Foliar limonene uptake scales positively with leaf lipid content: "non-emitting" species absorb and release monoterpenes

Monoterpenes synthesized and released by emitting vegetation can be taken up by neighboring non-emitting plants, but the uptake capacity of non-emitting species has not been studied extensively. We investigated the foliar uptake potential of the hydrophobic monoterpene limonene in 13 species of contrasting leaf structure and lipid content to determine the structural and chemical controls of monoterpene uptake. Leaf dry mass per unit area (M(A,D)) varied 6.5-fold, dry to fresh mass ratio (D(F)) 2.7-fold, lipid content per dry mass (L(M)) 2.5-fold and per unit area (L(A)) 4.6-fold across the studied species. Average foliar limonene uptake rate (U(A)) from air at saturating limonene partial pressures varied from 0.9 to 6 nmol m(-2) s(-1), and limonene leaf to air partition coefficient (K(FA), ratio of limonene content per dry mass to limonene partial pressure) from 0.7 to 6.8 micromol kg(-1) Pa(-1). U(A) and K(FA) scaled positively with leaf lipid content, and were independent of D(F), indicating that variation in leaf lipid content was the primary determinant of species differences in monoterpene uptake rate and K(FA). Mass-based limonene uptake rates further suggested that thinner leaves with greater surface area per unit dry mass have higher uptake rates. In addition, limonene lipid to air partition coefficient (K(LA)=K(FA)/L(M)) varied 19-fold, indicating large differences in limonene uptake capacity at common leaf lipid content. We suggest that the significant uptake of hydrophobic monoterpenes when monoterpene ambient air concentration is high and release when the concentration is low should be included in large-scale monoterpene emission models.     

Feeding pattern and the visual light environment in myctophid fish larvae

The trophic spectrum and feeding pattern of two myctophid larvae, Benthosema glaciale and Myctophum punctatum , were analysed in relation to changes in daily light intensity. The larvae of both species live relatively deep, occurring in the first 100 m, though distribution of M. punctatum extends to 150 m depth. The present study, carried out in the western Mediterranean (Alboran Sea), indicated that the larvae of the two species exhibit different foraging strategies. Both started to feed at dawn, but while feeding of M. punctatum was high at dawn and dusk, the feeding of B. glaciale remained high throughout the day. The light intensity profiles taken during the day indicated that at the depths where the species dwelt, light intensity was enough to provoke a feeding response. The larvae of these species, in contrast to the majority of fish larvae, had an enhanced sensitivity due to their pure rod‐like retina, an adaptation for foraging at low light intensities. Both species showed an ontogenetic change in their diet: B. glaciale preflexion larvae fed mainly on copepod eggs and nauplii, while postflexion larvae consumed calanoid copepodites; M. punctatum larvae showed a more diversified diet, composed of larger prey items. The stalked and elongated eye of M. punctatum larvae would enable the detection of a greater range of prey in terms of shape and size. In addition, the retina of this species was characterized by a higher summation ratio and longer photoreceptors, indicating a preference for dimmer environments. This could explain the decreasing feeding activity of M. punctatum during the high light intensity of the middle daylight hours. As a clear relationship existed between feeding pattern and light intensity in these myctophid larvae, the visual characteristics of each species could help to explain the different strategies of foraging behaviour, therefore avoiding a possible overlap in their trophic niche.     

Trade-off between cadmium tolerance and relative growth rate in 10 grass species

Plant species exhibit great differences in heavy metal accumulation and tolerance. In this study we compared interspecific differences in responses to Cadmium (Cd) stress among 10 C₃ grass species by growing hydroponically under the conditions of different Cd treatments (0, 5, 10 and 50 μM). Responses of plant shoot dry mass to Cd treatments (resistance) were separated into avoidance (the response of shoot Cd concentration to Cd treatments) and tolerance (the response of shoot dry mass to shoot Cd concentration). The relative growth rate (RGR) and leaf structural properties of plants were measured under optimum growth condition. There were large differences in resistance, avoidance and tolerance among the species. Avoidance and tolerance were attributed independently to total Cd resistance. Resistance and tolerance were correlated negatively with RGR, leaf water content (LW), specific leaf area (SLA), leaf elongation rate (LER), and leaf length (LL), but the leaf dry matter concentration (LMDC), and nuclear DNA content showed a positive correlation with resistance and tolerance. These results indicate a trade-off between growth rate and tolerance to Cd stress. Species with higher Ca/Mg ratios showed low avoidance (r = −0.943***), suggesting uptake inhibition by Ca²⁺ to develop avoidance against Cd stress.     

