Friday Fellow: Hooker’s Lips

by Piter Kehoma Boll

We are always fascinated by plants that have some peculiar shape that resemble something else. And certainly one of them is the species I’m introducing today, Psychotria elata, also known as hooker’s lips or hot lips.

Found in the rainforests of Central America, in areas of middle to high elevation, the hooker’s lips is an understory shrub and produces an inflorescence that is surrounded by a pair of bracts that resemble bright red lips. Don’t look too much or you may be tempted to kiss them.

“Kiss me”, beg the hooker’s lips. Photo by Wikimedia user IROZ.*

Certainly some creatures do kiss it, especially hummingbirds, which are its pollinators, but also many species of butterflies and bees. However, when they come to kiss the red lips, they have already spread to much, in order to allow the flowers to be exposed, and do not resemble a mouth anymore.

Once the mouth is open, the magic of the kiss is gone. Photo by Dick Culbert.**

After pollination, the flowers develop into blue berries that are easily spotted by birds, which disperse the seeds. As the hooker’s lips produces fruits through the whole year, it is an important food source for fruit-eating birds.

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References:

EOL –  Encyclopedia of Life. Psychotria elata. Available at <http://eol.org/pages/1106123/overview&gt;. Access on March 5, 2017.

Silva, C., & Segura, J. (2015). Reproductive Biology and Herkogamy of Psychotria elata (Rubiaceae), a Distylous Species of the Tropical Rain Forests of Costa Rica American Journal of Plant Sciences, 06 (03), 433-444 DOI: 10.4236/ajps.2015.63049

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Friday Fellow: Mexican Giant Horsetail

by Piter Kehoma Boll

If you are walking through the forest of Central America, you may end up finding something that at first you could think is a group of bamboos, plants growing as a cylindrical segmented stem that can reach up to 7 m in height, as seen in the picture below:

A group of bamboos? Not exactly. Photo by Alex LomasAlex Lomas.*

Those are not actually bamboos, though, but specimens of the largest species of horsetail that exists today, the Mexican giant horsetail, Equisetum myriochaetum. It can be found growing naturally from Peru to Mexico in areas of fertile soil, especially along water bodies such as streams and swamps.

As other horsetails, the Mexican giant horsetail has an erect and hollow stem with very narrow leaves growing in a whirl around the “joints” of the stem. The leaves are very simple, similar to those of more primitive plants such as the spikemosses and ground pines, but are thought to be a simplification of more complex leaves, as they are more closely related to the complex-leaved ferns.

More than only the largest horsetail in the world, the Mexican giant horsetail is an important medicinal plant in Mexican folk medicine, being used to treat kidney diseases and type 2 diabetes mellitus. And as in many other occasions, laboratory studies confirmed that water extracts from the aerial parts of E. myriochaetum do indeed reduce the blood glucose levels of type 2 diabetic patients without reducing their insulin levels. One more point to traditional medicine.

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References:

EOL – Encyclopedia of Life. Equisetum myriochaetum. Available at <http://eol.org/pages/6069616/overview&gt;. Access on March 4, 2017.

Revilla, M., Andrade-Cetto, A., Islas, S., & Wiedenfeld, H. (2002). Hypoglycemic effect of Equisetum myriochaetum aerial parts on type 2 diabetic patients Journal of Ethnopharmacology, 81 (1), 117-120 DOI: 10.1016/S0378-8741(02)00053-3

Royal Botanic Garden Edinburgh. Equisetum myriochaetum. Available at <http://www.rbge.org.uk/the-gardens/plant-of-the-month/plant-profiles/equisetum-myriochaetum&gt;. Access on March 4, 2017.

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Friday Fellow: Samambaiaçu

by Piter Kehoma Boll

It’s more than time to bring a fern as a Friday Fellow, and I decided to start with one of my favorites, the Neotropical tree fern Dicksonia sellowiana, known in Brazil as Samambaiaçu or Xaxim.

A samambaiaçu in a forest in southern Brazil. Photo by Wikimedia user DeadWood II.*

The samambaiaçu occurs from southern Mexico to Uruguay and is usually found in moist forests, being a remarkable species of moist forests in southern Brazil, especially in Araucaria moist forests. It may reach several meters in height and the fronds (leaves) reach up to 2,4 m in length.

