Taxonomy
Synonyms
Meringium dimidiatum (Mett.) Copel. • Hymenophyllum piliferum C.Chr.Red List Status -
Least Concern (LC) , assessed in 28/11/2018
Hymenophyllum dimidiatum is a saxicolous and an epiphytic fern endemic of New Caledonia, restricted in the south of Grande Terre. This species is common and abundant and is found in dense humid forest from 200 to 1,480 m asl. With an extent of occurrence (EOO) equal to 3,562 km² and an area of occupancy (AOO) of 104 km², H. dimidiatum does not seem threatened and therefore is assessed as Least Concern (LC).
Geographical area
Hymenophyllum dimidiatum is endemic to New Caledonia where it is restricted in the south of Grande Terre, from Plaine des Lacs to Mont do with an observation at Nodéla in the centre of Grande Terre.
Population
Population size is unknown. Field surveys emphasize a locally abundant and common species in the south of Grande Terre.
Habitat
Hymenophyllum dimidiatum is a saxicolous and an epiphytic fern which occurs in dense humid forest from 200 to 1,480 m asl.
Threats
This species does not seem to be threatened.
Conservation
Hymenophyllum dimidiatum is not protected by legislation however it does occur in several protected areas: Haute Yaté, la Dumbéa, Massif du Kouakoué, Montagne des sources, Mont Do, Mont Humboldt, Mont Mou, Nodela, Rivière bleue, Vallée de la Thy, Côte Oubliée, Forêt de Saille, Haute Dumbéa.
Bibliography
Ebihara A., Dubuisson J.-Y., Iwatsuki K., Hennequin S., Ito M. 2006. A taxonomic revision of Hymenophyllaceae. Blumea(51(2)) , p.221-280.
Munzinger J., Morat Ph., Jaffré T., Gâteblé G., Pillon Y., Rouhan G., Bruy, D., Veillon J.-M., & M. Chalopin. 2019. FLORICAL: Checklist of the vascular indigenous flora of New Caledonia..
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
Ebihara A.,Iwatsuki K., Ito M., Hennequin S., Dubuisson J.Y. 2007. A global molecular phylogeny of the fern genus Trichomanes (Hymenophyllaceae) with special reference to stem anatomy. Botanical Journal of the Linnean Society,(155(1)) , p.1-27.
Del Rio, A. & al. 2017. Origins of the fern genus Hymenophyllum (Hymenophyllaceae) in New Caledonia: Multiple independent colonizations from surrounding territories and limited in situ diversification. Taxon(66(5)) , p.1041-1064.
Experts
Assessor(s): Amice, R., Butin, J., Garnier, D., Veillon, J., Fleurot, D., Laudereau, C., Suprin, B., Mandaoué, L.
Reviewer(s): Tanguy, V.
Contributor(s): Rouhan, G., Perrie, L.
Facilitator(s): Warimavute, G., Meyer, S.