Reproductive dynamics of three amphibian species in Mediterranean wetlands: the role of local precipitation and hydrological regimes

1. Although the influence of water availability and precipitation regimes on amphibians has been studied at large scales, whether and how interannual rainfall and hydrological variations affect amphibians dynamics at a local scale have rarely been addressed. In this respect, accounting for variations in species detectability in space and time has also been overlooked. 2. We assessed the effects of rainfall and hydrological variations on the breeding dynamics of three amphibian taxa: Pelodytes punctatus, Hyla meridionalis and Pelophylax spp. in 20 ponds of the Camargue region (southern France) over a 7‐year study period. 3. We used multiple season occupancy models to test the effect of winter–spring rainfall and interannual variations in hydroperiod, mean water depth and drought events on tadpole presence in spring (March–June), a proxy for breeding dynamics. 4. We used an independent survey with spatial replicates (dipnet sweeps) to disentangle the relative contributions of phenology and detectability to the absence of records in a given month. For the three taxa considered, the probability of missing a species when that species was actually present in a pond was most often negligible. Hence, we could consider that multiseason models properly tracked changes in species phenology. 5. Pelodytes punctatus was first detected in March, while the two other taxa appeared later in April. Hyla meridionalis appeared as a mid‐season species with much more synchronous pond occupancy than Pelodytes punctatus. The detection peak of Pelophylax spp. was short and unexpectedly early for this taxon. 6. Seasonal winter–spring rainfall was associated with a decrease in extinction rates and even more strongly with an increase in colonisation rates at individual ponds. 7. Colonisation rate increased following an annual drought and was best modelled as a negative quadratic effect of the variance of pond hydroperiod. Extinction probability was best modelled by a negative quadratic effect of mean water level. Hence, breeding was more stochastic (i) in unpredictable and shallow ponds because of yearly drying up and (ii) in highly predictable and deep ponds, possibly due to the presence of predators such as fish and crayfish. 8. Overall, we show that ponds with intermediate rather than extreme variations in environmental conditions currently correspond to optimal breeding sites. Our study demonstrates that amphibian monitoring coupled with fine‐scale analysis of environmental conditions is necessary to understand species dynamics in the long run and to inform conservation efforts for these species.     

Modelling temperature-dependent bionomics of Bemisia tabaci (Q-biotype)

Abstract.  The influence of temperature (17, 21, 25, 30 and 35 °C) on life-history traits of a Q-biotype Bemisia tabaci population on tomato is studied. Temperature-dependent relationships are characterized for immature developmental rate, immature survival, fecundity, longevity and intrinsic rate of increase. Development time vary from 20 days at 30 °C to 56 days at 17 °C and the lowest thermal threshold is estimated at 10.2 °C. The optimal temperature for immature development is 32.5 °C. Total fecundity (eggs per female) ranges from 105.3 (at 21 °C) to 41 (at 35 °C). The longevity decreases with temperature increase. The intrinsic rate of increase ranges from 0.0450 (at 17 °C) to 0.123 (at 30 °C). The functional relationships between temperature and life-history parameters are used to evaluate the effect of temperature on the population dynamics. Such mathematical relationships could provide a basis for future development of population models.     

Invertebrate hydraulic preferences and predicted impacts of changes in discharge in a large river

• 1 Instream habitat models are attractive tools for assessing the impacts of flow restoration on aquatic organisms, but have been rarely used for invertebrates due to the lack of knowledge of their hydraulic preferences.
• 2 In this study, we provide quantitative models of the hydraulic preferences for 66 invertebrate taxa found in the Upper Rhône River (France), and combine these preferences with a statistical habitat model (FSTress) to predict the effects of minimum flow restoration on invertebrate abundances in two bypassed sections of the river.
• 3 Many taxa show marked preferences for particular hydraulic conditions. Average preferred hydraulic conditions were significantly related to those observed in smaller streams (R² = 0.37).
• 4 Our model predicted that habitat values of 27 taxa should be enhanced by restoration operations, but also predicted a decrease of habitat values in the main channel for 12 limnophilic taxa. However, these taxa are expected to maintain populations by finding refuges in restored cut‐off channels and overall invertebrate diversity is predicted to increase in the two bypassed sections studied here.

