To facilitate submissions to the Journal of Crustacean Biology, we offer guidelines to provide some structure and advice to potential authors. Science is intrinsically fascinating, but scientists need to present their results in a way that conveys that fascination. Above all, JCB seeks submissions of interesting and readable papers with a strong evolutionary slant or other added value that maximizes their likely audience. The submission, review, and editorial process should facilitate this goal.

The paired fronto-lateral gland pores and lattice organs (LO1, 2, 3, 4, and 5) of seven species of pedunculate barnacles belonging to two thoracican suborders, Heteralepadomorpha (family Heteralepadidae: Heteralepas sp. 1 and 2) and Lepadomorpha (families Poecilasmatidae: Poecilasma inaequilaterale and Octolasmis aymonini geryonophila; and Lepadidae: Lepas pacifica, Dosima fascicularis, and Conchoderma virgatum), were investigated by scanning electron microscopy (SEM). While the fronto-lateral gland pores exhibit slight variation among species, with only L. pacifica showing a different morphology, the variations in the arrangement of LOs are phylogenetically instructive. The lattice organs in the foregoing species correspond in general to the inferred advanced type (Type C), but the distinct keel in the pore field in P. inaequilaterale and L. pacifica is reminiscent of, but not necessarily identical with the less advanced Type B. The arrangement of the anterior LOs (1-2) is rhomboidal in the two heteralepadomorph species, the two poecilasmatid species, and two of the three lepadid species, as it is in all previously and presently known lepadomorph cyprids except D. fascicularis. In this last species, they are deployed linearly along the hinge line. A linear arrangement of all the lattice organs is presumably the plesiomorphic condition for the Thoracica; an obvious exception being the pattern seen in Ibla cumingi. The arrangement of the first two pairs of posterior LOs (3-4) in O. a. geryonophila and C. virgatum differs from that of all previously described Lepadomorpha in being rhomboidal rather than aligned linearly along the hinge line. This same arrangement of LOs 3 and 4 in the two heteralepadomorph species is notable since it is not known in other thoracicans. Our results concerning variation in lattice organs of the lower Pedunculata are more or less consistent with current phylogenetic speculations and genetic information that ally Heteralepadomorpha with Lepadomorpha. Significance of this variation at lower taxonomic levels is also evident in the two similar forms of Heteralepas.

The dotillid crab Ilyoplax pusilla performs waving displays during the reproductive season. When a female approaches a male, he often directs his waving at her. More often, however, males do not direct their waves at any particular individual. We conducted a field experiment that manipulated neighbors' sex to clarify whether either of the sexes was more often the target of waving displays. Waving frequency by males with male neighbors was significantly higher than that of males with female neighbors. Waving frequency was correlated with the number of active male neighbors but not with the number of active female neighbors. These findings suggest that waving display of I. pusilla is performed through male to male competition.

We describe techniques that enable the preservation of tissues from the rhizocephalan barnacle, Loxothylacus texanus, inside the body cavities of blue crab hosts, Callinectes sapidus, in a manner that minimizes the degradative activities of hepatopancreatic enzymes. These procedures allow the extraction and amplification of both parasite and host 18S rDNA within the same sample and enable one to distinguish between parasitized and unparasitized crab tissue in as little as two weeks after infection, well before any external manifestations of the parasites. Two PCR-based approaches were taken to identify the presence of L. texanus. In the first approach, a set of primers specific for L. texanus was used to specifically amplify 18S sequence in a background of C. sapidus DNA or the DNA of other barnacle species. In the second approach, a set of general primers was used to amplify 18S sequence from C. sapidus and a variety of barnacle species. The products of this PCR were then digested with an enzyme that recognizes a restriction site present only in the L. texanus PCR product to yield a unique pattern of fragments. With these techniques, we could detect as few as five parasitic cypris larvae in water samples, as well as L. texanus in the tissue of a small crab collected from the field and in the four anterior periopods of a crab bearing the external stage of the parasite. In experiments with potential hosts of varying sizes and molt stages, we confirmed that the parasite was significantly more effective in infecting crabs less than 30 mm carapace width than larger individuals. These techniques will facilitate future investigations of ecological and physiological interactions between these important crustacean parasites and their hosts and will help to determine the economic impact of this parasite on blue crab fisheries.

