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First record of the rare crab Asthenognathus atlanticus Monod, 1933 (Crustacea: Brachyura: Varunidae) in the North Sea

Faasse Marco, Gheerardyn Hendrik, Witbaard Rob, Cuperus Joël

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 3

352--358

EN

Several species new to the area were collected while monitoring Dutch marine waters using a dredge. The varunid crab Asthenognathus atlanticus Monod, 1933 was recorded for the first time in the North Sea. Until 2008, this relatively rare crab was known from the west coast of Africa and the western Mediterranean to northern Brittany in the north. In recent years, its distribution range has expanded, as indicated by records from the Bay of the Seine and the area around Dieppe-Le Tréport. Our finding from Brown Bank (southern North Sea) indicates a further, northward expansion of its distribution range. We list the hosts with which the crab is associated. Earlier arguments for climate change as an explanation for the northward range expansion are supported.

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Cherry removal by seed-dispersing mammals : mutualism through commensal association with frugivorous birds

Hernandez A.

Polish Journal of Ecology

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2008

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Vol. 56, nr 1

127-138

EN

The consumption of Wild Cherries Prunus avium (L.) by frugivorous birds and mammals was studied in an area in northwest Spain in summer during July-August 2005, analysing in particular how the fruits were obtained by terrestrial seed-dispersing mammals. During the study cherries were practically the only ripe fleshy fruits available in the area. They were consumed by a variety of birds (16 species), with a very high mean rate of feeding visits (136 birds per hour for 10 trees, n = 4091 feeding visits). Most of these visits were by a priori seed-dispersing birds that usually swallow the fruits whole, in particular the Spotless Starling Sturnus unicolor Temminck, Blackbird Turdus merula L., Blackcap Sylvia atricapilla (L.), and Garden Warbler Sylvia borin (Boddaert). However, the large sizes of the cherries (10-17 mm) and the fact that they were often removed with the stalk attached hindered this to a great extent, especially in birds with small gape width (Sylvia warblers, with gape width <10 mm, accounted for 32% of the total feeding visits). Failure in handling the cherries and their falling to the ground was therefore common, as it was the alternative strategy of pecking the pulp without ingesting the large cherry seed. Most of the fallen cherries had been handled by birds (89% of 1241 cherries collected beneath eight trees), and 52% of the handled cherries still had the stalk attached. The cherries were frequently consumed by seed-dispersing mammals (1133 cherry seeds in 51 droppings of hedgehogs, mustelids and canids). More than 99% of the cherry seeds in mammal droppings were intact (potentially viable for germination). Considering their shoulder-heights (40 cm at the maximum) and the characteristics of the cherry trees (1.92 m mean distance from the ground to the lowest branch, n = 77 trees), seed-dispersing mammals were unlikely to have reached the branches directly from the ground without climbing. The non-climbing species (European Hedgehog Erinaceus europaeus (L.), Eurasian Badger Meles meles (L.), Red Fox Vulpes vulpes (L.) must have obtained all the fruits after they had fallen, and as a whole these species were precisely the main cherry dispersers among the mammals (94% of the total cherry seeds in mammal droppings). Western Polecats Mustela putorius (L.) and Beech Martens Martes foina (Erxleben) consumed cherries and could climb the trees to eat the fruit, and Stoats Mustela erminea (L.) did not consume cherries. Two conclusions in this study are relevant within the European context: 1) not all oversized fruits that often fall to the ground due to the action of seed-dispersing frugivorous birds are wasted, in terms of potential dispersal, and 2) non-climbing terrestrial seed-dispersing mammals can feed on the fruits that have fallen from shrubs and trees not necessarily after post-ripening natural abscission.

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Late Famennian ?Chaetosalpinx in Yavorskia (Tabulata) : the youngest record of tabulate endobionts

Zapalski M., Pinte E., Mistiaen B.

Acta Geologica Polonica

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2008

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Vol. 58, no. 3

321-324

EN

Tabulate corals are sometimes associated with other organisms occurring within their skeletons. These tabulate endobionts are common in Lower Palaeozoic (Ordovician and Silurian) and Devonian strata, but until now they have not been recognized in strata younger than early Frasnian. Here we report ?Chaetosalpinx sp. occurring within the skeletons of the tabulate coral Yavorskia sp. (Favositida, Cleistoporidae) from the latest Famennian ("Strunian") in the Etroeungt area (Northern France). It can be stated that these endobionts survived the Frasnian-Famennian boundary crisis and recovered in the Late Famennian.