The effect of spine postures on the hydrodynamic drag in Epinephelus ongus larvae

Laboratory behavioural observation and computational fluid dynamics (CFD) analysis were conducted to examine whether the movement of the elongated dorsal and pelvic spines changed the hydrodynamic drag in white‐streaked grouper Epinephelus ongus larvae. The behavioural observation in the tank revealed that the larvae extended the dorsal and pelvic spines during passive transport and retracted during swimming; the angles of the dorsal and pelvic spines in relation to the anteroposterior axis were larger during the passive transport (mean ± s.d . = 28·84 ± 14·27 and 20·35 ± 15·05°) than those during the swimming (mean ± s.d . = 2·59 ± 5·55 and 0·32 ± 6·49°). The CFD analysis indicated that the relative hydrodynamic drag acting on the larvae was approximately 1·25 times higher when the spines were extended (passive transport) than when the spines were retracted (swimming), suggesting that the E. ongus larvae have an ability to adjust their hydrodynamic drag depending on the behavioural context.     

Ontogeny of form and function: locomotor morphology and drag in zebrafish (Danio rerio)

Many fish species transform in body shape during growth, but it remains unclear how this influences the mechanics of locomotion. Therefore, the present study focused on understanding how drag generation during coasting is affected by ontogenetic changes in the morphology of zebrafish (Danio rerio). The shapes of the body and fins were measured from photographs of fish ranging in size from small larvae to mature adults and these morphometrics were compared to drag coefficients calculated from high-speed video recordings of routine swimming. We found that the viscous drag coefficient of larval and juvenile fish increased by more than an order of magnitude during growth and the inertial drag coefficient decreased at a comparable rate in adults. These hydrodynamic changes occurred as zebrafish disproportionately increased the span of their fins and their body changed shape from elongated to streamlined, as reflected by the logistic growth of a newly defined streamlining index, SL. These results suggest that morphological changes incur a performance cost by generating greater drag when larvae and juveniles operate in the viscous regime, but later provide a performance benefit by reducing pressure drag in the inertial regime of the adult stage.     

Biofilm community structure and the associated drag penalties of a groomed fouling release ship hull coating

Grooming is a proactive method to keep a ship’s hull free of fouling. This approach uses a frequent and gentle wiping of the hull surface to prevent the recruitment of fouling organisms. A study was designed to compare the community composition and the drag associated with biofilms formed on a groomed and ungroomed fouling release coating. The groomed biofilms were dominated by members of the Gammaproteobacteria and Alphaproteobacteria as well the diatoms Navicula, Gomphonemopsis, Cocconeis, and Amphora. Ungroomed biofilms were characterized by Phyllobacteriaceae, Xenococcaceae, Rhodobacteraceae, and the pennate diatoms Cyclophora, Cocconeis, and Amphora. The drag forces associated with a groomed biofilm (0.75 ± 0.09 N) were significantly less than the ungroomed biofilm (1.09 ± 0.06 N). Knowledge gained from this study has helped the design of additional testing which will improve grooming tool design, minimizing the growth of biofilms and thus lowering the frictional drag forces associated with groomed surfaces.     

Behavioral impacts of disentanglement of a right whale under sedation and the energetic cost of entanglement

Protracted entanglement in fishing gear often leads to emaciation through reduced mobility and foraging ability, and energy budget depletion from the added drag of towing gear for months or years. We examined changes in kinematics of a tagged entangled North Atlantic right whale (Eg 3911), before, during, and after disentanglement on 15 January 2011. To calculate the additional drag forces and energetic demand associated with various gear configurations, we towed three sets of gear attached to a load‐cell tensiometer at multiple speeds. Tag analyses revealed significant increases in dive depth and duration; ascent, descent and fluke stroke rates; and decreases in root mean square fluke amplitude (a proxy for thrust) following disentanglement. Conservative drag coefficients while entangled in all gear configurations (mean ± SD C_d,e,go = 3.4 × 10^?3 ± 0.0003, C_d,e,gb = 3.7 × 10^?3 ± 0.0003, C_d,e,sl = 3.8 × 10^?3 ± 0.0004) were significantly greater than in the nonentangled case (C_d,n = 3.2 × 10^?3 ± 0.0003; P = 0.0156, 0.0312, 0.0078, respectively). Increases in total power input (including standard metabolism) over the nonentangled condition ranged from 1.6% to 120.9% for all gear configurations tested; locomotory power requirements increased 60.0%–164.6%. These results highlight significant alteration to swimming patterns, and the magnitude of energy depletion in a chronically entangled whale.     