The population structure and energetic burden of bopyrid isopod parasite Orthione griffenis on the eastern Pacific mud shrimp Upogebia pugettensis are estimated from size and weight relationships between parasite and host. U. pugettensis weight loss increases with O. griffenis weight but the high variance in the relation indicates that direct weight comparisons are insufficient to reveal most of the host-parasite energetic interactions. Environment, reproductive development, age, molt stage and the feeding histories of the hosts and parasites, not apparent from weight ratio comparisons, are likely to be important factors in their interaction. The high prevalence of O. griffenis among U. pugettensis and positive correlation between host weight loss and parasite weight nevertheless, indicate large impacts of these parasites on mud shrimp populations are occurring with corresponding effects on estuarine dynamics in Pacific Northwest estuaries.

Sequence analyses on the intron from the elongation factor-1α gene were conducted to examine the population structure of sword prawn (Parapenaeopsis hardwickii) in the East China Sea and Taiwan Strait. Five samples including 207 individuals were separately collected from the north of East China Sea (NECS) and waters off Tamsui, Taichung, Putai, and Cheding, and 102 alleles were identified. Despite no phylogeographic structure in alleles, pairwise F_ST values and analysis of molecular variance (AMOVA) showed significant genetic difference between the NECS and the other four samples. The UPGMA tree of five samples showed two distinct clusters; one included the NECS sample; the other included the rest of samples. The results suggest that two populations exist in the East China Sea and Taiwan Strait. To ensure resource sustainability and maintenance, the sword prawn in the Taiwan Strait and the north of the East China Sea should be treated as two separate populations and then be separately managed in future. Both Tajima's D and Fu and Li's D statistics and analysis of mismatch distribution for overall alleles suggested that sword prawn in studied area had experienced population expansion.

Multivariate statistical methods were employed to study the morphological variation of the freshwater shrimp (Atyaephyra desmarestii), sampled from four distinct freshwater habitats of northwestern Greece. Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA) were used in order to determine morphometrical differences among the biological categories (males, females and ovigerous females) and sampling sites. Statistical analysis of A. desmarestii morphometrical and population data showed that body heights and growth of appendages are correlated to biological category. Females found to have higher values for the measured body heights than males. On the other hand, morphometrical variables related mainly to body lengths such as rostral, telson and pleon lengths, were observed to be correlated to the study sites. Characters related to the swimming capacity, such as telson length, telson width, and pleon lengths, were generally found to have higher values in ovigerous females. Furthermore, among the four ecosystems, certain variables demonstrated higher values in the fluvial ecosystems and lower values in the lacustrine.

We evaluate whether the abundance of the freshwater crabs Aegla itacolomiensis and A. platensis is related to any or all of 11 environmental variables. We sampled 205 Surber samples (33 × 33 cm) in a stream five meters wide in southern Brazil. For each Surber sample we obtained measures of flow velocity, depth, type of substrate, and availability of coarse particulate organic matter. The relationships between abundances of the two species and the environmental variables were assessed by regression trees. Only 2 of the 11 environmental variables were important in describing the abundances of the two species, both of them related to availability of coarse particulate organic matter. The abundance of Aegla itacolomiensis was related positively to quantity of fragmented leaves and, to a lesser degree, to quantity of twigs. For the abundance of A. platensis, quantity of twigs, followed by fragmented leaves, were the most important environmental factors. The quantity of recently fallen, unfragmented leaves was unimportant. We conclude that the two species of Aegla select locations with abundant old plant fragments that are usually colonized by fungi and bacteria. This conclusion is corroborated by previous studies indicating that Aegla spp. feed mostly on plant fragments.

