Scaling of the pieces of the Aristotle's lantern in five species of Strongylocentrotus (Echinodermata: Echinoidea)

The lengths of the demipyramids and rotules and the weights of the demipyramids, rotules, epiphyses, compasses, and teeth of the Aristotle's lantern from Strongylocentrotus droebachiensis, S. franciscanus, S. intermedius, S. nudus and S. purpuratus over a size range of 46–76 mm horizontal diameter were measured. The rates of increase in size of the lantern pieces of S. franciscanus when scaled with increase in body size are greater than those of the other species. The growth of S. franciscanus to a much larger body size and its continued increase in relative gonadal production at a size at which it ceases in S. intermedius and S. purpuratus may result from a greater feeding capacity related to the size of the lantern pieces.     

Morphometric structure and allometry profiles of the giant red shrimp Aristaeomorpha foliacea (Risso, 1827) in the eastern Mediterranean

The relative growth of body parts, such as abdomen, uropod, scaphocerite, telson, rostrum, and the third pereiopod of males and females of the giant red shrimp (Aristaeomorpha foliacea, Risso, 1827) was studied in samples from the Greek Ionian Sea (eastern Mediterranean) in 1999–2000. These were related to carapace length, sex and size of individuals. A length–weight relationship was also obtained. In general, a negative allometry of swimming appendages (uropod, scaphocerite), abdomen (related to metabolic processes), and length of the third pereiopod (involved in walking ability) was observed in both sexes. Growth of the telson was positively allometric in females and negatively allometric in males. Asynchronous growth of the male rostrum was also noted. Appendages were proportionally longer in juveniles than in adults of both sexes. A strong negative allometry between length–weight for both sexes was shown, and females were heavier than males in all sampled months.     

Relative growth and sexual dimorphism of the South Atlantic hermit crab Loxopagurus loxochelis (Anomura,Diogenidae) from Ubatuba,Brazil

Some morphometric relationships and biometric aspects were studied in the hermit crab Loxopagurus loxochelis (Moreira, 1901) with the purpose of describing its relative growth and finding the size where sexual maturity is reached. Specimens were collected monthly from September 1995 to August 1997 in the Ubatuba region using double-rig trawl nets. A total of 1084 specimens (625 males and 459 females) was analysed. In this species, sexual dimorphism is particularly evident in chela dimensions. Differences between males and females were found in the left propodus length versus cephalothoracic shield length (CSL) and wet weight (WW) versus CSL relationships. Males showed a high positive allometry in chela growth, while females were close to isometry/negative allometry. The size at which a clear differentiation occurred in the growth of the propodus length and in the increase in weight of males and females was between 4.5 and 6.0mm CSL, suggesting that size at which sexual maturity is reached.     

Size criteria for the distinction between Cylindroiulus londinensis (Leach) and Cylindroiulus caeruleocinctus (Wood) (Diplopoda: Julidae)

Ring number, body height and live weight are given for each stadium and sex of two Cylindroiulus species often confused in the literature. In each stadium there is no overlap between the height and weight of the two species, which makes it possible to identify specimens using size criteria alone. According to data from different places in Europe, intraspecific variation is not substantial enough to fill the size gap between the two species.     

Intertidal distribution,symbiotic association and reproduction of Pinnotheres bidentatus (Brachyura: Pinnotheridae) from Taiwan

The intertidal distribution of the free-swimming stage of the pea crab Pinnotheres bidentatus Sakai, 1939 was examined on the Kaomei coastal flat of western central Taiwan. Most pea crabs were collected from tidal waters close to the shoreline regardless of the collecting treatments utilized. Results suggest that the pea crab population remains inshore during ebb tides. Many hard and post-hard stages of P. bidentatus were discovered, including ovigerous females. The host was found to be Laternula marilina (Valenciennes, 1860) (Mollusca: Bivalvia: Laternulidae). The infestation percentage of the bivalve was high (average 74.6%). However, this may be due to collections of the bivalve population in the present study being skewed towards large sizes. This biased size structure of the host population may be also responsible for lack of positive size correlation between number and size of male and female symbiotic crabs and the host. Multiple infestations of P. bidentatus appear to be uncommon for L. marilina. Single infestations might be a model for bivalves in tropical regions where the sea is relatively oligotrophic and food competition may be enhanced with multiple infestations. In comparison to other members of the genus Pinnotheres or related species (e.g. P. pisum (Linnaeus, 1767) and Zaops ostreum (Say, 1817)), the body size of sexually mature female P. bidentatus is relatively small, even though it produces similar size eggs (approximately 300 microns). The general rule for size correlation between fecundity and female size in brachyuran crabs holds for P. bidentatus.     