Endogenous activity rhythm in Talitrus saltator,Britorchestia brito (Crustacea,Amphipoda) and Tylos europaeus (Crustacea,Isopoda) from Barkoukech Beach (Tabarka,Tunisia)

The locomotor activity rhythm of three supralittoral crustacean species, Tylos europaeus (terrestrial isopod) and Britorchestia brito and Talitrus saltator (amphipod, Talitridea), was investigated in Barkoukech Beach. The rhythm was monitored in individual animals in spring under continuous darkness and constant temperature. Results revealed that whatever the species, actograms and mean activity curves showed that specimens of T. europaeus and T. saltator concentrated their activity during the subjective night; whereas, B. brito concentrated its activity during the subjective day. The three species exhibited a circadian locomotor rhythm with mean circadian period, respectively, equal to 24h41′ ± 0h44′, 24h46′ ± 0h55′ and 25h21′ ± 1h16′. The most stable locomotor rhythm was found in T. saltator (0.444 ± 0.246). Furthermore, individuals of T. europaeus were significantly more active (10h47′ ± 2h52′) than the two amphipods. Differences in the activity patterns of the three species will be discussed as an adaptative strategy to respond to interspecific competitive interactions.     

Asian small-clawed otters (Amblonyx cinerea): resting and swimming metabolic rates

Open-flow oxygen and carbon dioxide respirometry was used in Neumünster Zoo (Germany) to examine the energy requirements of six Asian small-clawed otters (Amblonyx cinerea) at rest and swimming voluntarily under water. Our aim was to compare their energy requirements with those of other warm-blooded species to elucidate scale effects and to test whether the least aquatic of the three otter species differs markedly from these and its larger relatives. While at rest on land (16 °C, n = 26), otters (n = 6, mean body mass 3.1 ± 0.4 kg) had a respiratory quotient of 0.77 and a resting metabolic rate of 5.0 ± 0.8 Wkg⁻¹(SD). This increased to 9.1 ± 0.8 Wkg⁻¹ during rest in water (11–15 °C, n = 4) and to 17.6 ± 1.4 Wkg⁻¹ during foraging and feeding activities in a channel (12 °C, n = 5). While swimming under water (n = 620 measurements) in an 11-m long channel, otters preferred a speed range between 0.7 ms⁻¹ and 1.2 ms⁻¹. Transport costs were minimal at 1 ms⁻¹ and amounted to 1.47 ± 0.24 JN⁻¹ m⁻¹ (n = 213). Metabolic rates of small-clawed otters in air were similar to those of larger otter species, and about double those of terrestrial mammals of comparable size. In water, metabolic rates during rest and swimming were larger than those extrapolated from larger otter species and submerged swimming homeotherms. This is attributed to high thermoregulatory costs, and high body drag at low Reynolds numbers. Accepted: 21 December 1998     

How many times has polyploidization occurred during acipenserid evolution? New data on the karyotypes of sturgeons (Acipenseridae,Actinopterygii) from the Russian Far East

The karyology of species of sturgeon from the Russian Far East demonstrates that the karyotype of the Sakhalin sturgeon (Acipenser mikadoi) includes 262 ± 4 chromosomes with 80 biarmed chromosomes and the number of chromosome arms (NF) 342 ± 4, the karyotype of the Amur sturgeon (A. schrenckii) includes 266 ± 4 chromosomes with 92 biarmed chromosomes and NF 358 ± 4, and the karyotype of the kaluga (A. dauricus) consists of 268 ± 4 chromosomes with 100 biarmed chromosomes and NF 368 ± 4. These results prove that all western Pacific sturgeon species are from a tetraploid origin, based on a recent ploidy scale. This suggests that at least three polyploidization events have occurred during the evolution of Acipenseridae. However, if polyploid species originated by hybridization between diploid species, there may have been more polyploidization events in this group of fishes.     

