Biology subjects

REBELO, M. D. F.

Publications and source records attributed to REBELO, M. D. F..

3 recordsLinked to original sources

bioRxiv2025

The globally dispersed sun-coral species is _Tubastraea coccinea_ (Cnidaria: Anthozoa)

Species of the genus Tubastraea (sun corals) have dispersed globally over recent decades, but morphological trait identification has led to taxonomic confusion, with multiple authors proposing conflicting species identifications due to high morphological plasticity and overlapping diagnostic traits. We combined global-scale molecular phylogenetics with chromosome-level genome assemblies to resolve this taxonomic issue. Using mitochondrial and nuclear markers from 287 specimens across five ocean regions, including type localities in Bora Bora (T. coccinea) and Galapagos (T. tagusensis), we reconstructed phylogenetic relationships and inferred demographic history through approximate Bayesian computation. We also generated high-quality, chromosome-level genome assemblies for three morphologically distinct morphotypes from the Brazilian coastline. Phylogenetic and species delimitation analyses revealed two well-supported clades: a small, geographically restricted T. tagusensis clade confined to the Galapagos Islands, and a large cosmopolitan clade containing all worldwide samples, including T. coccinea from its type locality. Chromosome-level genomic analyses confirmed that the three morpho-types represent a single species, sharing a triploid karyotype of 14 chromosomes with extensive synteny and gene-tree discordance consistent with incomplete lineage sorting. Dispersed-route analyses identified the Centralwestern Pacific as the ancestral source, with at least three independent, humanmediated colonization events establishing populations in the Southwestern Atlantic, Gulf of Mexico, and Western Pacific. However, preliminary analysis suggests a Galapagos (Southeastern Pacific) origin rather than Centralwestern Pacific for the T. tagusensis and T. coccinea cluster. Our results definitively establish Tubastraea coccinea as the cosmopolitan species responsible for global dissemination, while T. tagusensis is endemic to the Galapagos and not involved in the worldwide dis-persion.

genetics↗

bioRxiv2025

eDNA enables proof-of-origin of samples from reservoirs with rich and abundant biodiversity

Environmental DNA (eDNA) is increasingly used for biodiversity monitoring, but its application in verifying the geographic origin of samples remains limited. Here, we evaluated whether eDNA profiles from water samples can indicate sample provenance across three large Brazilian reservoirs. Using multi-marker metabarcoding (COI, 12S, 16S), we showed that biodiversity signatures enable spatial attribution. To ensure traceability, each report was encoded in a machine-readable format, hashed, and registered on the blockchain. This framework demonstrates a novel approach to independently verifying sample origin through molecular and cryptographic evidence.

ecology↗

bioRxiv2020

The genomes of invasive coral Tubastraea spp. (Dendrophylliidae) as tool for the development of biotechnological solutions

Corals have been attracting huge attention due to the impact of climate change and ocean acidification on reef formation and resilience. Nevertheless, some species like Tubastraea coccinea and T. tagusensis have been spreading very fast replacing the native ones which affect the local environment and decrease biodiversity of corals and other organisms associated with them. Despite some focal efforts to understand the biology of these organisms, they remain understudied at the molecular level. This knowledge gap hinders the development of cost-effective strategies for both conservation and management of invasive species. In this circumstance, it is expected that genome sequencing would provide powerful insights that could lead to better strategies for prevention, management, and control of this and other invasive species. Here, we present three genomes of Tubastraea spp. in one of the most comprehensive biological studies of corals, that includes flow cytometry, karyotyping, transcriptomics, genomics, and phylogeny. The genome of T. tagusensis is organized in 23 chromosomes pairs and has 1.1 Gb, the T. coccinea genome is organized in 22 chromosome pairs and has 806 Mb, and the Tubastraea sp. genome is organized in 21 chromosome pairs and has 795 Mb. The hybrid assembly of T. tagusensis using short and long-reads has a N50 of 227,978 bp, 7,996 contigs and high completeness estimated as 91.6% of BUSCO complete genes, of T. coccinea has a N50 of 66,396 bp, 17,214 contigs and 88.1% of completeness, and of Tubastraea sp. has a N50 of 82,672 bp, 12,922 contigs and also 88.1% of completeness. We inferred that almost half of the genome consists of repetitive elements, mostly interspersed repeats. We provide evidence for exclusive Scleractinia and Tubastraea gene content related to adhesion and immunity. The Tubastraea spp. genomes are a fundamental study which promises to provide insights not only about the genetic basis for the extreme invasiveness of this particular coral genus, but to understand the adaptation flaws of some reef corals in the face of anthropic-induced environmental disturbances. We expect the data generated in this study will foster the development of efficient technologies for the management of coral species, whether invasive or threatened.

evolutionary biology↗