Archivos de diario de octubre 2017

08 de octubre de 2017

Identifying Purple Fringed Orchids

P. grandiflora vs. P. psycodes
Purple fringed orchids are hard to mistake for any other flower, yet when faced with deciding between the lesser purple fringed orchid (Platanthera psycodes) and the greater purple fringed orchid (Platanthera grandiflora), it can be difficult to settle on an ID.

First off, if you find a purple fringed orchid, it is more likely to be P. psycodes, since it is more common than P. grandiflora. Flowers on P. psycodes are often smaller and wither on the bottom before the buds on top open, whereas on P. grandiflora the flowers on the bottom typically remain open longer. The most reliable characteristics are the spur opening (round on P. grandiflora) and the rostellum lobes (with “tails” on P. grandiflora).

Before using any of these tips, remember that my drawings aren't perfect and that no individual orchid is exactly alike. Also take care not to be thrown off by color variations, lack of fringing, etc

<img src="https://johngangenexus.files.wordpress.com/2017/10/img_29541.jpg?w=525"

Ingresado el 08 de octubre de 2017 por arethusa arethusa | 7 comentarios | Deja un comentario

20 de octubre de 2017

Spiranthes magnicamporum Vs. Spiranthes cernua

I was delighted by how well received the comparison between the purple fringed orchids was and decided to make more illustrations for identification purposes. As requested, I will be focused mainly on Spiranthes for the time being. S. magnicamporum was considered the same species as S. cernua up until 1973. It can often be distinguished from S. cernua by the flared lateral sepals, the lack of basal leaves, the yellow thickened area on the labellum and by the shape of the flowers. S. cernua will often have a white labellum and basal leaves should be present while in flower. However, morphological differences can often be misleading since S. cernua is a species complex, and will occasionally exhibit traits from S. magnicamporum . Perhaps the best way to distinguish between the two is to examine the seeds, which are often polyembryonic on S. cernua, unlike those produced by S. magnicamporum

@sambiology and @eraskin, it is done! I will continue to make other illustrations throughout the year. Hope this is helpful.

<img src="https://johngangenexus.files.wordpress.com/2017/10/img_2973.jpg?w=525"

Ingresado el 20 de octubre de 2017 por arethusa arethusa | 5 comentarios | Deja un comentario