Hildenbrandiales

Hildenbrandiales
Scientific classification
Phylum: Rhodophyta
Class: Florideophyceae
Order: Hildenbrandiales
Pueschel & Cole, 1982
Family: Hildenbrandiaceae
Rabenhorst, 1868
Genera[1]

Hildenbrandiales is an order of crustose forms red alga which bear conceptacles[2] and produce secondary pit-connections.[3] They reproduce by vegetative gemmae[4] as well as tetrasporangia, which are produced inside the conceptacles. The way in which the tetraspores are produced is unusual enough to justify the formation of this distinct order.[5] Some members of the order are known from freshwater rivers as well .[6]

Systematics

Hildenbradiales are difficult to discriminate on morphological grounds; tetrasporangia morphology is the only vaguely reliable character, but molecular techniques have indicated a monophyletic Apophlaea within a paraphyletic Hildenbrandia, with many Hildenbrandia species being recognized as non-monophyletic.[1]

References

  1. ^ a b Sherwood, A. R.; Sheath, R. G. (2003). "Systematics of the Hildenbrandiales (Rhodophyta): Gene Sequence and Morphometric Analyses of Global Collections". Journal of Phycology 39: 409–422. doi:10.1046/j.1529-8817.2003.01050.x.  edit
  2. ^ Pueschel, C. (1982). "Ultrastructural observations of tetrasporangia and conceptacles in Hildenbrandia (Rhodophyta: Hildenbrandiales)". European Journal of Phycology 17 (3): 333–326. doi:10.1080/00071618200650331.  edit
  3. ^ Pueschel, C. (1988). "Secondary pit connections in Hildenbrandia (Rhodophyta, Hildenbrandiales)". European Journal of Phycology 23: 25–51. doi:10.1080/00071618800650031.  edit
  4. ^ Sherwood, A. R.; Sheath, R. G. (2000). "Microscopic analysis and seasonality of gemma production in the freshwater red alga Hildenbrandia angolensis (Hildenbrandiales, Rhodophyta)". Phycological Research 48: 241. doi:10.1111/j.1440-1835.2000.tb00220.x.  edit
  5. ^ Pueschel, C. (1982). "Ultrastructural observations of tetrasporangia and conceptacles in Hildenbrandia (Rhodophyta: Hildenbrandiales)". European Journal of Phycology 17 (3): 333–326. doi:10.1080/00071618200650331.  edit
  6. ^ Khan, M. (1974). "On a fresh water Hildenbrandia Nardo. From India". Hydrobiologia 44. doi:10.1007/BF00187272.  edit