Carapace epibionts of loggerhead turtles (Caretta caretta) nesting at Canaveral National Seashore,Florida

A survey of the epibionts inhabiting the carapace of loggerhead sea turtles Caretta caretta (Linnaeus) nesting on Canaveral National Seashore, Florida was conducted from 2003–2004. Epibionts were sampled and identified to the lowest taxonomic level possible. Eleven newly documented epibiont species were observed from 52 individual loggerheads. We present the first records of sea urchins as loggerhead epibionts. Data are presented on the behavioural, physical, and ecological characteristics of some of these newly documented species to understand better the relationship between loggerhead turtles and their epibiota.     

The size variable and allometric analysis in the barnacle genus Balanus

Size variables employed in field and laboratory studies on acorn barnacles usually vary with each investigation, making accurate comparisons of results among studies difficult. The relationship of a size index to individual weight or volume is either not known, or not reported. Evaluation of 15 morphometric variables by allometric analysis, using least-squares regression, multiple step-wise regression and ANCOVA, was performed on adults of 12 species of the cosmopolitan genus Balanus. Specimens represent variation in size, shell shape, and shell design thought to occur in the genus; only isolated, complete, undamaged individuals growing on planar surfaces were used. By significance testing, within and among species, total shell volume (VTS) and basal length (LBA) increase in constant proportion with total weight, but valve weight (WTV) and soma weight (TSO) do not. Regression statistics for log-linearized data permit a discussion of other attributes which characterize these variables.     

Aspects of the biology of a population of the cosmopolitan brittlestar Amphipholis squamata (Echinodermata) from the Firth of Forth,Scotland

In the Firth of Forth, Amphipholis squamata has continuous brooding, and pulsed breeding and recruitment, with highest numbers of brooded embryos and newly released juveniles occurring in the summer months. The estimated size of maturity was 1·5 mm disc diameter although the majority of reproductive output came from individuals of between 2·00–2·99 mm disc diameter. Brittlestar size and season had significant effects on embryo production. Embryos of different developmental stages were present in the bursae of the same individual, and newly spawned embryos and those of a potentially releasable size were present each month. The majority of juveniles apparently emerge at a disc diameter of between 0·8–1·2 mm.

Brittlestars were found with full stomachs throughout the year but a peak of feeding was recorded during summer when growth and seawater temperatures were highest. Stomach analyses indicated that almost all animals (99·4%) ingest fine particulate matter but a relatively wide range of plant and animal food items was also identified. Approximately 3% of this Scottish population of A. squamata was infested by the ectoparasitic copepod Cancerilla tubulata.     

Two new free-living marine nematode species of Xyalidae (Monhysterida) from the Yellow Sea,China

Two new species of free-living marine nematodes Paramonohystera eurycephalus sp. nov. and Steineria sinica sp. nov. from the Yellow Sea, China are described. Paramonohystera eurycephalus sp. nov. is characterized by relatively wide head diameter (33 μm in width), large cup-shaped buccal cavity; presence of numerous long cervical setae; amphidial fovea 18–20 μm in diameter; spicules slender, arcuate, 3.1–3.2 anal body diameter; gubernaculum tubular with a distal hook; five to six minute precloacal supplements. Steineria sinica sp. nov. is characterized by eight groups of three subcephalic setae at almost same level as cephalic setae; eight groups of two long cervical setae situated between subcephalic setae and amphidial fovea; amphidial fovea round, 35% of corresponding body diameter, about one head diameter from anterior end; spicules slender, cephalate proximally and taper distally; gubernaculum pipe-shaped with dorsocaudal apophysis; tail conico-cylindrical with three long terminal setae.     

A revision of Eumedonus H. Milne Edwards, 1834 and Gonatonotus White, 1847 (Crustacea: Decapoda: Brachyura: Eumedonidae), two genera of crabs symbiotic with sea urchins

The eumedonid genera Eumedonus H. Milne Edwards, 1834 and Gonatonotus White, 1847, are revised. Members of both genera are obligate symbionts with sea urchins. Eumedonus is separated from Gonatonotus mainly by the presence or absence of crests on the merus of the ambulatory legs. Eumedonus, as here defined, contains five species, viz. E. niger H. Milne Edwards, 1834 (type species), E. vicinus Rathbun, 1918, E. zebra Alcock, 1895, E. brevirhynchus n. sp., and E. intermedius n. sp. Gonatonotus, as here re-diagnosed, includes three species, viz. G. pentagonus White, 1847 (type species), G. granulosus (MacGilchrist, 1905), n. comb. and G. nasutus n. sp.     