Water and carbon storage capacity in Isolatocereus dumortieri (Cactaceae) in an intertropical semiarid zone in Mexico

In the biosphere reserve Barranca de Metztitlán in Mexico, there is an extensive area with a semiarid scrub. The dominant species is the cactus Isolatocereus dumortieri. This is a key species in the ecosystem, because many species of birds, bats and insects are feeding from its nectar, pollen and fruits during the dry season thanks to their capacity to store water and carbon. However, there is no information about their potential to store water and carbon. The purpose of this study was to estimate the ability of I. dumortieri to store water and carbon. Water content per plant was estimated as 537.64 ± 71.59 L during the dry season and 692.24 ± 92.18 L during the wet season. In the same way the carbon stored per cactus was 16.75 kg ± 7.07 corresponding to 1.25 kg C m². The results shows the importance of I. dumortieri in maintaining the ecosystem services of the scrub vegetation.     

Phenology of Sargassum spp. in Tung Ping Chau Marine Park, Hong Kong SAR, China

Eight species of the brown alga Sargassum have been recorded from Tung Ping Chau Marine Park in Hong Kong and the phenology of four of these was monitored from 1996 to 2000. All four species followed a typical growth cycle of Sargassum species reported elsewhere but with some annual variations. For S. hemiphyllum, the maximum mean (±SD) plant length, ranging from 38.5 ± 10.5 to 61.9 ± 19.9 cm, was recorded in January to March. The peak reproductive season was also mainly in February to March with up to 89% of the plants being reproductive. Some plants, however, remained reproductive until May. For. S. henslowianum, the maximum mean plant length, ranging from 45.5 ± 25.5 to 77 ± 24.8 cm, was recorded mainly in November to January. The peak reproductive season was in November to February with up to 100% of the plants being reproductive. For S. siliquastrum, the maximum mean plant length, ranging from 48.2 ± 29.9 to 63.4 ± 22.1 cm, was also recorded mainly in January. The reproductive plants were found mainly between late December and mid February with up to 98% of the plants being reproductive. For. S. patens, the maximum mean plant length ranging from 87.6 ± 62.4 to 118.7 ± 41.3 cm was recorded in January to March. Reproduction of this species was not monitored. Changes in water temperature over seasons were likely to be critical in affecting the phenological patterns of these species.     

Role of six European tree species and land‐use legacy for nitrogen and water budgets in forests

Water and nutrient fluxes for single stands of different tree species have been reported in numerous studies, but comparative studies of nutrient and hydrological budgets of common European deciduous tree species are rare. Annual fluxes of water and inorganic nitrogen (N) were established in a 30‐year‐old common garden design with stands of common ash (Fraxinus excelsior), European beech (Fagus sylvatica L.), pedunculate oak (Quercus robur), small‐leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus) and Norway spruce (Picea abies [L.] Karst.) replicated at two sites in Denmark, Mattrup and Vallø during 2 years. Mean annual percolation below the root zone (mm yr^?1±SE, n=4) ranked in the following order: maple (351±38)>lime (284±32), oak (271±25), beech (257±30), ash (307±69)? spruce (75±24). There were few significant tree species effects on N fluxes. However, the annual mean N throughfall flux (kg N ha^?1 yr^?1±SE, n=4) for spruce (28±2) was significantly larger than for maple (12±1), beech (11±1) and oak (9±1) stands but not different from that of lime (15±3). Ash had a low mean annual inorganic N throughfall deposition of 9.1 kg ha^?1, but was only present at Mattrup. Annual mean of inorganic N leaching (kg ha^?1 yr^?1±SE, n=4) did not differ significantly between species despite of contrasting tree species mean values; beech (25±9)>oak (16±10), spruce (15±8), lime (14±8)? maple (1.9±1), ash (2.0±1). The two sites had similar throughfall N fluxes, whereas the annual leaching of N was significantly higher at Mattrup than at Vallø. Accordingly, the sites differed in soil properties in relation to rates and dynamics of N cycling. We conclude that tree species affect the N cycle differently but the legacy of land use exerted a dominant control on the N cycle within the short‐term perspective (30 years) of these stands.     

