Achene traits involved in the water dispersal of the invasive Fallopia × bohemica complex: Variability and dispersal strategies

We describe a new species of dung beetle, Epactoides giganteussp. nov., from a single female specimen allegedly collected in the 19th century on Réunion island and recently found at the Muséum national d’Histoire naturelle, Paris. This species differs from other species of Epactoides by larger size and a set of other distinctive morphological characters. Epactoides giganteussp. nov. is the first native dung beetle (Scarabaeinae) of Réunion, and its discovery expands the known area of distribution of the genus Epactoides, which was hitherto believed to be endemic to Madagascar. Like other taxa from Madagascar and peripheral islands (e.g., Comoro, Seychelles, Mascarenes), E. giganteussp. nov. may have reached Réunion by over-water dispersal. Given the rapid loss of biodiversity on Réunion island and the fact that no additional specimens were re-collected over the last two centuries, it is very likely that E. giganteussp. nov. has gone extinct. However, we have unconfirmed evidence that the holotype of E. giganteussp. nov. might be a mislabeled specimen from Madagascar, which would refute the presence of native dung beetles on Réunion. We discuss both hypotheses about the specimen origin and assess the systematic position of E. giganteussp. nov. by examining most of the described species of Madagascan Epactoides. Additionally, we provide a brief overview of the dung beetle fauna of Mascarene Archipelago.

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Chloroplast DNA Variation of Carapa guianensis in the Amazon basin

Silvae Genetica ◽

10.1515/sg-2005-0039 ◽

2005 ◽

Vol 54 (1-6) ◽

pp. 270-274 ◽

Cited By ~ 12

Author(s):

D. Cloutier ◽

J. S. R. Póvoa ◽

L. C. Procopio ◽

N. V. M. Leão ◽

L. H. De O. Wadt ◽

...

Keyword(s):

Chloroplast Dna ◽

Amazon Basin ◽

Geographic Population ◽

Dna Variation ◽

Carapa Guianensis ◽

Neotropical Tree ◽

Water Dispersal ◽

Site Variation ◽

Chloroplast Dna Variation ◽

Limited Gene Flow

Abstract Carapa guianensis is a widespread Neotropical tree species that produces a seed adapted for water dispersal. We conducted a pilot study of chloroplast DNA (cpDNA) variation in order to investigate the consequences of hydrochory on genetic diversity and geographic population structure in the lower Amazon basin. A survey of cpDNA haplotype variation reveals a strong regional structure, which suggests limited gene flow by seeds. Within site variation was detected only in one floodplain forest (varzea), suggesting that seed dispersal by water in these forests has the potential to mix maternal lineages. Several phylogeographic hypotheses are discussed with respect to these data.

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Calonectria pseudonaviculata Conidia Dispersal and Implications for Boxwood Blight Management

Plant Health Progress ◽

10.1094/php-04-20-0024-rs ◽

2020 ◽

Vol 21 (4) ◽

pp. 232-237

Author(s):

James A. LaMondia ◽

Katja Maurer

Keyword(s):

Best Management Practices ◽

Management Practices ◽

Water Droplets ◽

Abaxial Surface ◽

Best Management ◽

Air Sampler ◽

Water Films ◽

Splash Dispersal ◽

Water Dispersal ◽

Half Strength

We investigated Calonectria pseudonaviculata conidial dispersal from sporulating lesions on boxwood leaves and sporulating cultures on half-strength PDA (1/2 PDA). Botrytis cinerea-infected blossoms were used as a control. Dispersal of C. pseudonaviculata or Botrytis conidia was confirmed by capture using an Allergenco air sampler at 15 liters/min and by microscopic observation of conidia and C. pseudonaviculata growth on 15-cm-diameter 1/2 PDA Petri dishes. C. pseudonaviculata conidia were not dispersed by either dry or moist air currents directed at conidia and conidiophores from 2 mm away at air speeds of 19.8 m/s for 10 min or by a fine mist with water droplets (mean diameter 20 µm) with air speeds of 1.7 m/s. C. pseudonaviculata spores were dispersed by splash of water droplets at air speeds of 9.0 to 19.8 m/s. C. pseudonaviculata conidia released from phialides by water could not be wind dispersed after the water had evaporated. Secondary water dispersal was reduced because conidia strongly adhered to a surface after drying. Boxwood leaves dropped from heights of 15, 33, or 66 cm landed with more than 60% of leaves facing abaxial surface up. The cupped shape of most boxwood leaves may result in the abaxial surface with sporulation facing up. That orientation may also aid in retention of water films to wet and release conidia for splash dispersal. This is consistent with observations of increased disease severity in lower boxwood canopies and reinforces suggestions for best management practices including mulching and pruning lower branches to reduce the incidence and severity of disease.

