ERGA-BGE reference genome of Carlina diae, an endemic spineless thistle of Crete, Greece

<ns3:p> <ns3:italic>Carlina diae</ns3:italic> ( <ns3:italic>Asteraceae</ns3:italic> ) is a rare Cretan endemic plant confined to limestone cliff crevices in four locations of eastern Crete, as well as Dia and the Dionysades islets. It is the only species of the <ns3:italic>Carlina</ns3:italic> genus lacking spiny structures, a trait that, together with its placement in the ancestral subgenus <ns3:italic>Lyrolepis</ns3:italic> , highlights its significance as a Tertiary relict and a representative of an ancient evolutionary lineage. Fewer than 1,000 mature individuals persist in fragmented subpopulations, each typically numbering fewer than 250 plants, all within Natura 2000 sites, which are protected areas covering Europe's most valuable and threatened species and habitats. The species is currently classified as Endangered on the IUCN Red List. Despite its restricted range, <ns3:italic>C. diae</ns3:italic> contributes substantially to ecosystem functioning. It can stabilize shallow soils on rocky slopes and support the integrity of fragile montane habitats. Flowering during the dry summer months, its capitula provides critical nectar and pollen resources for pollinators, including solitary bees, thereby sustaining biodiversity during periods of resource scarcity. Unlike several species of the <ns3:italic>Asteraceae</ns3:italic> family with ornamental value, <ns3:italic>C. diae</ns3:italic> is not cultivated and is poorly represented in ex-situ collections, underscoring the urgency of conservation measures. Genomic studies, including full genome annotation, are expected to play a pivotal role in safeguarding its genetic diversity, informing effective management strategies, and improving understanding of its unique evolutionary history. The entirety of the genome sequence was assembled into 10 contiguous chromosomal pseudomolecules, 2 mitochondrial genomes, and one plastid genome. This chromosome-level assembly encompasses 4.2 Gb, composed of 456 contigs and 102 scaffolds, with contig and scaffold N50 values of 23.5 Mb and 416.6 Mb, respectively. </ns3:p>