Phycoremediation resultant lipid production and antioxidant changes in green microalgae Chlorella Sp.

In this investigation, we report on the treatment of tannery wastewater using microalgae Chlorella species to produce lipid and fatty acid as well as changes in antioxidant metabolism during the treatment. The variation in growth, production of pigments, antioxidant metabolism, lipid and fatty acids, and nutrient removal from wastewater during the remediation were observed. Surprisingly, a profuse growth was found in 50% diluted tannery wastewater (TW), which supported to accumulate high yield of lipid (18.5%) and unsaturated fatty acids (50.05%). The antioxidant activity of microalgae in both the concentrations (50% and 100% TW) were viz., lipid peroxidation 1.6 ± 0.1 and 2.3 ± 0.02nmol MDA mg^?1 protein, SOD 10.3 ± 0.4 and 15.7 ± 0.9 U mg^?1 protein, CAT 0.17 ± 0.036 and 0.52 ± 0.06 U mg^?1 protein, and APX 7.2 ± 0.8 and 11.2 ± 09 U mg^?1 protein respectively, which point out that the free radical scavenging mechanism against heavy metal stress. Maximum phycoremediation of heavy metals observed from both concentrations during the healthy growth period were Cr – 73.1, 45.7%, Cu – 90.4, 78.1%, Pb – 92.1, 52.2%, and Zn – 81.2, 44.6%, respectively. This study proved the potential use of Chlorella for heavy metal and nutrient removal from tannery wastewater. Moreover, an unaffected growth with high antioxidant activity of this species promises a sustainable lipid and fatty acid contents for biofuel production.     

DISTRIBUTION OF INTRACELLULAR NITROGEN IN MARINE MICROALGAE: BASIS FOR THE CALCULATION OF SPECIFIC NITROGEN-TO-PROTEIN CONVERSION FACTORS

The utilization of nitrogen-to-protein conversion factors (N-Prot factors) is a widely accepted and practical way to determine total protein content. The accuracy of protein determination depends on the establishment of specific N-Prot factors, since the conventional factor of 6.25 may be unsuitable for all species. This study was designed to determine the concentrations of the main nitrogenous compounds and to establish N-Prot factors specific for the following marine microalgae: Chlorella minutissima, Dunaliella tertiolecta, Hillea sp., Isochrysis galbana, Nannochloropsis oculata, Phaeodactylum tricornutum, Prorocentrum minimum, Skeletonema costatum, Synechococcus subsalsus, and Tetraselmis gracilis. Cultures were maintained under a 12-h photoperiod (300 μmol photons·m^?2·s^?1) at temperatures of 20.0°± 1.0° C (dark) to 23.0°± 2.0° C (light) in Walne’s culture medium without additional external carbon sources. The distribution of intracellular nitrogen was studied by determining total nitrogen (TN, by CHN [carbon, hydrogen, and nitrogen] analysis), protein N (PN, by analysis of total amino acids), and nonprotein N (NPN, determined by analysis of DNA, RNA, chlorophylls (chl) a,b, and c, and intracellular inorganic nitrogen—NO₃^?, NO₂^?, and NH₃+ NH₄⁺) in logarithmic and stationary growth phases of cultures. Variations occurred in both accumulation and distribution of PN and NPN among the species, as well as in each species during the different growth phases. Inorganic nitrogen compounds were observed to be the most important NPN source (from 6.4 ± 0.1% to 41.8 ± 4.2% of total N) in all species (except D. tertiolecta), followed by nucleic acids (from 0.8 ± 0.1% to 26.1 ± 2.4% of TN) and chlorophylls (from 0.2 ± 0.0% to 3.1 ± 0.3% of TN). Total amino acid residues ranged from 63.1 ± 4.6% up to 88.1 ± 11.2% of TN, which is in agreement with the presence of high NPN concentrations. N-Prot factors are proposed for each growth phase in the studied species, based on the ratio of amino acid residues to TN, establishing specific N-prot factors ranging from 3.60 ± 0.27 to 4.99 ± 0.64. The mean N-Prot factor for all species/growth phases was 4.58 ± 0.11. The present study shows that the use of the traditional factor 6.25 is not suitable for these marine microalgae, and possibly for other species, because it overestimates their actual protein content.     