     

Character state‐based taxa erected to accommodate fossil and extant needle stoneflies (Leuctridae – Leuctrida tax.n.) and close relatives

In order to accommodate a newly discovered fossil specimen related to a subset of extant needle stoneflies (Leuctridae sensu Zwick, 2000), we provide a comparative analysis of the wing venation of these insects, and of their close relatives, primarily based on extant material. A number of character states potentially supporting monophyletic taxa are identified, and are used to erect taxon names under the cladotypic nomenclatural procedure. We introduce a new standard definition in which the mention of the antonym of the defining character state is applied. The proposed taxa, and taxa inclusiveness, are as follows: Nemouromorpha > Capniida/Leuctrida/‘Nemouridae s.l.’, and Leuctrida > Exeleuctrida > Mioleuctrida & Eleuctrida > Collaleuctrida. This scheme allowed us to tentatively accommodate several fossil species described earlier and the new specimen, left undetermined at the genus and species levels, but assigned to Collaleuctrida. To optimize retrieval of hierarchical information, we introduce the use of ‘nec’ (Latin for ‘but not’) into the taxonomic address to indicate exclusion from a taxon. For example, Mioleuctrida nec Collaleuctrida ?yehae indicates that ?yehae can be assigned to Mioleuctrida but can also be conclusively excluded from Collaleuctrida. Based on the investigated case, it is finally argued that the cladotypic nomenclatural procedure is optimal regarding name use and numbers, and allows adequate treatment of homoplasy.     

Evolution of the Malagasy endemic genus Nanos Westwood, 1842 (Coleoptera,Scarabaeidae, Epilissini)

The traditionally defined ‘Nanos group’, composed of the genera Nanos Westwood, 1842, Cambefortantus Paulian, 1986 and Apotolamprus Olsoufieff, 1947, represents the most recent Malagasy dung beetle radiation. Species in this group have been ecologically very successful with many being numerically dominant in local dung beetle communities in Madagascar. In this study the phylogenetic relationships of species in this group are inferred using molecular data from mitochondrial (cytochrome c oxidase I) and nuclear (rudimentary, topoisomerase I and 28S) genes.The monophyly of Apotolamprus is supported both by molecular and morphological characters, but that of Nanos, supported by only one morphological character, is questioned. Congruent species groups can be defined within Nanos on the base of morphology and molecular results. In addition to the phylogenetic study, the revision of the genus Nanos Westwood, 1842, s.l., is presented. Nanos antsihanakensis (Lebis, 1953) stat.n . is re‐established. Thirteen new species – Nanos pseudofusconitens sp.n ., Nanos magnus sp.n ., Nanos marojejyensis sp.n ., Nanos bemarahaensis sp.n ., Nanos andreiae sp.n ., Nanos mirjae sp.n ., Nanos pseudorubromaculatus sp.n ., Nanos pseudominutus sp.n ., Nanos mixtus sp.n ., Nanos ranomafanaensis sp.n ., Nanos manongorivoensis sp.n ., N. pseudoviettei sp.n . and N. constricticollis sp.n . – are described and compared with their most closely related taxa. Sphaerocanthon fallaciosus Lebis, 1953, is synonymised with Nanos fusconitens (Fairmaire, 1899) syn.n . and Nanos neoelectrinus Montreuil & Viljanen, 2007, with Nanos humeralis Paulian, 1975 syn.n . Lectotypes are designated for Epilissus fusconitens var. agaboides Boucomont, 1937, Epilissus punctatus Boucomont, 1937, Epilissus sinuatipes Boucomont, 1937, Epilissus semiscribrosus Fairmaire, 1898, Epilissus fusconitens Fairmaire, 1899, and Sphaerocanthon vadoni Lebis, 1953. Aedeagus and male pro‐ and metatibiae are illustrated for each species. This published work has been registered in Zoobank, http://zoobank.org/urn:lsid:zoobank.org:pub:C1F29A37‐E380‐4D87‐871F‐039227547156 .