During most of the 20th century, the fibrous stems of the samambaiaçu (usually called “xaxim”) were extensively used for manufacturing flower pots or plates that served as a substrate for cultivating orchids and other epiphytic plants. As a result of this exploitation, as well as the destruction of its native habitat, the samambaiaçu is currently included in the Brazilian Red List of endangered species.

The trade of xaxim is currently forbidden by law in Brazil, so if  you ever find someone selling it somewhere, please, communicate the authorities!

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References:

Schmitt, J., Schneider, P., & Windisch, P. (2009). Crescimento do cáudice e fenologia de Dicksonia sellowiana Hook. (Dicksoniaceae) no sul do Brasil Acta Botanica Brasilica, 23 (1), 283-291 DOI: 10.1590/S0102-33062009000100030

Brazil. Law Nº 9.605/98. Available at: <http://www.planalto.gov.br/ccivil_03/leis/L9605.htm >.

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Friday Fellow: Helicopter Damselfly

by Piter Kehoma Boll

Damselflies are usually delicate versions of dragonflies, but some species challenge their place among the odonates. The most extreme example comes from the moist forests of Central and South America and is known as Megaloprepus caerulatus or the “helicopter damselfly”.

With a wingspan up to 19 cm, the helicopter damselfly is the largest of odonates and a voracious predator in both the aquatic naiad and the aerial adult forms.

An adult female. Photo by Steven G. Johnson*

Female helicopter damselflies lay their eggs in water-filled tree hollows. Males are territorialists and defend the larger holes as territory, mating with females interested in laying eggs there.

The aquatic juvenile stage, known as naiad or nymph, is a top predator in this reduced ecosystem, feeding on mosquito larvae, tadoples and even other odonates. As adults, they feed mainly on web-building spiders that they capture in areas that receive direct sunlight, such as forest glades.

As the population size of the helicopter damselfly depends on the number and size of available tree hollows and considering that they avoid crossing large gaps between forest patches, any environmental disturbance may have profound impacts on this species. Recent molecular studies also suggest that what is known as Megaloprepus caerulatus is actually a complex of species, as there is no genetic flow between the populations. This makes it (or them) a much more vulnerable species.

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References:

Feindt, W., Fincke, O., & Hadrys, H. (2013). Still a one species genus? Strong genetic diversification in the world’s largest living odonate, the Neotropical damselfly Megaloprepus caerulatus Conservation Genetics, 15 (2), 469-481 DOI: 10.1007/s10592-013-0554-z

Wikipedia. Megaloprepus caerulatus. Available at < https://en.wikipedia.org/wiki/Megaloprepus_caerulatus >. Access on September 7, 2016.

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Friday Fellow: Tapeti

by Piter Kehoma Boll

What would be better to celebrate Easter than bringing a bunny to the Friday Fellow?

Meet the tapeti (Sylvilagus brasiliensis), also known as forest rabbit or forest cotton tail. It is a very cute rabbit found from southeastern Mexico to northern Argentina and southern Brazil, being the most widespread rabbit species in South America.

Cute as any rabbit, the tapeti is also well camouflaged. Photo by Dick Culbert.

Measuring around 30 cm in length and having a brown dorsum with black speckles, the tapeti can hide itself easily in its environment, which includes forests, savannas and grasslands from the sea level up to 4,800 m of altitude. The camouflaged appearance is probably the reason why it is so rarely spotted, even though it is a very common species. The fact that it is mainly active during dawn and dusk may also lower the chances to see it properly. The IUCN classify it as “Least Concern”.

If you live in South or Central America, try to pay attention while walking in the wilderness. Maybe you have the opportunity to spot one.

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References:

Wikipedia. Tapeti. Available at: < https://en.wikipedia.org/wiki/Tapeti >. Access on March 24, 2016.

EOL – Encyclopedia of Life. Sylvilagus brasiliensis. Available at: < http://eol.org/pages/118008/ >. Access on March 24, 2016.