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Rafanomezantsoa, J.-J.

Publications and source records attributed to Rafanomezantsoa, J.-J..

3 recordsLinked to original sources

Genome assemblies and annotations of the poneroid ants Platythyrea mocquerysi (Ponerinae) and Stigmatomma oregonense (Amblyoponinae)

We present draft genome assemblies for two poneroid ant species with distinctive life history traits: Platythyrea mocquerysi Emery, 1899 (Ponerinae) and Stigmatomma oregonense Wheeler, 1915 (Amblyoponinae). Platythyrea mocquerysi is a Malagasy ant in which larvae produce secretions from a ventral tubercle that are consumed by adults, representing an unusual form of larva-to-adult trophallaxis. Stigmatomma oregonense, a North American "dracula ant," feeds non-lethally on larval haemolymph. Using PacBio HiFi long-read sequencing, we assembled the P. mocquerysi genome (187 Mb, 307 scaffolds, N50 = 5.26 Mb, BUSCO 99.2% complete) and the S. oregonense genome (262 Mb, 1,189 scaffolds, N50 = 0.84 Mb, BUSCO 98.3% complete). These genomes encode 10,860 and 12,354 protein-coding genes, respectively. Repeat content is higher in S. oregonense than in P. mocquerysi, 54.3% against a lower bound of 15.7%. Most of the difference is in unclassified repeats, which we show to be diverged transposable elements. Comparative analysis with two additional poneroid genomes from closely related species reveals that genome size variation across poneroid ants is largely explained by transposable element dynamics, with notable expansions in several gene families including carboxylesterases, serine proteases, and lipid metabolism genes in Amblyoponinae. These genomes provide essential resources for investigating the molecular basis of unconventional brood management strategies in ants.

genomics↗

Data of the Insect Biome Atlas: a metabarcoding survey of the terrestrial arthropods of Sweden and Madagascar

We present the data from the Insect Biome Atlas project (IBA), characterizing the terrestrial arthropod faunas of Sweden and Madagascar. Over 12 months, weekly Malaise trap samples were collected at 203 locations within 100 sites in Sweden and at 50 locations within 33 sites in Madagascar; this was complemented by soil and litter samples from each site. The field samples comprise 4,749 Malaise trap, 192 soil and 192 litter samples from Sweden and 2,566 Malaise trap and 190 litter samples from Madagascar. Samples were processed using mild lysis or homogenization, followed by DNA metabarcoding of COI (418 bp). The data comprise 698,378 non-chimeric sequence variants from Sweden and 687,866 from Madagascar, representing 33,989 (33,046 Arthropoda) and 77,599 (77,380 Arthropoda) operational taxonomic units, respectively. These are the most comprehensive data presented on these faunas so far, allowing unique analyses of the size, composition, spatial turnover and seasonal dynamics of the sampled communities. They also provide an invaluable baseline against which to gauge future changes.

ecology↗

Neoisoptera repetitively colonised Madagascar after the Middle Miocene climatic optimum

Madagascar is home to many endemic plant and animal species owing to its ancient isolation from other landmasses. This unique fauna includes several lineages of termites, a group of insects known for their key role in organic matter decomposition in many terrestrial ecosystems. How and when termites colonised Madagascar remains unknown. In this study, we used 601 mitochondrial genomes, 93 of which were generated from Madagascan samples, to infer the global historical biogeography of Neoisoptera, a lineage containing upwards of 80% of described termite species. Our results indicate that Neoisoptera colonised Madagascar between seven to ten times independently during the Miocene, between 8.4-16.6 Ma (95% HPD: 6.1-19.9 Ma). This timing matches that of the colonization of Australia by Neoisoptera. Furthermore, the taxonomic composition of the Neoisopteran fauna of Madagascar and Australia are strikingly similar, with Madagascar harbouring an additional two lineages absent from Australia. Therefore, akin to Australia, Neoisoptera colonised Madagascar during the global expansion of grasslands, possibly helped by the ecological opportunities arising from the spread of this new biome.

ecology↗