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Potential for dispersal of Gyrodactylus salaris (Platyhelminthes, Monogenea) by sea-running stages of the Atlantic salmon (Salmo salar): field and laboratory studies

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-251 ◽

1998 ◽

Vol 55 (2) ◽

pp. 507-514 ◽

Cited By ~ 20

Author(s):

Arnulf Soleng ◽

Tor A Bakke ◽

Lars P Hansen

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

River Mouth ◽

Infected Fish ◽

Surface Salinity ◽

Wild Salmon ◽

Atlantic Salmon Salmo Salar ◽

Water Dispersal ◽

Salmon Parr ◽

Salmon Smolt

Population growth of Gyrodactylus salaris increased exponentially on Atlantic salmon (Salmo salar) smolts in laboratory experiments conducted at 12.0°C. Furthermore, G. salaris was transmitted successfully from salmon smolt to parr at 0.0, 7.5, 10.0, and 20.0%° salinity and reproduced in fresh water after direct transfer from 7.5%° (16 days), 20.0%° (4 and 8 h), and 33.0%° (5, 15, and 30 min). No G. salaris were observed on salmon parr exposed to 33.0%° for 60 min. The prevalence of G. salaris on wild salmon smolts caught approximately 25 km from the river mouth in the Drammensfjord (surface salinity 2.0-3.5%°) was 71.2% compared with 88.0% on those from the neighbouring River Lierelva. Adult wild salmon caught as prespawners, spawners, and postspawners (kelts) in the River Drammenselva were infected with G. salaris. The prevalence and abundance increased from autumn to spring, in contrast with earlier studies on salmon parr, demonstrating the possible importance of adult salmon as reservoirs for G. salaris during winter. The results support the hypothesis of brackish water dispersal of G. salaris by infected salmonids migrating in estuaries and fjords. The use of salt as a disinfectant against G. salaris in hatcheries, and the stocking of possibly infected fish into brackish and seawater, should also be reexamined.

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Over-water dispersal of lizards due to hurricanes

Nature ◽

10.1038/26886 ◽

1998 ◽

Vol 395 (6702) ◽

pp. 556-556 ◽

Cited By ~ 151

Author(s):

Ellen J. Censky ◽

Karim Hodge ◽

Judy Dudley

Keyword(s):

Water Dispersal

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Revisiting the biogeography of Sideroxylon (Sapotaceae) and an evaluation of the taxonomic status of Argania and Spiniluma

Australian Systematic Botany ◽

10.1071/sb14010 ◽

2014 ◽

Vol 27 (2) ◽

pp. 104 ◽

Cited By ~ 8

Author(s):

Gail Stride ◽

Stephan Nylinder ◽

Ulf Swenson

Keyword(s):

Central America ◽

North Atlantic ◽

Divergence Time ◽

Taxonomic Status ◽

Migration Route ◽

Gulf Of Aden ◽

Long Distance ◽

The North ◽

Water Dispersal ◽

Mascarene Islands

Biogeography of Sideroxylon (Sapotoideae) and whether the satellite genera Argania and Spiniluma merit recognition are revisited. The hypothesis of an African origin with a subsequent migration to Central America via Europe and the North Atlantic landbridge is challenged. We analysed 58 accessions of trnH-psbA and ITS sequences in a fossil-calibrated, relaxed lognormal clock model with BEAST for phylogenetic and biogeographic inference. Argania spinosa (L.) Skeels from Morocco must be united with Sideroxylon, whereas S. discolor Radcl.-Sm. and S. oxyacanthum Baill. belong to subfamily Chrysophylloideae and may be recognised as Spiniluma. The divergence time estimate suggests that Sideroxylon originated and first diversified in Central America 56.3–52.2 million years ago, contemporaneous with the landbridge, but an archipelago of islands and the Tethys Seaway halted eastward expansion to Africa until c.20 million years ago, i.e. 25 million years after establishment in Africa. Range expansion of Sideroxylon was therefore not powered by the landbridge, and a long-distance dispersal from Central America to Africa is proposed. The establishment of the Gomphotherium landbridge between Africa and Eurasia at 19 million years ago provided a land-migration route to Europe and Asia, which is reconcilable with the extension of Xantolis into Asia. Sideroxylon has colonised Socotra by over-water dispersal in the Gulf of Aden, Macaronesia, Madagascar and the Mascarene Islands.

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Salinity tolerance of Gyrodactylus salaris (Platyhelminthes, Monogenea): laboratory studies

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-089 ◽

1997 ◽

Vol 54 (8) ◽

pp. 1837-1864 ◽

Cited By ~ 21

Author(s):

A Soleng ◽

T A Bakke

Keyword(s):

Population Growth ◽

Survival Time ◽

Fresh Water ◽

Salinity Tolerance ◽

Sea Water ◽

Infected Fish ◽

Laboratory Studies ◽

Water Dispersal ◽

Significant Difference ◽

Parasite Survival

The salinity tolerance of the freshwater monogenean Gyrodactylus salaris, infecting Atlantic salmon (Salmo salar) parr, was studied experimentally. Following direct transfer of infected fish from fresh water to 5.0omicron salinity, parasite population growth increased at the same rate as in fresh water and was positively correlated with temperature (1.4, 6.0, and 12.0°C). In 7.5omicron salinity the populations declined and became extinct after a maximum of 56 days, without any significant difference between 6.0 and 12.0°C. However, some infrapopulations demonstrated short periods of growth. At higher salinities (10.0, 15.0, 20.0, and 33.0omicron) the survival time decreased, and there was a negative correlation between survival time and temperature (1.4, 6.0, and 12.0°C). When transferred directly to sea water (33.0omicron) the parasites became opaque and ceased moving after a few minutes. There was no difference in parasite survival time between direct and gradual transfer from fresh water to 7.5 and 10.0omicron, except for one infrapopulation which demonstrated population growth from day 22 after some fluctuations following gradual transfer to 7.5omicron. The present findings support the hypothesis of brackish water dispersal of G. salaris with infected fish migrating between rivers in fjord systems.

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