An overview of female reproductive traits in South American Mabuya (Squamata,Scincidae), with emphasis on brood size and its correlates

The viviparous New World Mabuya (Reptilia, Scincidae) are characterized by a peculiar suite of reproductive traits associated with an extreme degree of matrotrophy and a specialized placenta. We gathered information on female reproductive traits of South American Mabuya based on a compilation of literature data plus original information on two species (Mabuya dorsivittata and Mabuya macrorhyncha). Considering brood size, we identified one “large-brooded” group (brood sizes up to eight to ten) and one “small-brooded” group (brood sizes up to four to six). Brood size tended to be positively correlated with female body size among species, although the correlation is not as strong as it is within species. There were some general trends for the reproductive ecology of New World Mabuya, such as early sexual maturation, brood sizes of usually four to six young, and parturition occurring around the dry–wet season transition.     

The hermit crab Sympagurus dimorphus (Anomura: Parapaguridae) at the edge of its range in the south-western Atlantic Ocean: population and morphometry features

Sympagurus dimorphus is one of the 12 hermit crab species recorded for Argentinean waters. Despite the high abundance registered in some scallop fishing grounds, its biology remains little known. In the present study, we analysed some population features of S. dimorphus living in symbiosis with Epizoanthus paguricola from a series of samples taken in the Argentine Sea, south-western Atlantic Ocean. Our results showed that S. dimorphus was commonly found from 40ºS to lower latitudes, in a patchy distribution along the shelf-break front. The overall sex ratio was 1:1. The smallest ovigerous female measured 6 mm in cephalothoracic shield length and this size was used as parameter to define the size of juveniles. The sex ratio size class pattern corresponded to Type IV or anomalous curve. S. dimorphus is a dimorphic species, as evidenced by the larger size of the males and the positive allometric growth of the right cheliped. The species also showed asymmetry, with the left uropod always larger than the right one. To the best to our knowledge, this is the first report on population features and relative growth for a member of the genus, based on long-term sampling. This species presents a patchy distribution along the shelf-break of Argentina. Its density tended to decrease over the five-year sampling period regarding the recruitment of hermits associated with colonies of zoanthids. In addition, the relatively homogeneous nature of this refuge does not seem to influence the growth of the hermit crab, which presents sexual dimorphism in relation to the sex/size conditions.     

Biometry of brooding in seven species of amphipod (Crustacea) from the Clyde Sea area

Brood size was found to be correlated linearly with female body length in all species studied, except Ampelisca macrocephala, which is usually a single brooded species. Of the six multi-brooded species, Lembos websteri, Stegocephaloides christianiensis, Echinogammarus pirloti and Gammaropsis nitida produced small numbers of large eggs in the winter and large numbers of small eggs in the summer. In Bathyporeia pilosa larger numbers of smaller eggs were produced by the overwintering generation. In Corophium bonnellii, both maximum and minimum brood sizes were produced by the summer generation. The largest broods relative to female body size were produced by the smaller species. In L. websteri, C. bonnellii and B. pilosa mean female size was smaller in the summer than the winter generation.     

Review of the Fridericia species (Oligochaeta: Enchytraeidae) possessing two spermathecal diverticula and description of a new species

A new Fridericia species (Fridericia lacii sp. nov.) is described. Including this new species the number of valid Fridericia species with two diverticula per spermatheca is 50. The present study provides an opportunity for the comparison and separation of Fridericia species on the basis of spermatheca and diverticulum characteristics. Nine tables summarize the two larger groups and five subgroups of species possessing bidiverticulate spermathecae. The new species is distinguished from all known valid congeners in this assemblage by the following combination of traits: (1) 4–7 mm long, 200–290 µm wide (in vivo) with 30–36 segments; (2) maximum four chaetae per bundle; (3) all pairs of pharyngeal glands with ventral lobes, the third is the largest with posterior projections; (4) only three pairs of preclitellar nephridia; (5) oesophageal appendages type a; (6) mucocytes type a, lenticytes small; (7) chylus cells in preclitellar segments; (8) clitellum girdle‐shaped, glands in transverse rows, between the bursal slits only granulocytes; bursal slit is longitudinal; (9) seminal vesicle small or absent; (10) sperm funnel one‐half as long as the body diameter, collar narrower than the funnel body; (11) subneural glands absent; (12) the ampulla of the spermatheca with two sessile (or with short stalks), spherical, thin‐walled diverticula, communication with the oesophagus separate, ectal duct about as long as body diameter, one floppy ectal gland at the orifice.     

