Contrasting patterns of radiation in African and Australian Restionaceae

The floras of the Mediterranean-climate areas of southern Africa and southwestern Australia are remarkably species rich. Because the two areas are at similar latitudes and in similar positions on their respective continents, they have probably had similar Cenozoic climatic histories. Here we test the prediction that the evolution of the species richness in the two areas followed a similar temporal progression by comparing the rates of lineage accumulation for African and Australian Restionaceae. Restionaceae (Poales) are typical and often dominant elements in the fynbos vegetation of the Cape Floristic Region of southern Africa and the kwongan vegetation of the Southwestern Floristic Province of Western Australia. The phylogeny of the family was estimated from combined datasets for rbcL and trnL-F sequences and a large morphological dataset; these datasets are largely congruent. The monophyly of Restionaceae is supported and a basal division into an African clade (approximately 350 species) and an Australian clade (146 species) corroborated. There is also support for a futher subdivision of these two large sister-clades, but the terminal resolution within the African clade is very weak. Fossil pollen records provided a minimum age of the common ancestor of Australian and African Restionaceae as 64-71 million years ago, and this date was used to calibrate a molecular clock. A molecular clock was rejected by a likelihood ratio test; therefore, rate changes between the lineages were smoothed using nonparametric rate smoothing. The rate-corrected ages were used to construct a plot of lineages through time. During the Palaeogene the Australian lineage diversity increased consistent with the predictions of the constant birthrate model, while the African lineage diversity showed a dramatic increase in diversification rate in the Miocene. Incomplete sampling obscures the patterns in the Neogene, but extending the trends to the modern extant diversity suggests that this acceleration in the speciation rate continued in the African clade, whereas the Australian clade retained a constant diversification rate. The substantial morphological and anatomical similarity between the African and Australian Restionaceae appear to preclude morphological innovations as possible explanations for the intercontinental differences. Most likely these differences are due to the greater geographical extent and ecological variation in temperate Australia than temperate Africa, which might have provided refugia for basal Restionaceae lineages, whereas the more mountainous terrain of southern Africa might have provided the selective regimes for a more rapid, recent speciation.     

A review of the world marine gastropod fishery: evolution of catches, management and the Chilean experience

Marine mollusks are among the most importantinvertebrate fisheries in the world. The mainclasses of mollusk fished are Cephalopoda,Bivalvia and Gastropoda. Marine gastropodsrepresent approximately 2% of the mollusksfished in the world. Several species ofgastropods, such as Haliotis spp., Strombus spp., Busycon spp. and Concholepas concholepas, have high economicvalue in international markets and playimportant social roles in small-scale artisanalfisheries. In the past 25 years wild-stockcatches of marine gastropods have increasedfrom 75,000 mt in 1979 to 103,000 mt in 1996.During the same period the countries involvedin gastropod landings rose from 23 to 47.Gastropods are fished mainly in: (1) theAmerican continent, dominated by the extractionof the muricid ``loco', C. concholepas, inChile and Peru; strombid conchs, Strombusspp., in the Caribbean, and abalone, Haliotis spp., in California and the west coastof the Baja California peninsula; (2) Asia andOceania, with the dominate abalone fishery,mainly in Australia and New Zealand, and thehorned turban snail, Turbo truncatus, inJapan and Korea; (3) in Africa and Europe, thedominate species extracted are Haliotismidae, heavily fished in South Africa, and thecommon periwinkle, Littorina littorea,and the whelk Buccinum undatum, which areextracted in Europe. This review summarizes the fishery of abalonespecies in California and the west coast of theBaja California peninsula. We highlightoverfishing situations and the utilization ofadaptive management tools, such as those inoperation in Baja California, where small-scalefisher associations (cooperatives) havereceived exclusive access rights to abaloneextraction within specific fishing zones, since1936. We also review the abalone fishery inAustralia, and the use of IndividualTransferable Quotas (ITQs) and Total AllowableCommercial Catches (TACC), which have been inuse since the mid-1980's. We describe thegastropod fisheries in Chile, mainly C. concholepas, highlighting their economic andsocial importance. We provide information onthe evolution of catches and exports anddiscuss the development of novel managementadaptive tools, such as the implementation ofthe Benthic Regime for Extraction andProcessing (BREP), the introduction ofNon-Transferable Individual Quotas (NTIQs) andterritorial users rights for benthic fisheries,such as the Management and Exploitation Areas(MEAS). Finally, we present and discuss thenecessary steps for the sustainable managementof marine gastropods and other benthic resources.     

