Blechnum hieronymi
Content
Distribution
Asia-Tropical: Maluku (Maluku present); New Guinea present, Central Papua present, Ceram present, E Highlands present, Madang present, Milne Bay present, Morobe present, New Britain present, New Ireland present, Northern Papua present, Papua New Guinea present, S Highlands present, W Highlands present, W Sepik present
Malesia: Moluccas (Ceram, once reported), New Guinea (Northern Papua, Central Papua), Papua New Guinea (W Sepik, Madang, W Highlands, E Highlands, Morobe, S Highlands, Milne Bay, New Britain, New Ireland).
Notes
1. After study of a large number of specimens of B. hieronymi from a range of areas and habitats in Papua New Guinea we have concluded that it is not possible to separate B. hieronymi from B. decorum. The holotypes of B. hieronymi and B. decorum are similar to each other in many respects. Blechnum hieronymi is reported as epiphytic (on a dead log); and the basal stipe scales of the type are smaller than those of the type of B. decorum. The holotype of B. decorum is terrestrial with scales closer to those of B. revolutum but not as robust.
2. Some of the specimens of B. hieronymi resemble specimens of B. revolutum collected from forest or forest edge habitats in which B. revolutum does not develop such strongly revolute sterile pinnae. The two species, however, can be separated by the scales of the rhizome and basal stipe, which are very much more robust in B. revolutum.
3. Blechnum hieronymi, while always montane, tends to occur at lower altitudes and in less exposed habitats than B. revolutum.
4. The holotype of B. decorum var. dilatatum is distinct from and not closely related to B. decorum and now that we have had the benefit of access to a range of collections we have given this taxon species status as B. dilatatum; it forms a large plant with pale green fronds, thick leathery pinnae, and stramineous stipe and rhachis.
5. The frond morphology of the holotypes of B. acutiusculum and B. brassii are also similar to B. hieronymi. Both B. acutiusculum and B. brassii are reported as epiphytes, the type of the former having an erect caudex and the type of the latter a slender scandent rhizome. All these taxa are readily distinguished from B. vulcanicum s.l. in which the pinnae are adnate and the fronds variously bear characteristic straight uniseriate multicellular hairs.
2. Some of the specimens of B. hieronymi resemble specimens of B. revolutum collected from forest or forest edge habitats in which B. revolutum does not develop such strongly revolute sterile pinnae. The two species, however, can be separated by the scales of the rhizome and basal stipe, which are very much more robust in B. revolutum.
3. Blechnum hieronymi, while always montane, tends to occur at lower altitudes and in less exposed habitats than B. revolutum.
4. The holotype of B. decorum var. dilatatum is distinct from and not closely related to B. decorum and now that we have had the benefit of access to a range of collections we have given this taxon species status as B. dilatatum; it forms a large plant with pale green fronds, thick leathery pinnae, and stramineous stipe and rhachis.
5. The frond morphology of the holotypes of B. acutiusculum and B. brassii are also similar to B. hieronymi. Both B. acutiusculum and B. brassii are reported as epiphytes, the type of the former having an erect caudex and the type of the latter a slender scandent rhizome. All these taxa are readily distinguished from B. vulcanicum s.l. in which the pinnae are adnate and the fronds variously bear characteristic straight uniseriate multicellular hairs.