A new relictual and highly troglomorphic species of Tomoceridae (Collembola) from a deep Croatian cave

Tritomurus veles sp. n. (Tomoceridae) is described from a Croatian cave. It is characterized by troglomorphic features (absence of eyes, reduced pigmentation, slender claw, pointed tibiotarsal tenent hairs) that only compare, among Tomoceridae, to the microendemic species T. falcifer from the Pyrénées. Tritomurus veles also shares with T. falcifer the absence of macrochaetae on head, a presumably non-adaptive character that within Tomoceridae is unique to these two species. Both species have no known epigean relatives in their respective distribution areas and can be considered as relictual

FIGURES 10–13 in Superodontella gladiator, a new species of the family Odontellidae (Collembola: Poduromorpha) from Nepal with extremely elongated mouthparts

FIGURES 10–13, Superodontella gladiator sp. nov., scanning electron micrographs: 10, labium, ventral (scale 1µm); 11, general ventral view (scale 100µm); 12, right, slightly ventral side of Abd. V and VI showing the furca, right anal spine (AS) and coarse tegumentary granules (scale 10µm); 13, Ocular plate showing peri-ocular groove and sunken postantennal organ (PAO) (scale 10 µm)

L'impact des coupes forestières sur les communautés de Collemboles édaphiques de tourbière et de forêt à Bernadouze

National audienceLa tourbière de Bernadouze en Pyrénées ariégeoises est d'une richesse faunistique exceptionnelle. Elle est en particulier la zone humide la plus riche en collemboles connue à ce jour dans le monde. Sa microfaune terrestre, au sein de laquelle les collemboles jouent un rôle prépondérant, a été échantillonnée de façon approfondie depuis 2013. Une coupe forestière importante réalisée en 2016 par l'ONF sur les pentes boisées à proximité immédiate de la tourbière, s'est traduite par une ouverture importante du milieu, et un apport considérable de matériel ligneux au sol. Tirant parti de cette perturbation importante et de notre très bonne connaissance de la diversité faunistique de la forêt, nous avons lancé en 2018-2019 une campagne d'échantillonnage destinée à évaluer l'impact de cette coupe forestière sur la biodiversité des sols de forêt et de tourbière.La biodiversité de ces sols a été comparée avant et après la coupe forestière, apportant les premières données quantifiées sur la réponse d'un groupe édaphique majeur présent à la fois dans l'écosystème forestier directement perturbé et dans l'écosystème de tourbière adjacent non directement affecté.La diversité des communautés étudiées a, en forêt comme en tourbière, diminué très significativement suite à la coupe forestière de 2016: baisse modérée de la richesse spécifique globale (forêt et tourbière), mais baisse importante de la richesse moyenne par relevé (forêt et tourbière), baisse considérable des abondances, que ce soit globalement ou par relevé (forêt et tourbière), et changements importants dans la composition taxonomique des communautés (forêt). L'état actuel du sous-bois forestier et l'ouverture considérable du milieu, dont on connait l'importance pour les communautés édaphiques, suggèrent un impact direct de la coupe forestière sur la baisse de biodiversité des sols forestiers. On ne peut cependant exclure que les événements climatiques exceptionnels qui ont marqué la période d’échantillonnage, tout spécialement l'épisode caniculaire de 2019, aient pu aussi affecter fortement ces communautés, mais l'impact attendu eut là encore été moins marqué en tourbière qu'en forêt, en raison du rôle tampon des circulations hydriques. Suite à cette étude, un impact indirect de la coupe forestière sur la baisse de diversité en tourbière, à travers les flux hydriques forêt > tourbière apparaît comme une hypothèse de travail pertinente

Comparative morpho‐functional analysis of the humerus and ulna in three Western European moles species of the genus Talpa , including the newly described T. aquitania

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Elephant pinching forces

African elephants have a wide range of abilities using their trunk. As a muscular hydrostat, and thanks to the two finger-like processes at its tip, this proboscis can both precisely grasp and exert considerable force by wrapping. Thus, using a device equipped with force sensors and an automatic reward system, the trunk tip pinch force has been quantified in five captive female African savanna elephants. Results showed that the maximum pinch force of the trunk was 86.4 N, which may suggest that this part of the trunk is mainly dedicated to precision grasping. We also highlighted for the first time a difference in force between the two fingers of the trunk, with the dorsal finger predominantly stronger than the ventral finger. Finally, we showed that the position of the trunk, particularly the torsion, influences its force and distribution between the two trunk fingers. Functioning of the device The device for measuring the grasping force was a box with two force sensors connected to an electronic system. The latter recorded the pinching force and automatically released apples as a reward. Force thresholds were defined from 0.5 to 8 kg. Depending on the ability of the elephants to pinch on the sensors, thresholds were every 500g or every kilo. An apple was released when the individual achieved to pinch hard enough to pass a threshold. To release the next apple, she had to pinch harder than the previous time and exceed a new threshold. By repeating this action, the maximum force was achieved. Description of the data and file structure The data collected during this experiment is compiled in a spreadsheet in CSV format. This file contains, for each grasp ("N_Grasping"), the date ("Date"), the experiment number ("N_exp"), the identity of the elephant ("ID"), the maximum force of each trunk finger ("Force_dorsal" and "Force_ventral"), the total maximum force ("Force_max"), the bending and twisting of the trunk ("Bending" and "Twisting")