Knowing important aspects of life history, such as size at sexual maturity, growth rate, and size at age, is critical for understanding species' population dynamics. For harvested organisms, these life-history characteristics are important in assessing the efficacy of fishery regulations. We used a 15-year database on stone crabs (genus Menippe) inhabiting west-central Florida waters to estimate these life-history aspects. Transition points in crusher-claw propodus length (PL):CW allometry and discriminant function analysis indicated that 50% morphological maturity (CW₅₀) occurred at approximately 70 mm CW for males and 60 mm CW for females. Patterns in the proportions of physiologically mature (gravid) and functionally mature (ovigerous) females in 10-mm-CW size-classes followed the female morphological maturity pattern. The CW₅₀ was significantly smaller than the mean size at behavioral maturity (participation in mating) in males (86 mm CW), but was not in females (62 mm CW). In both sexes, PL:CW allometry also shifted at 30-35 mm CW, allowing us to define three life stages: small juvenile, large juvenile, and adult. Male PL:CW allometry increased dramatically in adulthood, whereas adult-female PL:CW allometry remained the same as that of large juvenile females. Molt frequency decreased with increasing size in both sexes; molt increment increased with increasing size in males but increased only up to CW₅₀ in females. Adult males and females molt annually in cycles dictated by female reproduction. Males enter the commercial fishery during age three and females during age four. Females have contributed to the reproductive population prior to entering the fishery, but most males probably have not.

The most significant events of the reproductive cycle of the Patagonian stone crab, Platyxanthus patagonicus, were studied in specimens sampled in northern Patagonian gulfs from August 2004 to May 2006. Male and female crabs were assigned to stages of a scale of gonad maturity. Females were also classified according to the presence/absence of embryos on the pleopods and of spermatic content in the spermathecae. Ogives were fitted to maturity at size data. The highest frequency of pre-ovigerous females and spermathecae with hardened seminal contents occurred during the fall and winter. Fifty percent of the females reached ovarian maturity at 66.4 mm CW. Ovigerous females were frequent from mid-fall to mid-spring, peaking during early winter and mid-spring, and were unusual or absent during the summer months. Post-ovigerous females were present in samples in all months but May and June 2005, being frequent from late-spring to early-fall. Specimens with spent ovaries were common in all seasons but summer, while those with mature or recovering ovaries were present in samples taken in all months but August 2004 and May-June 2005. Fifty percent of the males reached testes maturity at 54.7 mm CW. Males larger than this size showed mature gonads year round, but a pulse of individuals with recovering testes was observed during the winter of 2005 and early-fall of 2006. Our results show that mating occurs during the fall months, spawning and embryonic incubation extends from fall to early spring, and hatching takes place during late-spring and early-summer.

There are six stages in the naupliar phase of development of Tegastes falcatus (Norman, 1869). The labrum is expressed as a simple fold which does not cover the mouth. A poorly-sclerotized mouth tube was observed on some specimens of all stages except NI (= naupliar stage 1); NI and NII are the only stages without an anus and presumably do not feed. The antennal endopod is a subchela against itself at NII; its distal endopodal segment becomes bifurcate at NIII. A chela on the naupliar mandible consists of the endopod opposite a distoventral attenuation of the basis on NII-NVI. The segmental elements of a chela are present at NI, although the endopod does not oppose the basis at this stage. The maxillule is a unilobe bud with one seta at NIII that gains a second seta at NV and is transformed into a simple bilobe bud with three setae at NVI. The maxilla and maxilliped are each an asetose, ventral attenuation at NVI. Naupliar stages, found in large numbers along with all six copepodid stages of T. falcatus, apparently feed on suctorian ciliates growing on colonies of the bryozoan Flustra foliacea (Linnaeus, 1758). This is the first description of six naupliar stages for a species of Tegastidae Sars, 1904.