Variation in insect damage and growth in Eucalyptus globulus

Abstract

• 1 Objectives of this study were to examine (i) between‐provenance variation in susceptibility to insects in Eucalyptus globulus and (ii) relationships between insect damage and tree growth. We planted seedlings of 18 provenances of E. globulus from south‐east Australia in a field trial and measured tree growth and insect damage.
• 2 Christmas beetles Anoplognathus spp. were the dominant herbivores during this experiment, and 99% of trees were affected by them. Defoliation of individual trees by Anoplognathus spp. ranged from 0% to 85%.
• 3 The main results of this study were that: (i) provenances of E. globulus from Tasmania and the Bass Strait islands, which had previously shown resistance to autumn gum moth Mnesampela privata and leaf blister sawfly Phylacteophaga froggatti tended to be resistant to Anoplognathus spp.; (ii) mean tree volume was reduced by herbivory; and (iii) the volume‐based performance ranking of provenances changed depending on the probability of insect outbreaks.
• 4 Fast‐growing provenances should be planted in optimal growing areas for E. globulus with low probability of insect outbreaks. However, in suboptimal growing areas, planting slightly slower growing but more resistant provenances is likely to result in greater output than planting fast‐growing provenances when the probability of insect outbreaks is high.

     

<Emphasis Type="Italic">Trichiurus nickolensis</Emphasis>, a new hairtail from Australia belonging to the <Emphasis Type="Italic">Trichiurus russelli</Emphasis> complex (Perciformes: Trichiuridae)

A new hairtail, Trichiurus nickolensis, is described on the basis of ten specimens collected off northwestern Australia, off the Northern Territory, and in the Gulf of Carpentaria, Queensland. The new species strongly resembles T. brevis Wang and You in Wang et al., 1992, off Hainan Island, South China Sea, and T. russelli Dutt and Thankam, 1966, off the Waltair Coast, Andhra Pradesh, India, in having the highest point of the supraoccipital crest situated directly above the posterior margin of the eye and a relatively short caudal peduncle. Trichiurus nickolensis differs from those two species in being strongly pigmented on the anterior section of the dorsal fin membrane (vs. slightly pigmented), and having a dorsal head margin that appears concave in lateral view, rises gently from snout tip to above middle of orbit, and then extends more steeply to dorsal fin origin (vs. rising gently from tip of snout to dorsal fin origin). The new species also has a greater number of dorsal fin rays (III, 138–143 vs. III, 127–132 and III, 127–131 in T. brevis and T. russelli, respectively) and total vertebrae (160–166 vs. 147–155 and 149–153), and shorter preanal length (mean 30% TL vs. 33% TL and 35% TL), head length (11% TL vs. 12% TL and 13% TL) and upper jaw length (4% TL vs. 5% TL and 5% TL).     

Effects of decomposition on carcass attendance in a guild of carrion-breeding flies

Many forensically important calliphorids, sarcophagids and muscids (Diptera) oviposit or larviposit on corpses only during the early stages of decomposition, yet individuals may attend bodies throughout decay. A field study was conducted to investigate how patterns of carcass use and attendance by some fly species are affected by decomposition. Five fly traps were placed in the forest and baited with whole, fresh piglet carcasses. Piglets decomposed in traps throughout the experiment, and all were skeletonized within 6 days. Flies were trapped at both early and late decomposition stages, and the species and population structures of trap catches were compared. More flies attended carcasses early rather than late in decay. For all species, flies attending early were mainly gravid females, but few gravid females attended late in decay. No females ovi- or larviposited late in decay, whereas females of all fly species deposited offspring early in decay. The number of males trapped of each species correlated positively with the number of females with eggs at early development stages. Observations were made of fly predation by European wasps Vespula germanica Fabricius (Hymenoptera, Vespidae) and jumper ants Myrmecia pilosula Smith (Hymenoptera, Formicidae) throughout the experiment. There was a higher risk for smaller fly species of being killed following predator attack. Ants and wasps attacked smaller fly species, whereas only wasps attacked larger fly species.     