The relationship between distal trunk morphology and object grasping in the African savannah elephant ( Loxodonta africana )

International audienceBackground During reach-to-grasp movements, the human hand is preshaped depending on the properties of the object. Preshaping may result from learning, morphology, or motor control variability and can confer a selective advantage on that individual or species. This preshaping ability is known in several mammals ( i.e., primates, carnivores and rodents). However, apart from the tongue preshaping of lizards and chameleons, little is known about preshaping of other grasping appendages. In particular, the elephant trunk, a muscular hydrostat, has impressive grasping skills and thus is commonly called a hand. Data on elephant trunk grasping strategies are scarce, and nothing is known about whether elephants preshape their trunk tip according to the properties of their food.Methods To determine the influence of food sizes and shapes on the form of the trunk tip, we investigated the morphology of the distal part of the trunk during grasping movements. The influence of food item form on trunk tip shape was quantified in six female African savannah elephants ( Loxodonta africana ). Three food item types were presented to the elephants (elongated, flat, and cubic), as well as three different sizes of cubic items. A total of 107 ± 10 grips per individual were video recorded, and the related trunk tip shapes were recorded with a 2D geometric morphometric approach.Results Half of the individuals adjusted the shape of the distal part of their trunk according to the object type. Of the three elephants that did not preshape their trunk tip, one was blind and another was subadult.Discussion and perspectives We found that elephants preshaped their trunk tip, similar to the preshaping of other species’ hands or paws during reach-to-grasp movements. This preshaping may be influenced by visual feedback and individual learning. To confirm these results, this study could be replicated with a larger sample of elephants

<i>Francisella halioticida</i>'s towards the mussel <i>Mytilus edulis</i> is strain-dependent

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Community ecology of the terrestrial small mammals of Zakouma National Park, Chad

The terrestrial small mammal community of the Zakouma National Park (Chad) was assessed by live trapping in various habitats during the dry season. Nearly 3000 trap-nights yielded 505 captures of nine rodent and two shrew species, making up a representative small mammal community for the Sudanian savanna biotic zone. Murine rodents of the genusMastomys dominated, withM. erythroleucus andM. cf.kollmannspergeri occuring at similar abundances. The former was widespread and especially abundant in habitats with high tree cover. The latter was more localized, predominantly in annually flooded habitats characterized by a clay-rich soil, often withAcacia seyal as the main vegetation. Population structure differed between the two species, suggesting distinct reproductive strategies possibly linked with habitat preferences: theM. erythroleucus population comprised mainly young, immature individuals, whereasM. cf.kollmannspergeri was represented by older individuals, a significant fraction of which had already reproduced.Taterillus congicus andTatera kempi (gerbilline rodents), together withLemniscomys zebra, were mainly found in more open habitats with sand-rich soils.Arvicanthis niloticus, Acomys cf.johannis, Mus mattheyi andXerus erythropus were the other rodents captured, whereas shrews were represented byCrocidura fulvastra andSuncus sp

Influence of strains in development of francisellosis in the blue mussel Mytilus edulis during experimental challenges

International audienceThe bacterium Francisella halioticida, known to induce francisellosis in abalone and Yesso scallop, is suspected of being involved in the blue mussel mortalities observed in France. Recently, several isolates of F. halioticida were obtained from moribund mussels and categorized into two type strains, FR21 and FR22. Two other strains, AG1 and AG3, determined to belong to the genus Francisella were isolated. To determine the virulence of these isolates, juvenile and adult blue mussels were injected with bacterial solutions at high dose and monitored for 11 days. FR22c and FR22d were found to induce 80% mortality in less than seven days. The isolates AG1 and AG3 led to over 50% mortality in adult mussels but only AG1 led to significant mortality in juveniles (41%). FR22c and FR22d, the most virulent isolates, were selected to determine their respective lethal dose at 50% (LD50) in juveniles and adults. This analysis was performed with bacterial solutions ranging from 10$^2$ to 10$^6$ CFU/mussel and monitored for 30 days. The isolate FR22c was found to be the most virulent. Observed LD50 for the isolate FR22c was 4.14 ×10$^3$ CFU/juvenile and 3.45 ×10$^3$ CFU/adult and for the isolate FR22d, 1.89 ×10$^4$ CFU/juvenile and 1.52 ×10$^4$ CFU/adult. To confirm Koch’s postulate, a selection of moribund, surviving and control animals were plated on specific media. The isolates were reisolated from moribund animals but not from surviving or controls. To confirm the proliferation, a specific real-time PCR was performed. All moribund individuals were positive by PCR. The main Ct values were lower for moribund compared to surviving animals and a dose effect was observed in DNA bacterial load. This study shows that some F. halioticida isolates are able to induce francisellosis in mussels and lead to high mortality, highlighting differences in virulence among the strains

Genomic comparison of Francisella halioticida

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