Although most parasitic copepods produce free-living larvae, Caribeopsyllus amphiodiae and other thaumatopsyllid copepods have a parasitic larval stage (metanauplius) that inhabits an ophiuroid stomach. Metanauplii of C. amphiodiae collected from its burrowing host, Amphiodia urtica, and reared in the laboratory gave rise to ovigerous females that released free-swimming first nauplii (NI). We provide the first full descriptions for a thaumatopsyllid of the NI, parasitic metanauplii, and free-living copepodid I to copepodid VI of the female and male based on developmental stages obtained. Extraordinary features of C. amphiodiae NI are the presence of one pair of setae on the labrum, a character unique among Copepoda, and the presence of a maxillule represented by one seta, making the larva a metanauplius by definition. In most other copepods, the one-seta or one-spine maxillule appears no earlier than NII. The mandible of the metanauplius becomes massive, and a spiniform process from the first endopodal segment forms a chelate complex with the distinctly curved, clawlike second endopodal segment. Transient vestiges of the antenna and mandible remain in the CI, but maxillule, maxilla, and maxilliped are absent during the copepodid phase. Other body structures appear earlier than reported for other copepods: pediger 5 and the bud of swimming leg 4 are present at CI, and pediger 6 and the buds of legs 5 and 6 are present at CII. During leg development setal development is accelerated, but ramal segmentation is delayed. In addition, the major body articulation of the copepodid and adult stages occurs between the third and fourth pedigers, unlike the tagmosis of most gymnoplean and podoplean copepods. Such shifts in the timing of ontogenesis, atypical naupliar morphology, and unique adult body set apart the thaumatopsyllids from other copepods.

The Caribbean spiny lobster (Panulirus argus) is the most widespread, commercially important, and extensively studied spiny lobster in the western hemisphere, yet until now it has never been successfully reared through all its planktonic (phyllosomal) stages from egg to early benthic juvenile. Here we describe the development of phyllosomal P. argus in culture including the growth, duration, and morphology for 10 distinct stages. Phyllosomata were cultured from egg to juvenile in two ways: 1) in individual cultures using small glass bowls (120 and 400 mL) to determine individual growth, and 2) in group culture using a 40 L elliptical tank to obtain samples for morphological descriptions. Six of the 20 phyllosomata cultured individually (at 25-27°C ) metamorphosed after 18-21 molts (mean = 20) to the puerulus stage at 140-198 days (mean = 174 days). Body lengths of the final stage phyllosomata and pueruli ranged from 25.6 to 28.2 mm (mean = 27.0 mm) and 16.4 to 17.5 mm (mean = 17.0 mm), respectively. Of the 550 mass cultured (at 25°C) phyllosomata, 146 were sampled for morphological examination and subsequently divided into 10 stages, each described and illustrated herein. This is the first of the five Panulirus species known from the Atlantic Ocean to be cultured completely from hatch to settlement. This success is crucial for future research on larval behavior and dispersal and may renew interest in aquaculture of this economically consequential species.

Larval release by adult fiddler crabs occurs during the ebbing tides, but its timing relative to the day-night and tidal amplitude cycles depends upon tidal form, e.g., shows phenotypical plasticity. Crabs (Uca thayeri) from Florida's East Coast are exposed to semidiurnal tides and release their larvae at night, whereas crabs from Florida's West Coast are exposed to mixed tides and release their larvae during the afternoon. The purpose of this study was to determine whether the larvae would hatch at other times, specifically those dictated by females from a different coast. To find out, clusters of eggs at similar stages of development, 24-72 h in advance of release, were reciprocally transferred between females from each location. Release of both the transferred and maternal larvae occurred synchronously, at the time dictated by the female's tidal regime. These results indicate that fiddler crab embryos can either advance or delay their hatching clock to match the temporal regime dictated by a brooding female.

