A new geographical record for Habenaria rhodocheila subsp. philippinensis?

-
Habenaria rhodocheila subsp. philippinensis

Nov. 9- We were driving along a stretch of a road in the province of Laguna when we decided to check out a waterfall where one of my companions, Ronald, said held a population of Begonia tayabensis, one of the few peltate-leaved Begonia species found in the Philippines, a claim later proved true. This spot also supported some terrestrial orchids, notably the common and widespread Calanthe mcgregori and Geodorum densiflorum, as well as some Hetaeria oblongifolia and Zeuxine. But while photographing plants of the Begonia on a boulder, my eyes caught sight of a white-flowered Habenaria which I initially thought to be H. robinsonii, a species restricted to very few sites on Luzon, in the provinces of Laguna, Batangas, and Quezon. This taxon bear flowers with large, stark white labella and is a showier example in a genus dominated by more cryptic, green-colored blooms. However, I later realized that what we found wasn't this species, but something else. The only other Philippine species with a broad white labellum is H. rhodocheila subsp. philippinensis which is known from Mindanao. Indeed, it appears that these two similar species are geographically separated from one another, with the intervening islands of Visayas serving as a barrier. This discovery could be the first example of this subspecies to be found on Luzon. 

How does one tell the two apart? The width of the leaves is a very good spot character. The leaves of H. robinsonii are narrow and grass-like, being only about a centimeter wide, often narrower. The foliage of H. rhodocheila subsp. philippinensis are much broader, and in one of the specimens located- the one in the photo below, the leaves were about 3.5 cm. wide; the broadest leaf of the flowering example illustrated above measured 2.7 cm. in breadth. Few other traits separate the two but in H. robinsonii the sepals are white (vs. green). Both taxa share the same ecological preferences, growing usually on rocks in fast-flowing small bodies of water such as creeks and streams, but H. robinsonii prefers lower altitudes not exceeding ca. 150 m., whereas H. rhodocheila subsp. philippinensis occurs at a wider altitudinal band from 60 to 1000 m. Our specimens were found at an elevation of about 350 m. We (Ernie Alvaran, who is also interested in species orchids, and I) found only three plants, but it is hoped that more individuals can be spotted once a more thorough search is undertaken.

Please also check https://philippineplants.org/Families/OrchidaceaeD-M.html to see photos of these two similar taxa.

A fruiting specimen of Habenaria rhodocheila subsp. philippinensis almost fully hidden amongst Begonia tayabensis.
P.S.

Do not expect the scientific community to take this report seriously, especially since the announcement was made very informally, on a blog. I would have written a more formal write-up in a reputable journal but I am still in my orchidology doldrums. Once these plants are detected by academe-produced botanists, then a more formal article may follow suit. Let's just let them take the credit.



Comments

Post a Comment

Popular posts from this blog

Plants and places: a list of places in the Philippines that were named after plants

-
Image
Many place names within the Philippines were taken from plants, historical figures, or from water features or references to it. However, the former appears to be much more widespread and perhaps reflect the early people's affinity with such plants, perhaps as sources of folk medicine, food, utilities, or simply as landmarks. Unfortunately, most of these place names no longer bear the plants so honored, and the meaning of such names have been largely lost to obscurity. Our so-called 'progress' has pulled us farther and farther away from nature: the nonstop road widening projects during the last five years have wreaked havoc on not a few roadside trees. A Facebook post shows the last and only known Acacia confusa - a Philippine endemic- along the Olongapo-Bugallon Road in the western Luzon province of Zambales that is slated for cutting. Some names are contentious, such as 'Balicbalic' and 'Vigan'. Still, many of these place names reflect a place's topogr
Read more

Distinguishing Alocasia boyceana, A. heterophylla, and A. ramosii, and some words about asking for plant identification

-
Image
  In the Philippines, three commonly encountered Alocasia species are frequently mixed with one another that identification of plants posted in social media has resulted in a muddied concept of what constitutes what, with most plants getting labeled as ' Alocasia heterophylla ' even though practically no one can elucidate why he thinks it is that species. More on that later. Still, admit I should that I, too, was confused not too long ago until I got fed up with my own ignorance and decided to undo it once and for all. I now show thee the path to thy enlightenment. The main aim of this article is to allow you to reliably identify which is which. I am going to keep this ultra-simplified, so I am not going to talk about floral morphologies. People usually don't catch them in flower anyway and very few have the inclination to save dissected inflorescence samples in an alcohol solution for later reference. The other aim, well, we'll get to that later. Alocasia heterophylla
Read more

Phalaenopsis: a photographic compendium of Philippine species

-
Image
The genus  Phalaenopsis  requires no introduction, and its species, in their myriad variations and color forms, are still much sought around the world even after more than a century of introduction. And for this post, I present to you the Philippine species which are among the most spectacular in the genus. Phalaenopsis amabilis Phalaenopsis amabilis labellum Phalaenopsis amabilis , albinistic form Phalaenopsis aphrodite subsp. aphrodite Phalaenopsis aphrodite subsp. formosana Phalaenopsis intermedia Phalaenopsis intermedia, red lip Phalaenopsis intermedia, yellow lip Phalaenopsis intermedia, pink form Phalaenopsis philippinensis Phalaenopsis sanderiana Phalaenopsis sanderiana Phalaenopsis schilleriana Phalaenopsis stuartiana Phalaenopsis stuartiana fma.  nobilis Phalaenopsis  x  veitchiana Phalaenopsis equestris Phalaenopsis  equestris  fma . alba A
Read more