Variation in True Metabolizable Energy Among Aquatic Vegetation and Ducks

Avian diet quality is typically measured using true metabolizable energy (TME_N), which is a measure of assimilable energy of food items accounting for innate endogenous losses. Originally developed for use in the poultry industry, TME_N methods have been adapted to determine the value of natural foods consumed by waterfowl to parameterize bioenergetics models for conservation planning. Because there is little knowledge of the variation in TME_N estimates among food items and waterfowl species, we investigated TME_N of 6 common species of submersed aquatic vegetation for mallards (Anas platyrhynchos; i.e., a diet generalist) and gadwall (Mareca strepera; i.e., a diet specialist) in the midwestern United States during autumn 2015–2017. We precision fed and collected excreta from ducks using standard bioassays to estimate TME_N. Mallards had slightly greater TME_N than gadwall, but there was considerable variation in TME_N among vegetation species, duck species, and individuals within each species. True metabolizable energy (±SE; kcal/g[dry]) for mallards was greatest for Canadian waterweed (Elodea canadensis; 1.66 ± 0.26), followed by coontail (Ceratophyllum demersum; 1.51 ± 0.28), southern naiad (Najas guadalupensis; 1.37 ± 0.39), sago pondweed (Stuckenia pectinata; 0.50 ± 0.22), wild celery (Vallisneria americana; 0.05 ± 0.42), and Eurasian watermilfoil (Myriophyllum spicatum; –0.13 ± 0.42). Mean TME_N for gadwall was greatest for Eurasian watermilfoil (0.77 ± 0.32), followed by Canadian waterweed (0.70 ± 0.31), coontail (0.55 ± 0.28), southern naiad (–0.61 ± 0.34), wild celery (–0.98 ± 0.39), and sago pondweed (–1.07 ± 0.33). Generally, TME_N for most vegetation species was less than agricultural grains, but it was similar to ranges reported for seeds of naturally occurring hydrophytic vegetation and aquatic macroinvertebrates. We recommend that conservation planners incorporate species-specific TME_N estimates in bioenergetics models and that future researchers improve TME_N assays for wild waterfowl following our recommendations. © 2020 The Wildlife Society.     

Isolation and characterization of microsatellite loci from three cryptic species of Ceratosolen emarginatus

From an enriched (AG)_n/(AC)_n library, we developed nine polymorphic microsatellite loci for three cryptic species of the fig‐pollinating wasp Ceratosolen emarginatus. We genotyped one population for each of the three cryptic species across all the nine loci. In total, 204 alleles were detected from the three cryptic species of C. emarginatus. The observed heterozygosity was 0.755 ± 0.034, 0.653 ± 0.030 and 0.603 ± 0.073 in C. emarginatus populations A, B and C, respectively; the expected heterozygosity was 0.850 ± 0.031, 0.724 ± 0.035 and 0.702 ± 0.104, respectively. No linkage disequilibrium was found between any two loci of all three cryptic species. The newly isolated microsatellite markers will be very useful for estimating the genetic variation within and among the cryptic species and for revealing the mechanisms of speciation and inbreeding coexistence hypothesis of the cryptic species.     