Higher productivity at the cost of increased host-specificity when Maculinea butterfly larvae exploit ant colonies through trophallaxis rather than by predation

Abstract .1. Field studies were made of the benefits and costs of two feeding strategies in the genus Maculinea, whose final-instar larvae parasitise Myrmica ant colonies. Maculinea arion is an obligate predator of ant brood, whereas M. rebeli and M. alcon mimic ant larvae and are fed (like cuckoos) directly by the workers.
2. Samples of > 1500 Myrmica nests confirmed laboratory-based predictions that, by feeding at a lower trophic level, many (4.7-fold) more individuals of M. rebeli and M. alcon are supported per ant colony than M. arion.
3. Because of their efficient feeding, cuckoo species often occupied sites where their phytophagous early larval populations coincided to only a small extent (> 10%) with host Myrmica colonies, whereas all sites supporting M. arion had 50–100% of the phytophagous stages within foraging range of the host Myrmica species.
4. Greater host-specificity was identified as another consequence of cuckoo-feeding. The ecological cost of this is discussed .
5. The feeding of other Maculinea species had not been fully described: the data suggest that M. nausithous is a predator of ant brood and confirm that M. teleius is predacious .     

武汉东湖桡足类生物量及生产量的初步研究

本文主要论述1980—1982年武汉东湖桡足类生物量及生产量的测算结果。三周年来在东湖Ⅰ、Ⅱ采样站上共观察到5种剑水蚤:广布中剑水蚤(Mesocyclops leuckarti)、近邻剑水蚤(Cyclops vicinus vicinus)、透明温剑水蚤(Thermocyclops hyalinus)、台湾温剑水蚤(Thermocyclops taihokuensis)、锯缘真剑水蚤(Eucyclops serrulatus)和5种哲水蚤:球状许水蚤(Schmackeria forbesi)特异荡镖水蚤(Neutrodiaptomus incongruens)、右突新鏢水蚤(Neodiaptomus schmackeria)、中华原鏢水蚤(Eodiaptomus sinensis)、汤匙华哲水蚤(Sinocalanus dorrii)。其总年平均生物量为321.74毫克干重/平方米。其中剑水蚤为194.70毫克干重/平方米,占60.51%;哲水蚤为127.04毫克干重/平方米,占39.49%。总年生产量为16.959克干重/平方米。其中剑水蚤为11.225克干重/平方米,占66.19%;哲水蚤为5.734克干重/平方米,占33.81%。年P/B比为52.55;其中剑水蚤为57.63,哲水蚤为46.02。各发育阶段的年平均生物量以桡足幼体最高,其次为无节幼体,卵最低。年生产量则以无节幼体最高,其次为桡足幼体,卵最低。从各种类所占总年平均生物量、年生产量的百分比值来看,广布中剑水蚤的比值最大,其次为球状许水蚤、近邻剑水蚤和特异荡鏢水蚤。       

Nuclear DNA,nuclear area and nuclear dry mass in thirteen species of Crotalaria (Angiospermae,Leguminosae)

Estimations on nuclear DNA content, nuclear area and nuclear dry mass were made on 13 species of Crotalaria, with the help of Vicker's M 85 microdensitometer and Vicker's interferometer. Highly significant differences for all three characters were found between species. DNA density (DNA/area) increased with increase in DNA content. The cultivated species, C. juncea had a lower DNA density relative to its DNA content.—Nuclear DNA made only a small fraction of nuclear dry mass (115). Although total dry mass and non-nucleolar nuclear dry mass showed significant regression on DNA content, the nucleolar dry mass gave a much wider scatter, indicating that nucleolar mass is not equally dependent on nuclear DNA content.     

