De Haan, 1850) in Lasongko Bay, Central Buton, Southeast Sulawesi, Indonesia. Biodiversitas 19: 1755-1762. Data on the biological aspects of Charybdis anisodon (De Haan, 1850) were still very limited. This study was aimed to determine the distribution of size, growth type, sex ratio and spawning season of C. anisodon in Lasongko Bay, Central Buton, Southeast Sulawesi. Crab collection was conducted from May 2013 to March 2014 using a crab gillnet. The carapace width of males and females C. anisodon ranged between 3.05-7.61 cm and 3.45-7.98 cm, respectively. Mann-Whitney test showed that width and length of carapace of males and females were significantly different (p&lt;0.05). Type of growth of carapace width-body weight male and female were both allometric negative. Carapace length-body weight relationships of the males was isometric, but it was allometric negative for females. Spatially and temporally, the sex ratio of C. anisodon showed a variation, and the total sex ratio was 1: 0.38. The spawning season of C. anisodon tend to occur throughout the year.

Experimental evidence for the genetic benefits of female mate choice in the monandrous wolf spider Pardosa astrigera

Material and/or genetic benefits are hypothesized to be the main drivers of female mate choice. Research on female mate choice has mainly focused on polyandrous species and has seldom considered monandrous species. Given the absence of postcopulatory mate choice in monandrous females, we predicted that precopulatory mate choice is important for monandrous species. Using the wolf spider Pardosa astrigera as a model monandrous species, we compared mating, reproductive output and offspring fitness between females with preferred mates (mates that were accepted on the first exposure) and females with nonpreferred mates (mates that were rejected on the first exposure but were induced to mate on the second exposure). Our results showed that the mating duration, latency to egg laying and to egg hatching, fecundity and egg hatching rate did not differ significantly between females with preferred versus nonpreferred mates. In contrast, female and male development time was significantly shorter and female carapace width was significantly greater for offspring of females with preferred versus nonpreferred mates. In addition, survival from egg hatching to maturity was twice as high for offspring of females with preferred mates. These results indicate that female mate choice by the monandrous P. astrigera provides genetic rather than material benefits.

The carapace matters: refinement of the instantaneous growth rate method for Antarctic krill Euphausia superba Dana, 1850 (Euphausiacea)

Growth of Antarctic krill Euphausia superba Dana, 1850 is commonly calculated using the Instantaneous Growth Rate (IGR) method based on the difference between the uropod lengths of the moulted exoskeleton and the uropod lengths after moulting. To date, this method has not accounted for sex-dependent differences in body proportion, relying only upon uropod measurements. We measured the carapace, uropod, and total body lengths of gravid females, non-gravid females, males, and juvenile krill from the Indian Sector of the Southern Ocean. Growth rates derived using a combination of the carapace and uropod measurements for gravid females were different from those derived through the traditional uropod-only based IGR, whereas non-gravid females, male, and juvenile growth rates showed no significant difference between methods. The refined method we propose successfully reflects dimorphism in growth between the sexes of krill, with gravid females having enlarged carapaces during the reproductive season. The interaction between growth and reproduction must be considered to improve the reliability of predictions from krill life history models, which is possible through the use of sex-dependent IGR measurements. We propose that, whenever possible, measurements of carapace and total length should be made along with uropod measurements. Together with assessments of maturity stages of krill that did not moult during experiments, these measurements will aid in further informing krill stock assessments.

A new pea crab species of the genus Arcotheres Manning, 1993 (Crustacea: Decapoda: Brachyura: Pinnotheridae) from India.

A new species of pinnotherid crab, Arcotheres shahi n. sp., is described on the basis of specimens collected during a crustacean survey along the coastal areas of Pamban fishing harbor in the Gulf of Mannar, Tamil Nadu state, east coast of India. The new species resembles A. pernicola (Bürger, 1895), A. winckworthi (Gordon, 1936) and A. rayi Ahyong Ng, 2007, in having the dactyli of the longer fourth pereopod longer than that of fifth pereopod. Arcotheres shahi n. sp. differs from these three known species in the shape of female carapace, frontal region and chela, setal pattern on the dactyli of the fourth and fifth pereopods and relative length of the ambulatory pereiopods.

Elemental characterization of the exoskeleton in the whipscorpions Mastigoproctus giganteus and Typopeltis dalyi (Arachnida: Thelyphonida)

AbstractThe arthropod cuticle is a structurally diverse secretion that is largely composed of lipids, proteins, and α‐chitin that function together in protection, prey capture, and as a skeletal framework for efficient and diverse means of locomotion. Aquatic, aerial, and terrestrial arthropods are well known to enrich their cuticles with trace elements that are proposed to strengthen or otherwise enhance specific regions of the exoskeleton. In this study, we provide evidence that whipscorpions (vinegaroons) enrich their exoskeleton with up to 14 trace elements. We use energy‐dispersive x‐ray spectroscopy (EDS) to provide the first comparisons of trace element composition in two species of Thelyphonida: Mastigoproctus giganteus (female) and Typopeltis dalyi (female and male). We analyzed the chemical composition of eight regions that have sensory, locomotory, taxonomic, protective, and/or predatory significance: the flagellum, prosoma, tarsal claws of the walking legs, tarsi of the antenniform legs, chelicerae, and the terminal three segments of the pedipalps. Our results reveal the presence of 14 trace elements across both species (12 elements in T. dalyi, 10 elements in M. giganteus), and only four elements are present at significant levels (≥1% weight): Si, Cl, Ca, and Zn. The flagellum, antenniform leg tarsi, and prosoma keel lack these elements in both species, while the chelicerae of all species are enriched with Ca, Zn, and Cl, and the tarsal claws are enriched with Zn. Significantly, we note the presence of Si in the prosomal carapace (but not the keel) of males and females of Typopeltis only, which appears to be the first evidence of this transition metal in the arthropod exoskeleton. We discuss the significance of these chemical enrichments in whipscorpions and provide hypotheses about their functional significance.

Notes on the reproductive ecology of the rough-footed mud turtle (Kinosternon hirtipes) in Texas, USA

Kinosternon hirtipes is among the least-studied North American turtles and little is known concerning reproduction. In the United States, K. hirtipes occurs at < 10 sites within a single creek drainage in Presidio County, Texas where it is considered a threatened species. We investigated the reproductive ecology of one of these populations at Plata Wetland Complex in 2007. We captured nine female K. hirtipes in wire mesh traps and hoop nets baited with fish. Eggs were obtained by injecting females with oxytocin. We recovered 19 eggs from six females captured in May and June. The smallest female that produced eggs was about 7.1 years old. Mean (± 1SD) clutch size, egg length, egg width, egg mass, and clutch mass were 3.1 ± 1.4 eggs, 28.7 ± 1.4 mm, 17.5 ± 0.9, 5.3 ± 0.6 g, and 17.5 ± 0.8 g, respectively. Relative egg mass and relative clutch mass were 0.035 and 0.011, respectively. There was a significant, positive linear relationship between female carapace length (CL) and egg width. The relationship between CL and relative egg mass was negative, and approached statistical significance. Relationships between CL and clutch size, egg length, and egg mass were not significant. Reproductive attributes of K. hirtipes in Texas are similar to those reported from a population in Mexico.