This study compares timing of egg extrusion, embryo development, timing and duration of eclosion, and incubation periods of Kodiak, Alaska, primiparous and multiparous Tanner crabs (Chionoecetes bairdi) reared in identical conditions to determine if and how these variables differ between reproductive states. Female reproductive state (primiparous or multiparous) and dates of egg extrusion were recorded, eggs were sampled monthly to determine egg stage and area, and larvae were collected daily during eclosion to determine timing and duration of eclosion. Primiparous Tanner crabs extruded eggs on average 103 days earlier than multiparous females and embryos developed similarly between groups. Both groups exhibited an embryonic developmental diapause at the gastrula stage, but the length of diapause was approximately 6 months for the primiparous group and 3 months for the multiparous group. This diapause appears to synchronize eclosion. The eggs of primiparous Tanner crabs were significantly smaller than the eggs of multiparous females for a few months after extrusion, but the differences may not be biologically significant. Eclosion was relatively synchronous between the two groups, however the mean eclosion date was 10 days earlier for primiparous females and on average, eclosion took 7 days for primiparous females and 12 days for multiparous females. Primiparous Tanner crabs have an average incubation period of 489 days which is 92 days longer than the average multiparous female incubation period of 397 days. Results of this study clearly illustrate that reproductive cycles differ between primiparous and multiparous Tanner crabs which may result in different reproductive potentials. Differences between primiparous and multiparous Tanner crabs must be understood and included in models for effective stock assessment, fishery management plans, and rebuilding plans.

The morphological characteristics of the zoeas and crabs of the false spider crab Elamenopsis ariakensis are described and their habitats are documented, with an emphasis on their symbiosis with the burrowing sea cucumber Protankyra bidentata. The 16 zoeas and 91 crabs were collected from the Ariake Sea and adjacent Yatsushiro Sea, Japan. Zoeas have no lateral spine, whereas the rostral and dorsal spines are extremely long. In all zoeal stages, the pleon consists of six segments, including the telson. Adult crabs have fused pleons, with five segments in males and three segments in females, including the telson, but six segments are found in young male crabs. All crabs were collected from P. bidentata burrows. In addition to E. ariakensis, seven commensal species were collected from P. bidentata burrows: two crabs, four bivalves, and one scale worm. The microhabitats in the burrow of P. bidentata were divided somewhat among species.

In examining the surface sculpture of the eggs of extant clam shrimps, chiefly from China, at least four types can be recognized. 1) Ridge-type eggshells have a variety of features, but all eggshell surfaces are ornamented with stout protruding ridges separated by deeply wide valleys. The surface can be textured with numerous minute pores. This pattern is unique to Limnadidae. 2) Reticular-type eggshells are spherical in aspect with large polygonal reticulations, which is seen in the taxa of Leptestheriidae (diameter 85-110 μm). 3) Hairy-type eggshells are covered by numerous hairy ornaments. Occasionally, crowded minute dots fill in among hairy structures (diameter 115-160 μm), and these types may belong to Cyzicus and Caenestheriella. 4) Ripple-type eggshells are spherical with a densely ripple sculpture (diameter 90-150 μm). This type is commonly seen in species of Eocyzicus (Cyzicidae) or Lynceus (Lynceidae). Therefore, the eggshell morphology is a useful character for identification at either the high taxonomic or the species level. In terms of egg diameter, the extant eggs are quite similar to those of fossil eggs from the Lower Permian (100-110 μm) of Germany and the Middle Jurassic (c.130 μm) of China. Likewise, the shape and size of the eggs of kazacharthrans from the Upper Triassic of China are somewhat similar to those of cyzicids. They are much smaller (150-160 μm) than that of extant notostracans (> 400 μm). In general, the anostracan eggs are larger than those of clam shrimps in size and less than in number, such as seen in a new taxon from the Middle Jurassic being 220-240 μm. However, Chirocephalus rasnitsyni from the Lower Cretaceous of Russia (c.200 μm) is similar to those of clam shrimps. Fossil cladoceran ephippia found from Early Permian to Quaternary ranges from 300 μm to 500 μm. They are easily distinguished from both extant and fossil clam shrimp egg forms.