Changes in biomass and chemical composition during lecithotrophic larval development of the southern king crab, Lithodes santolla (Molina)

Changes in biomass and elemental composition (dry mass, W; carbon, C; nitrogen, N; hydrogen, H) were studied in the laboratory during complete larval and early juvenile development of the southern king crab, Lithodes santolla (Molina), formerly known as Lithodes antarcticus (Jacquinot). At 6±0.5 °C, total larval development from hatching to metamorphosis lasted about 10 weeks, comprising three demersal zoeal stages and a benthic megalopa, with mean stage durations of 4, 7, 11 and 47 days, respectively. No differences in development duration or mortality were observed in larvae either fed with Artemia sp. nauplii or unfed, indicating that all larval stages of L. santolla are lecithotrophic. First feeding and growth were consistently observed immediately after metamorphosis to the first juvenile crab stage. Regardless of the presence or absence of food, W, C, N and H decreased throughout larval development. Also the C:N mass ratio decreased significantly, from 7.7 at hatching to 4.1 at metamorphosis, indicating that a large initial lipid store remaining from the egg yolk was gradually utilized as an internal energy source, while proteins played a minor role as a metabolic substrate. In total, 56-58% of the initial quantities of C and H present at hatching, and 20% of N were lost during nonfeeding larval development to metamorphosis. Nine to ten percent of the initially present C, N and H were lost with larval exuviae, half of these losses occurring in the three zoeal stages combined and another half in the megalopa stage alone. Metabolic biomass degradation accounted for losses of about 47-50% in C and H but for only 10% in N. Hence, most of the losses in C and H reflected metabolic energy consumption (primarily lipid degradation), while about half of the losses in N and two thirds of those in W were due to larval exuviation. Complete independence from food throughout larval development is based on an enhanced maternal energy investment per offspring and on energy-saving mechanisms such as low larval locomotory activity and low exuvial losses. These traits are interpreted as bioenergetic adaptations to food-limited conditions in Subantarctic regions, where a pronounced seasonality of day length limits the period of primary production, while low temperatures enforce a long duration of pelagic development.     

Influences of salinity on the physiology and distribution of the Arctic coralline algae,Lithothamnion glaciale (Corallinales,Rhodophyta)

In Greenland, free‐living red coralline algae contribute to and dominate marine habitats along the coastline. Lithothamnion glaciale dominates coralline algae beds in many regions of the Arctic, but never in Godthåbsfjord, Greenland, where Clathromorphum sp. is dominant. To investigate environmental impacts on coralline algae distribution, calcification and primary productivity were measured in situ during summers of 2015 and 2016, and annual patterns of productivity in L. glaciale were monitored in laboratory‐based mesocosm experiments where temperature and salinity were manipulated to mimic high glacial melt. The results of field and cold‐room measurements indicate that both L. glaciale and Clathromorphum sp. had low calcification and photosynthetic rates during the Greenland summer (2015 and 2016), with maximum of 1.225 ± 0.17 or 0.002 ± 0.023 μmol CaCO ₃ · g^?1 · h^?1 and ?0.007 ±0.003 or ?0.004 ± 0.001 mg O₂ · L^?1 · h^?1 in each species respectively. Mesocosm experiments indicate L. glaciale is a seasonal responder; photosynthetic and calcification rates increase with annual light cycles. Furthermore, metabolic processes in L. glaciale were negatively influenced by low salinity; positive growth rates only occurred in marine treatments where individuals accumulated an average of 1.85 ± 1.73 mg · d^?1 of biomass through summer. These results indicate high freshwater input to the Godthåbsfjord region may drive the low abundance of L . glaciale , and could decrease species distribution as climate change increases freshwater input to the Arctic marine system via enhanced ice sheet runoff and glacier calving.     

