Patrick Ranirison

Dr. Patrick Ranirison

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Research Focus & Metrics

Academic Career Length

1Year (2026-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2026 in Candollea
Verified
Journal Article
Open access
PDF file
JHJohan Hermans
Johan Hermans
PRPatrick Ranirison
Patrick Ranirison
AHAlessandra Havinga
Alessandra Havinga
IHIharivolana
Iharivolana
LNLouis et Jardin botaniques Nusbaumer
Louis et Jardin botaniques Nusbaumer
Les recherches taxonomiques et moléculaires sur les genres de la sous-tribu Goodyerinae de Madagascar et des îles adjacentes de l'océan Indien occidental sont discutées. Les caractéristiques de Goodyera R.Br. et Platylepis A.Rich. sont comparées, et leur histoire est présentée. Les espèces actuellement acceptées par les auteurs pour la région sont détaillées. Une nouvelle espèce d'orchidée, Platylepis avaratraensis Hermans & Nusb., est décrite dans la région de Sava, au nord de Madagascar. Elle est illustrée et comparée à d'autres espèces du genre. Elle est la plus proche de P. humicola (Schltr.) Schltr., mais se distingue par ses feuilles plus larges, ses bractées florales plus courtes, la couleur de ses fleurs, des sépales plus étroits et un labelle avec des callosités distinctes. La distribution et l'écologie de la nouvelle espèce sont discutées et son statut de conservation préliminaire est évalué comme «En danger» suivant les Catégories et Critères de la Liste rouge de l'UICN.

2 September 2026 in Remote Sensing
Verified
Journal Article
Open access
PDF file
AHAlessandra Havinga
Alessandra Havinga
Gregory GiulianiGregory Giuliani
Gregory Giuliani
SNSophie Nobel
Sophie Nobel
PRPatrick Ranirison
Patrick Ranirison
LNLouis et Jardin botaniques Nusbaumer
Louis et Jardin botaniques Nusbaumer
PMPascal Martin
Pascal Martin
Accurate land-cover mapping in tropical regions remains challenging because of high environmental heterogeneity, complex vegetation structure, and persistent cloud cover. Recent geospatial foundation models provide pre-computed Geo-embeddings that offer a new representation of Earth Observation data (EO), yet their potential for detailed tropical land-cover mapping and their performance relative to, and in combination with, conventional Sentinel-1 and Sentinel-2 satellite image time series remains largely unexplored. This study evaluated AlphaEarth Foundation Geo-embeddings for detailed vegetation mapping in northern Madagascar and investigated whether combining them with satellite image time series processed using the Satellite Image Time Series (SITS) R package could improve classification performance. Geo-embeddings were classified using a Random Forest model (GEO), while four supervised classifiers were trained on Sentinel-1 and Sentinel-2 time series. GEO achieved the highest standalone performance (OA = 0.74), outperforming all classifiers trained on the satellite image time series. Probability-level ensemble models were then used to assess whether both data representations could be beneficially combined. The best-performing ensemble, combining GEO (75%) with Temporal Convolutional Neural Network (TempCNN; 25%), increased overall accuracy from 0.74 to 0.82. These results suggest that Geo-embeddings provide an effective standalone representation for detailed tropical land-cover mapping and indicate that combining them with conventional satellite image time series may exploit complementary information. As geospatial foundation models continue to evolve, understanding how they can be integrated with established Earth observation workflows may support future operational land-cover mapping.

28 August 2026 in bioRxiv
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Preprint
Open access
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JSJordi Salmona
Jordi Salmona
BRBesoa Ranjavao
Besoa Ranjavao
EREmmanuel Rasolondraibe
Emmanuel Rasolondraibe
ARAndo Nantenaina Rakotonanahary
Ando Nantenaina Rakotonanahary
TRTantely Ralantoharijaona
Tantely Ralantoharijaona
LCLounès Chikhi
Lounès Chikhi
Among Madagascar primates, the sportive lemurs (family Lepilemuridae) have seen their species diversity increase from eight in 2005 to 26 in 2009 mostly by applying the phylogenetic species concept to DNA barcode data. Despite the genus being speciose, only one case of sympatry is known from northern Madagascar, where two sportive lemur species described based on low mtDNA divergence, Lepilemur ankaranensis and Lepilemur milanoii , were found to co-occur at the center of their joint distribution range. Here, to clarify the taxonomy of these two species and examine their sympatry, we apply an integrative taxonomic framework to genomic and morphological data from 84 individuals of L. ankaranensis and L. milanoii , encompassing their entire distribution range and the forest of Analafiana, beyond their southernmost limit. Using clustering, multivariate, and isolation by distance analyses, we find no evidence of a sympatric zone and show that despite clear genetic differentiation between regions, the genomic and morphological diversity of the L. ankaranensis - L. milanoii - Analafiana group is clinal and explained by geographic distance. These results clarify that L. milanoii is a junior synonym of L. ankaranensis and that the Analafiana forest population belongs to L. ankaranensis , extending its distribution. It further implies that the “sympatric” zone—the Andrafiamena forest—hosts conspecific individuals with slightly differentiated mtDNA backgrounds, rather than slightly differentiated sympatric species. Lastly, we re-evaluate the IUCN conservation metrics of L. ankaranensis , which continue to qualify as Endangered (EN) under the B1ab(i-v) criteria.