Three new species of Lophomastix Benedict, 1904, L. boykoi, L. kellyi, and L, altoonaensis are described from the upper Eocene-upper Oligocene Lincoln Creek Formation and the lower to middle Miocene Astoria Formation of Washington State, USA. Previously only one other fossil Lophomastix, L. antiqua Schweitzer and Boyko 2000, had been described from the upper Eocene Quimper Formation of Washington. The two extant species of Lophomastix have a limited geographic distribution in the northwestern Pacific Ocean from Russia to Korea and in the northeastern Pacific from southern California to Baja California (Boyko, 2002). The description of two new Eocene and one new Miocene species suggests Lophomastix originated and was well established in the northeastern Pacific from the late Eocene through at least the early to middle Miocene.

We investigated four morphologically affiliated species of Macrobrachium in northeastern Asia (M. nipponense and M. formosense, which spawn many small eggs, and M. shokitai and M. asperulum, which spawn a few large eggs). Multi-locus allozyme analysis supported the hypothesis that M. shokitai, endemic to the southernmost island (Iriomote Island) of the Ryukyus, Japan, differentiated recently (approximately 1.0 Myr ago) from nearby M. asperulum populations in Taiwan. M. nipponense and M. formosense are inferred to have differentiated later (0.48 Myr ago). The group of M. shokitai and M. asperulum was presumed to have separated from the group of M. nipponense and M. formosense in several million years, evolving their characteristic reproductive traits. Some populations of M. shokitai and M. asperulum in upland streams show extremely low genetic variability.

A new genus and species of bopyrid isopod infests the deep-water galatheid crab Munidopsis beringana collected at a depth of 4100 m off the central coast of California. The head of the female Goleathopseudione bilobatus n. gen., n. sp. is separated from the first pereiomere as in Pleurocryptella, but differs from this and Bathione in having three pairs of lamellae in the barbula and well-developed coxal plates, in the shape of the biramous sub-cylindrical pleopods, and in the absence of uropods. Goleathopseudione is morphologically similar to Pleurocryptella with respect to the absence of lateral plates, and to Bathione with respect to the unsegmented maxillipedal palp. The male of the new genus is close to Pleurocryptella as they both have a well-developed bi-articulated maxillipedal palp, and it is different from it and Bathione in having a sub-ovoid flap covering the sixth segment dorsally. Goleathopseudione is the third genus of bopyrid isopod that infests the host genus Munidopsis in the eastern Pacific, and the second described for a depth greater than 4000 m.

Ten species belonging to three genera of the subfamily Pontoniinae were colleted by the deep-sea expedition “PANGLAO 2005” in the Philippines, including four new species of the genus Periclimenes, i.e., P. boucheti n. sp., P. leptunguis n. sp., P. ngi n. sp., and P. panglaonis sp. nov., and one newly recorded species from the Philippines, Periclimenes laccadivensis. They are reported with color photographs except one species, Plesiopontonia monodi. The possible synonymy of Periclimenes foresti and P. granuloides is discussed.

Somatic tissues in mature copepods are determinate in growth, not undergoing mitosis; cell number remains constant throughout adult life. Here we report evidence of polyploidization for eight species of cyclopoid copepods. Using static Feulgen-DNA cytophotometry, we measured individual somatic nuclei in populations of Eucyclops ensifer from Brazil and of Eucyclops agilis from Ohio, U.S.A. Small but potentiality significant percentages of the adult somatic cells in these species, as well as in Bryocyclops caroli, Halicyclops tagea, Macrocyclops albidus, Mesocyclops edax, Mesocyclops thermocyclopoides, and Thermocyclops decipiens, contained at least twice (4C) the amount of DNA found in their diploid (2C) cells. These species have 2C DNA values that are representative of the range of genome sizes in cyclopoid copepods which, as a group, have much smaller genomes than calanoid copepods. Polyploidy may be a previously unrecognized mechanism whereby copepods alter the DNA content or nucleotype during specific stages in development. DNA reduplication preceding a cycle of endomitosis may result in a doubling of the functional genome, thus providing additional template for mRNA transcription related to specific functions.