Digestive proteinases of red shrimp Pleoticus muelleri (Decapoda, Penaeoidea): partial characterization and relationship with molting

The present study describes the activity and some characteristics of proteinases in the hepatopancreas of red shrimp Pleoticus muelleri during the different stages of the molting cycle. Proteolytic activity was highest between pH 7.5 and 8. The hepatopancreatic protein content in the premolt stage was higher than in the other stages of the molting cycle (P<0.05). No significant differences were found in total proteolytic activity in the hepatopancreas when comparing molting stages. The proteolytic activity of the P. muelleri hepatopancreas enzyme preparations is the main responsibility of serine proteinases. TLCK, a trypsin inhibitor, reduced azocasein hydrolysis between 26% (intermolt) and 37% (premolt). TPCK, a chymotrypsin inhibitor, did not decrease hydrolytic activity, except for in postmolt. Low trypsin and chymotrypsin activities were found during intermolt, and increased in postmolt. The electrophoretogram of the enzyme extracts shows 12 bands of activity during intermolt (from 16.6 to 53.1 kDa). Some fractions were not detected in the postmolt and premolt stages. Three low molecular weight trypsin forms (17.4, 19.1 and 20 kDa) were found in all molting stages. One band of chymotrypsin (21.9 kDa) was observed in all molting stages. High molecular mass active bands (66-205 kDa) could not be characterized with inhibitors. Comparison of the protease-specific activity of the hepatopancreas of some species indicated a relationship between digestive enzyme activity and feeding habits of the shrimp. Omnivorous shrimp, such as Penaeus vannamei (syn: Litopenaeus vannamei) and Penaeus monodon, showed higher protease activity than the carnivorous shrimp, Penaeus californiensis (syn: Farfantepenaeus californiensis) and P. muelleri. In fact, the enzymatic activity in the hepatopancreas of P. muelleri showed variations in relation to feeding habit and molting cycle.     

Changes in lipid and fatty acid composition of late larval and puerulus stages of the spiny lobster (Panulirus cygnus) across the continental shelf of Western Australia

The feeding of the late larval stages of the spiny lobster, Panulirus cygnus, and the energy reserves used by the non-feeding post-larvae for crossing the continental shelf of Western Australia were examined through their lipid composition. Lipid was a significant component of the biomass of all larval and post-larval samples (range 63-213 mg g(-1) of dry biomass). The fatty acid profiles of late stage larvae (8-9) suggest that they were feeding on salps and small crustaceans, such as euphausids, from oligotrophic pelagic communities where herbivorous and microbial grazing is an important basis to the food web. There was a marked decrease in lipid content of post-larvae progressively across the continental shelf, and this corresponded closely with decreasing dry mass, suggesting that post-larvae were using lipid as an energy source during cross-shelf movement at a rate of 1.6 J km(-1). This is considerably lower than for other spiny lobster species, suggesting that the post-larvae of the western rock lobster may use physical processes as well as active swimming for onshore transport. This may help to explain the large inter-annual variability in the post-larval settlement of this species, which is closely related to differences in weather patterns capable of greatly varying onshore advection processes.     

Eel protection measures within the Manapouri hydro-electric power scheme,South Island,New Zealand

Variation in developmental rate from fertilization to swim-up, and body size at swim-up, may affect the growth and survival of young-of-the-year fish. Fish egg size (diameter) is often positively correlated to adult female size, but whether increased egg size equates to higher egg nutrient content and subsequently improved embryo/larval performance, remains unclear. Artificially fertilized northern pike eggs from individual females (total length 400–800 mm) were cultured under temperature controlled laboratory conditions to test the hypothesis that female body size positively influences egg size and the amount of specific nutrients (carbon, nitrogen, phosphorus, and fatty acids) allocated to eggs. We further hypothesized that greater egg nutrient content would positively influence egg survival, developmental rate, and the size of swim-up fry. These hypotheses were investigated in the context of two different northern pike spawning strategies (early season tributary vs. late season deep shoal spawning). Nutrients were allocated conservatively in northern pike eggs, showing very little variation in nutrient concentrations, but the total mass of all egg nutrients increased linearly with egg dry mass. Neither egg dry mass nor nutrient content (concentration or mass), were related to either egg diameter or female body size. The mass of individual egg nutrients was, however, strongly correlated with egg dry mass (r ² range 0.62 to 0.99 for individual nutrients) and positively related to the total length of swim-up fry (r ² = 0.58). The eggs of late spawning pike had significantly greater dry mass (average = 3.02 mg/egg) and developed more rapidly to swim-up (average = 17.89 days) than did those of early spawners (average = 2.28 mg/egg, 19.05 days). Our results indicate that egg quality may be best assessed by egg dry mass, which was correlated with greater nutrient mass and increased swim-up fry body length, as opposed to egg diameter or female body size which showed no correlation to egg nutrient composition and egg/larval performance. Guest editors: J. M. Farrell, C. Skov, M. Mingelbier, T. Margenau & J. E. Cooper International Pike Symposium: Merging Knowledge of Ecology, Biology, and Management for a Circumpolar Species     