Survival and fecundity of Dichroplus maculipennis and Ronderosia bergi (Orthoptera: Acrididae: Melanoplinae) following infection by Beauveria bassiana (Ascomycota: Hypocreales) under laboratory conditions

This study examined the effects of strain Beauveria bassiana (LPSC 1067) on nymphal development time, fecundity and adult survival in Dichroplus maculipennis and Ronderosia bergi under laboratory conditions. It was observed that infection with 1×10³ conidia/ml altered nymphal development time, fecundity and adult survival in both species. Mortality of D. maculipennis during third through the last instar (sixth) was significantly higher among treated nymphs (66±3.8%) than in controls (15±1.7%). Similarly, mortality in R. bergi during third through the last instar (fifth) was higher in treated nymphs (71±2.8%) than in controls (19±1.5%). Nymphal development times of both infected D. maculipennis and R. bergi were longer than controls. On the other hand, among survivors of both the species, control adults lived longer than infected adults. Finally, control grasshoppers of both species were much more successful reproductively than infected grasshoppers.     

Upper thermal tolerance of closely related Danio species

The main finding of this study was that measuring maximum heart rate during incremental warming was an effective tool to estimate upper thermal limits in three small cyprinid Danio species, which differed significantly. Arrhenius breakpoint temperature for maximum heart rate, purportedly an index of optimum temperature, was 21·2 ± 0·4, 20·1 ± 0·4 and 18·9 ± 0·8° C (mean ± s.e .) for zebrafish Danio rerio, pearl danio Danio albolineatus and glowlight danio Danio choprae, respectively. The temperature where cardiac arrhythmias were first induced during warming (T_arr) was 36·6 ± 0·7, 36·9 ± 0·8 and 33·2 ± 0·8° C (mean ± s.e .) and critical thermal maximum (T_Cm) was 39·9 ± 0·1, 38·9 ± 0·1 and 37·2 ± 0·1° C (mean ± s.e .) for D. rerio, D. albolineatus and D. choprae, respectively. The finding that T_arr was consistently 3–4° C lower than T_Cm suggests that collapse of the cardiac life support system may be a critical trigger for upper temperature tolerance. The upper thermal limits established here, which correlate well with a broad natural environmental temperature range for D. rerio and a narrow one for D. choprae, suggest that upper thermal tolerance may be a genetic trait even among closely related species acclimated to common temperatures.     

Field observations quantifying attraction of four tortricid moths to high-dosage pheromone dispensers in untreated and pheromone-treated orchards

Orientational responses of four species of feral tortricid moths (Lepidoptera: Tortricidae) to polyethylene tube dispensers of pheromone were observed in a 0.8 ha apple orchard treated with such pheromone dispensers and in an untreated 0.8 ha orchard. Male oblique‐banded leafrollers, Choristoneura rosaceana (Walker) (mean 7.2 ± 0.4 moths/night during 21 nights), Oriental fruit moths, Grapholita molesta (Busck) (mean 10.5 ± 2.1 during 20 evenings), and the redbanded leafrollers, Argyrotaenia velutinana (Walker) (mean 2.0 ± 1.1 during 14 nights) were observed approaching within 100 cm of their respective polyethylene‐tube pheromone dispensers in the untreated orchard. Furthermore, C. rosaceana (mean 2.0 ± 0.7 during 17 nights) and G. molesta (mean 1.5 ± 0.4 over 20 evenings) came within 100 cm of their respective polyethylene‐tube pheromone dispensers in the pheromone‐treated orchard. Most visits lasted less than 10 s, after which the majority of moths departed by flying upwind. In the untreated orchard, the number of C. rosaceana observed orienting to polyethylene tube dispensers was greater than the number captured in optimized monitoring traps (1.9 ± 0.4) per night of observation. The numbers of A. velutinana (2.0 ± 1.1) or G. molesta (10.5 ± 2.1) attracted to polyethylene‐tube dispensers in the untreated orchard did not differ statistically from the numbers captured in optimized monitoring traps per night of observation. In the pheromone‐treated orchard, the number of C. rosaceana (2.0 ± 0.4) or G. molesta (1.2 ± 0.2) observed orienting to polyethylene‐tube dispensers did not differ statistically from the numbers of male moths of these species captured in optimized monitoring traps per night of observation. No codling moths, Cydia pomonella L. were observed orienting to, or landing near, their respective polyethylene‐tube dispensers in either the untreated or pheromone‐treated orchards, although substantial numbers were captured in monitoring traps per night of observation (6.0 ± 1.7) in the untreated orchard. The attraction of male moths to polyethylene tube dispensers thus occurred in three of the four species observed. These results provide support for the idea that false‐plume‐following is an important component of the mechanisms mediating communicational disruption in moths by polyethylene‐tube dispensers.     