Collection of wind-borne haematophagous insects in the Torres Strait,Australia

Circumstantial evidence has implicated wind-borne mosquitoes (Diptera: Culicidae) in the introduction of Japanese encephalitis (JE) virus into Australia from the New Guinea mainland. A study was initiated on Saibai Island in the northern Torres Strait, during January and February 2000, to identify the potential source of insects collected in aerial (kytoon) and surface-level traps. Wind speed and direction were recorded to determine wind profiles during insect sampling. Northerly winds capable of carrying insects from New Guinea to Saibai Island were only present on three out of 18 nights sampled. Only three male mosquitoes, comprising two Verrallina funerea (Theobald) and one Ochlerotatus vigilax (Skuse), were collected in aerial samples, and were most likely of local origin. Culicoides midges were also collected in aerial nets and included gravid/parous C. bundyensis Lee and Reye, and one parous C. histrio Johannsen. Highest densities of arthropods (up to 1562/million m3) were on 30 January 2000 when NW winds, sustained for six hours, probably introduced midges from the New Guinea mainland. Adult mosquitoes (including three female Ve. funerea and a single female Ficalbia) and Culicoides (including two gravid C. bundyensis and one parous C. cordiger Macfie) were also collected in 2 m high mast nets during northerly surface winds. Although the results do not provide evidence that wind-blown mosquitoes introduced JE from New Guinea into Australia, they do not preclude that strong N winds associated with low pressure systems SW of the Torres Strait could have done so. However, results suggest that Culicoides were more likely than mosquitoes to reach high altitude and travel long distances during the light N winds experienced during the study.     

Molecular identification of some forensically important blowflies of southern Africa and Australia

One major aspect of research in forensic entomology is the investigation of molecular techniques for the accurate identification of insects. Studies to date have addressed the corpse fauna of many geographical regions, but generally neglected the southern African calliphorid species. In this study, forensically significant calliphorids from South Africa, Swaziland, Botswana and Zimbabwe and Australia were sequenced over an 1167 base pair region of the COI gene. Phylogenetic analysis was performed to examine the ability of the region to resolve species identities and taxonomic relationships between species. Analyses by neighbour-joining, maximum parsimony and maximum likelihood methods all showed the potential of this region to provide the necessary species-level identifications for application to post-mortem interval (PMI) estimation; however, higher level taxonomic relationships did vary according to method of analysis. Intraspecific variation was also considered in relation to determining suitable maximum levels of variation to be expected during analysis. Individuals of some species in the study represented populations from both South Africa and the east coast of Australia, yet maximum intraspecific variation over this gene region was calculated at 0.8%, with minimum interspecific variation at 3%, indicating distinct ranges of variation to be expected at intra- and interspecific levels. This region therefore appears to provide southern African forensic entomologists with a new technique for providing accurate identification for application to estimation of PMI.     

Effects of temperature and larval diet on development rates and survival of the dengue vector Aedes aegypti in north Queensland, Australia

Immature development times, survival rates and adult size (wing-lengths) of the mosquito Aedes aegypti (L.) (Diptera: Culicidae) were studied in the laboratory at temperatures of 10-40 degrees C. The duration of development from egg eclosion (hatching of the first instar) to adult was inversely related to temperature, ranging from 7.2 +/- 0.2 days at 35 degrees C to 39.7 +/- 2.3 days at 15 degrees C. The minimum temperature threshold for development (t) was determined as 8.3 +/- 3.6 degrees C and the thermal constant (K) was 181.2 +/- 36.1 day-degrees above the threshold. Maximum survival rates of 88-93% were obtained between 20 and 30 degrees C. Wing-length was inversely related to temperature. The sex ratio (female:male) was 1:1 at all temperatures tested (15, 20, 25 and 35 degrees C) except 30 degrees C (4:3). Under field conditions at Townsville and Charters Towers, north Queensland, the duration of immature development varied according to the container position (i.e. shaded or exposed) and the availability of food resources, as well as inversely with temperature. These data indicate that containers with an abundance of organic matter (e.g. those used for striking plant cuttings) or those amongst foliage or under trees (e.g. discarded plastic tubs and tyres) tended to produce the largest adult Ae. aegypti, which had faster development and better immature survival. As such progeny have been linked to a greater risk of dengue transmission, it would seem important to focus on control of such containers.     

The occurrence of Calanidae species in waters off Argentina

As food of planktivorous fish and likely good predictors of natural perturbations, members of the family Calanidae are recognised to be key species in ecosystems worldwide. The distribution and seasonal relative abundance of the Calanidae species occurring in the Argentine Sea were reviewed from published and unpublished data collected over the last three decades. Species are also figured in order to elucidate any possible taxonomic uncertainty. Calanoides cf. carinatus, Calanus australis and Calanus simillimus are the most abundant calanids in the region. The former two species typically inhabit inner and middle shelf waters decreasing offshore, while Calanus simillimus is distributed in the middle and outer shelf, its abundance increasing towards the shelf-break. The southern limit of the distribution of Calanoides cf. carinatus appears to be 46° S. Calanus australis is the most common large copepod in coastal and inner shelf waters off southern Patagonia. Neocalanus tonsus and Calanoides patagoniensis are a much rarer species. The latter is recorded in the southwestern Atlantic, for the first time, immediately east of Magallanes Strait and the Beagle Channel. The taxonomic status and worldwide biogeographic distribution of the region's calanids are briefly described and the patterns identified off Argentina are discussed in relation to the major hydrographic characteristics.