Isolation and characterization of polymorphic microsatellite loci in the scarlet ibis (Eudocimus ruber— Threskiornithidae‐Aves)

Here we presented 10 polymorphic microsatellite loci obtained from scarlet ibis through an enriched genomic library. The analysis of 45 individuals from three Brazilian natural populations showed allelic diversity ranged from three to 17 alleles, observed heterozygosity ranged from 0.03 to 0.92, and expected heterozygosity ranged from 0.06 to 0.92. These highly variable microsatellite loci can provide means for assessing overall genetic variation in its remnant natural populations, which may help the development of effective conservation programs.     

RSCA genotyping of MHC for high-throughput evolutionary studies in the model organism three-spined stickleback Gasterosteus aculeatus

Background  

In all jawed vertebrates, highly polymorphic genes of the major histocompatibility complex (MHC) encode antigen presenting molecules that play a key role in the adaptive immune response. Their polymorphism is composed of multiple copies of recently duplicated genes, each possessing many alleles within populations, as well as high nucleotide divergence between alleles of the same species. Experimental evidence is accumulating that MHC polymorphism is a result of balancing selection by parasites and pathogens. In order to describe MHC diversity and analyse the underlying mechanisms that maintain it, a reliable genotyping technique is required that is suitable for such highly variable genes.     

Mutualism between armoured scale insects and ants: new species and observations on a unique trophobiosis (Hemiptera: Diaspididae; Hymenoptera: Formicidae: Melissotarsus Emery)

The association between African armoured scale insects (Hemiptera: Coccoidea: Diaspididae) and ants belonging to Melissotarsus Emery (Hymenoptera: Formicidae: Myrmicinae) is the only trophobiosis known in which ants do not receive honeydew or nectar in exchange for protection and other services. Food reward for the ants in this mutualism remains unknown, despite repeated suggestions that diaspidids are consumed by the associated ants, thus serving as ‘domestic cattle’. We describe new observations on interactions between Melissotarsus emeryi Santschi and the diaspidid Morganella conspicua (Brain) from South Africa. Worker ants exhibited previously undescribed tending behaviours, most notably a ‘squeezing and licking’ performed on an adult female diaspidid and ‘culling’, in which a worker removed an adult female armoured scale from the host plant. These could represent the gathering of secretory products and the cultivation of an individual for consumption, respectively. An ant exclusion study over 12 days of isolation showed that adult female diaspidids and second‐instar nymphs secreted no wax or exudates that attending ants would ordinarily collect. Workers of M. emeryi did not defend their nest against invading colonies of Crematogaster and other unidentified ants: we hypothesize that the primary mode of defence is maintenance of isolation within galleries. We describe three new ant‐associated diaspidid species: Affirmaspis cederbergensis Schneider sp.n. from South Africa, Diaspis doumtsopi Schneider sp.n. from Cameroon, and Melissoaspis incola Schneider sp.n. from Madagascar. Melissoaspis formicaria (Ben‐Dov) comb.n. is transferred from Morganella (Brain). Diagnostic characteristics for Melissoaspis Ben‐Dov are revised, and additional taxonomic information defining this genus allows ease of identification. An updated identification key to the species of ant‐associated diaspidids is provided. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:632C1122-954A-4DE6-B946-8E6AB6A4D27F .     

Coextirpation of host–affiliate relationships in rivers: the role of climate change,water withdrawal,and host‐specificity

The role of climate‐related disturbances on complex host–affiliate relationships remains understudied, largely because affiliate species vary in host use and are often differentially susceptible to disturbance relative to their hosts. Here we report the first set of host–affiliate species–discharge relationships (SDR) in freshwater and examine how anticipated shifts in water availability (flow) will impact coextirpations. We used SDR for freshwater mussels and fish across 11 regions (over 350 rivers) in the continental United States that we coupled to future water availability (2070) to model mussel and fish coextirpations. We also used river‐specific host–affiliate matrices (presence–absence) to evaluate how host‐specificity (mean number of hosts used by an affiliate) and host‐overlap (extent to which affiliates share hosts) relate to extirpation vulnerability. We found that the strength and predictability of SDR models vary geographically and that mussels were more susceptible to flow alterations than fish. These patterns of extirpations were strongest in the southeast where: (1) flow reductions are expected to be greatest; (2) more species are lost per unit flow; (3) and more mussels are expected to be lost per unit of fish. We also found that overall mussel losses associated with reduction in habitat (water availability) were greater than those associated with loss of fish hosts which we assumed to be a function of host redundancy. These findings highlight the utility of SDR as a tool for conservation efforts but they also demonstrate the potential severity of reductions in mussel and fish richness as consequence of climate change and water use. Mussels provide key ecosystem services but face multiple pronged attacks from reductions in flow, habitat, and fish hosts. These losses in biodiversity and ecosystem functions can translate into major effects on food webs and nutrient recycling.