An evaluation of condition indices and predictive models for noninvasive estimates of lipid mass of migrating Common Yellowthroats, Ovenbirds, and Swainson's Thrushes

ABSTRACT.   Noninvasive methods of measuring lipid mass in birds are widely used, but not frequently evaluated. I evaluated the ability of three noninvasive indicators of fat content (fat scores, body mass, body mass/wing chord) and regression models to predict lipid mass in two migratory songbirds previously unexamined in this context—Common Yellowthroat ( Geothlypis trichas ) and Ovenbird ( Seiurus aurocapillus ). I also examined the accuracy of these methods for Swainson's Thrushes ( Catharus ustulatus ) for comparison to a previous study. Fat score, body mass, and body mass/wing chord were highly correlated with chemically extracted lipid mass in each species. In all three species, birds with no visible subcutaneous fat possessed considerable quantities of fat, ranging from 9.8 to 19.7% of total dry body mass. Forward-selected regression models explained 69−87% of lipid mass variation, with prediction errors of 14.6−27.5%. An existing predictive model for the Swainson's Thrush overestimated lipid mass by an average of 92%. Fat score, body mass, and the regression models generated here are reliable predictors of lipid mass in two of the three migrating species examined. The accuracy of the methods, in addition to their low cost and simplicity, justifies their continued use in field studies of birds.     

Evaluation of phloxine B as a photoinsecticide on immature stages of the horn fly, Haematobia irritans (L.) (Diptera: Muscidae)

The use of photoactive substances for controlling adult or immature stages of insect pests is an attractive alternative to chemical insecticides. Phloxine B is an environmentally friendly xanthene derivative that is safe for mammals but toxic for dipterans. In this study we tested the effect of phloxine B as a phototoxic larvicide against immature stages of the blood-sucking horn fly, Haematobia irritans (L.). The mortality rate of phloxine B was very low in the dark during the larval stage (100 h) unless a 0.5-mM dye concentration was used. However, a high mortality rate was attained when larvae III were transferred to containers exposed to 5000 lux during the last 2 h before pupariation. This was concentration-dependent up to 0.1-mM phloxine B. After a 2-h larval exposure to light the phloxine B 50% lethal concentration was 0.043 mM. These results indicate that H . irritans larvae are very sensitive to this dye, which in turn seems a promising component for larvicide formulations to control horn flies.     