XII.—Description of a new genus and species of Cleridæ

Summary

Observations on the vertical distribution of earthworms in pasture confirm that Allolobophora longa, A. rosea and Lumbricus terrestris are relatively deep burrowers, and that the adults of these species burrow deeper than juveniles. Deep burrowing species have more elongated bodies than surface dwellers such as Dendrobaena mammalis and L. castaneus, and adults have more elongated bodies than juveniles. Long-bodied species tend to have more segments than short-bodied ones. On the limited evidence available, increase in relative thinness with age is not, apparently, associated with increased number of segments in A. rosea or L. terrestris but is in A. caliginosa and A. longa, and to a lesser extent in A. chlorotica. In adults and juveniles the diameter of the anterior region is greater than that of the posterior region of the body, and the latter is more strongly flattened dorsoventrally than the former. Such morphological differentiation is consistent with the differences in function of the anterior and posterior regions indicated by a simple model of earthworm locomotion. From the model it can be concluded that short-bodied earthworms will take relatively longer ‘steps’ when moving on the surface than will long-bodied ones, and that earthworms with relatively large anterior segments will take longer ‘steps’ than those with relatively small ones. This is in line with the results of observations on living earthworms. The mechanism of locomotion is just one of many factors influencing earthworm size and form. Others include feeding mechanics, vulnerability to predation and desiccation, and exposure to anaerobic conditions.     

Abundance variations and life history traits of two sympatric species of Neotropical annual fish (Cyprinodontiformes: Rivulidae) in temporary ponds of southern Brazil

We investigated abundance variations and life history traits (body size, sex ratio, length–weight relationships and condition factor) of two species of annual fish (Austrolebias minuano Costa and Cheffe and Cynopoecilus fulgens Costa) in temporary ponds of southern Brazil. Six samples were taken from small temporary ponds during three annual seasons over 2 years (2008–2009). A total of 104 individuals of A. minuano and 433 individuals of C. fulgens were collected. The abundance of both species tended to decrease from autumn to spring in the 2 years. The overall sex ratio of A. minuano and C. fulgens were 1.0 male to 1.8 females and 1 male to 1.04 females, respectively. Juveniles of both species occurred only in autumn over the two years and no adult was observed during this season. While the length–weight relationship of A. minuano indicated hyperallometric growth, the relationship of C. fulgens indicated values close to isometric growth.     

Review of the types of Palola (Eunicidae: Polychaeta)

As part of a review of the types of all currently known species of eunicid poly-chaetes, the genus Palola is reviewed. Nineteen named taxa are here accounted for; of these 12 are tentatively considered valid; the other species are incompletely known, or are considered synonyms of other species or are indeterminable. The number of species suggested in this paper may change once variability and allometric patterns have become better understood.     

Spatial and temporal distributions of juvenile horseshoe crabs (Arthropoda: Chelicerata) approaching extirpation along the northwestern shoreline of the New Territories of Hong Kong SAR,China

Juvenile horseshoe crabs, Tachypleus tridentatus and Carcinoscorpius rotundicauda, with prosomal widths of between 11.5 and 102.5 mm, occur along Hong Kong's northwestern shoreline abutting Deep Bay where dissolved oxygen (DO) has been identified as the principal factor determining distribution and survival. Unreported upon hitherto, however, Tachypleus tridentatus occurred consistently in association with sea-grass (Halophila beccarii) beds, with DO concentrations of 8–14 mg·L^?1, a median grain size of >180 μm, interstitial water contents of <36% (sediment wet weight) and organic contents of <3.2% (sediment dry weight). Most individuals occurred between 60 and 120 m down from the shoreline although there appeared to be a trend of down-shore migration in summer, possibly to alleviate thermal stress. No individuals were found at sediment temperatures ≤20°C, i.e. in sub-tropical Hong Kong's winter, when they adopt buried repose. Abundances of emerged T. tridentatus, peaking in November, were synchronized with interstitial salinities of 22–26‰ and averaged 1–2 individuals per 100 m². Mean population density of T. tridentatus was 4–9 individuals per 100 m². Only four individuals of C. rotundicauda were found in August and September, suggesting a recent dramatic decline in numbers. The natal crèche environment for juvenile horseshoe crabs in Hong Kong is deteriorating and threatening their survival.     

An unusual ecology among whiptails: the case of Cnemidophorus lacertoides from a restinga habitat in southern Brazil

We studied the ecology of Cnemidophorus lacertoides at a restinga habitat in southern Brazil. Peak activity occurred between 12.00 and 15.00. The mean body temperature of active lizards (35.0 ± 2.9°C) was relatively low compared with other whiptails and was significantly influenced by environmental temperatures. Mean snout–vent length and mean body mass of individuals were 56.5 mm and 4.4 g, respectively. Male and female C. lacertoides were not significantly different in body size. Cnemidophorus lacertoides consumed 12 types of prey, with ants and spiders being the most important items. Unexpectedly, lizards did not consume termites, which tend to be very important items in the diets of most whiptails. We conclude that the population of Cnemidophorus lacertoides we studied deviates from the typical whiptail ecology because many of its ecological features differ from those of most other cnemidophorines of similar size.