Reconciliation in captive cotton‐top tamarins (Saguinus oedipus), a cooperative breeding primate

Reconciliation has been demonstrated in all primate species in which the phenomenon has been studied. However, reconciliation has been studied in only two species of callitrichids, and conclusions remain controversial. The first aim of this study has been to find out whether captive cotton‐top tamarins (Saguinus oedipus) reconcile, since this is the first such study on this species. We examined 227 conflicts in three family groups (N=19). Instances in which individuals remained together in t=0 (29; 12.8%) were not analyzed. The cotton‐top tamarins showed heightened affiliation between opponents in the postconflict periods (PC) compared with matched control (MC) periods (39.88±5.12% and 3.18±1.27%, respectively), with a corrected conciliatory tendency of 37.17±5.37%, and a “time window” that included the first 180 sec of the PC period. Former opponents were the most likely recipient of affiliative behaviors during the PC periods: 39.83±4.26% vs. 11.36±5.33% during MC periods. The proportion of attracted pairs (47.13±6.25%) was significantly higher than those of dispersed pairs for male–male conflicts (3.79±1.79), but not for male–female conflicts (27.31±9.32 and 4.82±2.9, respectively). In cooperative‐breeding species, specific sex‐class dyads might differ in how they resolve conflicts. Am. J. Primatol. 71:895–900, 2009. © 2009 Wiley‐Liss, Inc.     

Preliminary observations on fecundity of the processid shrimp Nikoides schmitti (Decapoda,Caridea) from Mexican Caribbean

Nikoides schmitti is widely distributed along the Atlantic coast of the Americas, from North Carolina to Bahia, Brazil and Cuba and Guadeloupe; however, the knowledge about their reproductive biology is poorly known. In this study, data such as sex ratio, fecundity, size and volume of the embryos, and brood loss of material collected in July 1997 from Mahahual, Quintana Roo, Mexico is provided. The sample of 728 specimens had a sex ratio of 0.40 males per female. Fecundity (N = 31) of ovigerous females (Stage I) varied from 219 to 817, with an average of 432 ± 177 embryos. The newly extruded embryos of N. schmitti were small (0.41 ± 0.030 mm) and similar in size to those reported for other species of the genus. The mean volume of the embryos changed significantly during development, increasing 60.9% from stages I to III. Embryo loss during incubation was estimated in 32.9%. This study provides baseline information about the reproduction of N. schmitti and contributes to a better knowledge of this species little studied.     

The abundance and diversity of Odonata along an altitudinal gradient in East Java,Indonesia

Odonate diversity in East Java was surveyed, and samplings were made during 2 years in ten sites along an altitudinal gradient. The characteristics of odonate assemblages in East Java were analyzed regarding of the number of individuals, the number of species, and Shannon's diversity index. The differences in abundance, species richness, and diversity between study sites were analyzed by an independent t‐test. There were 3270 individuals of Odonata belong to 30 species, 7 families and 2 suborders identified from all study sites. The abundance, species richness and diversity of Odonata varied between study sites. The greatest abundance of Odonata was found in Malang Coban Talun (MCT) (148.8 ± 9.5), while the lowest was in South Beach Forest (SBF) (14.4 ± 3.6). The highest species richness and diversity was found in Malang Paddy Field (MPF) (richness =14.4 ± 0.8 and H′ = 2.4 ± 0.1), while the lowest was found in South Coastal Area (SCA) (richness =2.8 ± 0.1 and H′ = 0.4 ± 0.1). A significant positive correlation was detected between the elevation and overall odonate abundance (P < 0.05), while there was not significant correlation between that and odonate species richness and diversity.