中国沿海无柄蔓足类研究进展

无柄蔓足类属节肢动物门甲壳纲,是海洋生态系统和污损生物群落中极为重要的组成部分,在中国海域分布着6科25属110种,主要种类为纹藤壶(Balanus amphitrite amphitrite)、网纹藤壶(B.reticulatus)、高峰星藤壶(Chirona amaryllis)、泥藤壶(Balanus uliginosus)、白脊藤壶(B.albicostatus)、三角藤壶(B.trigonus)、红巨藤壶(Megabalanus rosa)、钟巨藤壶(M.tintinnabulum tintinnabulum)、白条地藤壶(Euraphia withersi)、鳞笠藤壶(Tetraclita squamosa squamosa),其中纹藤壶在黄、渤海为优势种,网纹藤壶则在热带和亚热带海区占优势;泥藤壶多出现在沿海河口的咸淡水交汇处;三角藤壶、红巨藤壶和钟巨藤壶等种类分布于盐度较高的海域。环境因子可对无柄蔓足类的生长发育、繁殖附着、分布状况及形态特征等产生显著影响。幼虫发育阶段要经历6期无节幼虫和1期金星幼虫,青岛大扁藻(Platymonas helgolandica)、牟式角毛藻(Chaetoceros muelleri)和亚心形扁藻(Platymonas subcordiformis)均是幼虫培养较为理想的饵料;金星幼虫可在4—8℃下保存1周左右。藤壶胶粘物由蛋白亚基聚合而成,其初生胶和次生胶组成基本相似。无柄蔓足类不仅是开展防除测试和生态科学研究的理想材料,而且还应进一步分析其在海洋生态系统中的地位和作用,并从分子水平探讨幼虫附着机理、胶粘物作用机制、种类相互关系与系统发生史。     

Effects of osmotic stress on crustacean larval growth and protein and lipid levels are related to life-histories: the genus Armases as a model

In the larval stages of three euryhaline species of the genus Armases, we tested if changes in biomass (dry mass, W; protein; lipid) under hyposmotic stress were related to their salinity tolerance, capabilities of osmoregulation, and migration patterns. As model species, we compared Armases miersii, which breeds in supratidal rock pools, the riverine crab Armases roberti (showing a larval export strategy), and Armases ricordi, whose larvae probably develop in coastal marine waters. At each stage, larvae were exposed to different salinities (selected according to previous information on larval survival; range: 5 per thousand-32 per thousand for A. miersii, 10 per thousand-32 per thousand for A. roberti, and 15 per thousand-32 per thousand for A. ricordi). Biomass was measured in early postmoult and intermoult. The larvae of the strongly osmoregulating species A. miersii, which develop in habitats with highly variable salinity conditions, showed the smallest variations in biomass. The effect on A. roberti varied during its ontogeny: the Zoea I and the Megalopa, which carry out downstream and upstream migrations, respectively, showed lower biomass variations than the intermediate zoeal instars, which develop in coastal waters. The larvae of A. ricordi showed generally the highest variations in biomass, reflecting poor adaptation to salinity variations. In addition, a common pattern was found for these estuarine species: the maximum of biomass shifted during ontogeny from 32 per thousand to 25 per thousand, reflecting changes of the iso-osmotic point. The ontogeny of osmoregulation reflected ontogenetic migration patterns, which allow for avoiding detrimental effects of salinity variations.     

Development of the parasitoid,Cotesia rubecula (Hymenoptera: Braconidae) in Pieris rapae and Pieris brassicae (Lepidoptera: Pieridae): evidence for host regulation

Several recent models examining the developmental strategies of parasitoids attacking hosts which continue feeding and growing after parasitism (=koinobiont parasitoids) assume that host quality is a non-linear function of host size at oviposition. We tested this assumption by comparing the growth and development of males of the solitary koinobiont endoparasitoid, Cotesia rubecula, in first (L1) to third (L3) larval instars of its preferred host, Pieris rapae and in a less preferred host, Pieris brassicae. Beginning 3 days after parasitism, hosts were dissected daily, and both host and parasitoid dry mass was determined. Using data on parasitoid dry mass, we measured the mean relative growth rate of C. rubecula, and compared the trajectories of larval growth of the parasitoid during the larval and pupal stages using non-linear equations. Parasitoids generally survived better, completed development faster, and grew larger in earlier than in later instars of both host species, and adult wasps emerging from P. rapae were significantly larger than wasps emerging from all corresponding instars of P. brassicae. During their early larval stages, parasitoids grew most slowly in L1 P. rapae, whereas in all other host classes of both host species growth to pupation proceeded fairly uniformly. The growth of both host species was markedly reduced after parasitism compared with controls, with the development of P. brassicae arrested at an earlier stage, and at a smaller body mass, than P. rapae. Our results suggest that C. rubecula regulates certain biochemical processes more effectively in P. rapae than in P. brassicae, in accordance with its own nutritional and physiological requirements. Furthermore, we propose that, for parasitoids such as C. rubecula, which do not consume all host tissues prior to pupation, that parasitoid size and host quality may vary independently of host size at oviposition and at larval parasitoid egression.     

Phylogenetic relationships of freshwater sponges (Porifera, Spongillina) inferred from analyses of 18S rDNA, COI mtDNA, and ITS2 rDNA sequences

The phylogenetic relationships of nine species of freshwater sponges, representing the families Spongillidae, Lubomirskiidae, and Metaniidae, were inferred from analyses of 18S rDNA, cytochrome oxidase subunit I (COI) mtDNA, and internal transcribed spacer 2 (ITS2) rDNA sequences. These species form a strongly supported monophyletic group within the Demospongiae, with the lithistid Vetulina stalactites as the sister taxon. Within the freshwater sponge clade, the basal taxon is not resolved. Depending upon the method of analysis and sequence, the metaniid species, Corvomeyenia sp., or the spongillid species, Trochospongilla pennsylvanica , emerges as the basal species. Among the remaining freshwater sponge species, the spongillids, Spongilla lacustris and Eunapius fragilis , form a sister group to a clade comprised of the spongillid species, Clypeatula cooperensis , Ephydatia fluviatilis , and Ephydatia muelleri , and the lubomirskiid species, Baikalospongia bacillifera and Lubomisrkia baicalensis . C. cooperensis is the sister taxon of E. fluvialitis , and E. muelleri is the sister taxon of ( B. bacillifera + L. baicalensis ). The family Spongillidae and the genus Ephydatia are thus paraphyletic with respect to the lubomirskiid species; Ephydatia is also paraphyletic to C. cooperensis . We suggest that C. cooperensis be transferred to the genus Ephydatia and that the family Lubomirskiidae be subsumed into the Spongillidae.     

Characterization of the growth and lipid content of the diatom Chaetoceros muelleri

Chaetoceros muelleri (Schütt) was cultured on a thermal gradient plate, subjected to two media types with a range of specific conductances, and evaluated for growth and neutral lipid accumulation. Growth was measured directly by daily changes in cell numbers and indirectly by changes in optical density at 750 nm. C. muelleri exhibited a growth rate of at least two doublings day-1 over broad temperature (20 to 35 °C) and conductance ranges (10 to over 60 mS cm-1) and the optimum growth rate approached 4.0 doublings day-1 at 30 °C and a conductance of 25 mS cm-1. Intracellular neutral lipid storage was evaluated with fluorometry and epifluorescent microscopy using the fluorochrome Nile Red. Gravimetric analysis revealed a total lipid content in nitrogen-depleted cultures of C. muelleri of over 400 mg L-1, five to seven times that observed in nitrogen-replete cultures. Based on its high growth rate, tolerance to a broad range of temperatures and specific conductances, and large quantity of intracellular lipid, C. muelleri may have potential for exploitation as a renewable precursor to liquid fuels or as a lipid source. This revised version was published online in August 2006 with corrections to the Cover Date.     

Lipid content of terrestrial arthropods in relation to body size,phylogeny, ontogeny and sex

Energy storage in arthropods has important implications for survival and reproduction. The lipid content of 276 species of adult arthropods with wet mass in the range 0.2–6.13 g is determined to assess how lipid mass scales with body mass. The relative contribution of lipids to total body mass is investigated with respect to phylogeny, ontogeny and sex. The lipid content of adult insects, arachnids, and arthropods in general shows an isometric scaling relationship with respect to body mass (M) (M_{arthropod lipid} = ?1.09 ×M_dry^1.01 and M_{arthropod lipid} = ?1.00 ×M_lean^0.98). However, lipid allocation varies between arthropod taxa, as well as with sex and developmental stage within arthropod taxa. Female insects and arachnids generally have higher lipid contents than males, and larval holometabolous insects and juvenile arachnids have higher lipid contents than adults.