Friday Fellow: Giant Clam

by Piter Kehoma Boll

One more giant is coming to our team, again from the sea, but this time from the bilvavian molluscs. Its name is Tridachna gigas, commonly known as the giant clam.

Found in shallow coral reefs of the Indian and Pacific Oceans, especially around Indonesia, the giant clam can grow up to about 1.2 m, weigh more than 200 kg and live more than 100 years, being the largest living bivalve mollusk.


The giant clam is seen in coral reefs as a giant lump of molluscan material. Watch out, Dory! Photo by flickr user incidencematrix.*

One interesting aspect of the giant clam and its close relatives is that they live in a symbiotic association with some dinoflagellates (the so-called zoxanthellae, also found in corals), having even a special structure, the zooxanthellal tubular system, to house them. During the day, the giant clam exposes its mantle to the light in order to allow the algae to photosynthesize. Part of the nutrients produced by the algae are given to the clam. This allows the giant clam to survive in otherwise nutrient-poor environments, where its standard bivalvian feeding stile, by filtering partiles from the water, would not be enought to allow it to grow properly.


A half-closed shell. Photo by The Central Intelligence Agency.

The giant clam is used as food in many Asian countries, especially Japan and countries from Southeast Asia and Pacific Islands. Additionally, the giant shell is considered a valuable decorative item and can be sold for large amounts of money. Due to such exploitations, the giant clam populations are starting to decline and the species is considered vulnerable by the IUCN.


An empty shell exposed in Aquarium Finisterrae, Galicia, Spain. Photo by Wikimedia user Drow male.**

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Klumpp, D. W., Bayne, B. L., & Hawkins, A. J. S. (1992). Nutrition of the giant clam Tridacna gigas (L.) I. Contribution of filter feeding and photosynthates to respiration and growth. Journal of Experimental Marine Biology and Ecology, 155(1), 105–122. doi:10.1016/0022-0981(92)90030-e

Norton, J. H., Shepherd, M. A., Long, H. M., & Fitt, W. K. (1992). The Zooxanthellal Tubular System in the Giant Clam. The Biological Bulletin, 183(3), 503–506. doi:10.2307/1542028

Wells, S. (1996). Tridacna gigas. The IUCN Red List of Threatened Species doi:10.2305/IUCN.UK.1996.RLTS.T22137A9362283.en. Access on September 1, 2018.

Wikipedia. Giant clam. Available at < >. Access on September 1, 2018.

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Friday Fellow: Ehux

by Piter Kehoma Boll

We’ll continue among the unicellular marvels of the sea this week. This time our fellow is another member of a poorly known but hugely important group of protists, the coccolithophores.

The coccolithophores are a group of unicellular algae of the marine phytoplankton that is characterized by a series of calcium carbonate plates, called coccoliths, that cover their body, making them look like cells covered by scales.

Today we’ll know the most widespread and abundant species of this group, Emiliania huxleyi, usually simply called Ehux, which I will use here as its common name.


Scanning elctron micrograph cell of Emiliania huxleyi covered by coccoliths. Credits to Alison R. Taylor.*

Ehux is found in the oceans all around the world, being absent only close to the poles. According to the fossil record, this species appeared about 270 thousand years ago, but became the dominant coccolithophore only anout 70 thousand years ago. Due to its abundance, Ehux is an important species controling global climate. As a photosynthetic organism, it helps to increase atmospheric oxygen and decrease carbon dioxide. Additionally, the fact that its cell is covered by calcium carbonate plates increases even more its importance in removing CO2 from the atmosphere. By capturing CO2 as calcium carbonate, Ehux send it directly to the ocean floor when it dies and the shell sinks.

The life cycle of Ehux is not yet completely understood, but includes at least two different cell forms. The C form is spherical, nonmotile and covered by coccoliths (hence the name C) and can reproduce asexually by fission. Another form, called S (scaly) lacks coccoliths but is covered by a group of organic scales. This form is motile, swimming using two flagella, and also reproduces asexually by fission. How one form turns into the other is unclear, but there are some evidences that the C form is diploid and the S form is haploid, so C cells could turn into S cells by meiosis and two S cells could act as gametes and fuse to produce a new C cell. A third form, called N (naked) cell is similar to a C cell but is unable to produce the coccoliths. It is assumed that they appear by a mutation of C cells that makes them lose the ability to produce coccoliths, as N cells never change back to the C form.


A bloom of Ehux south of Great Britain as seen from a sattelite photo. Credits to NASA.

During some special conditions, such as high irradiance, ideal temperatures and nitrogen-rich waters, Ehux populations can cause blooms which extend over large portions of the ocean. This species is known as a producer of Dimethyl Sulphide (DMS), a flammable liquid that boils at 37°C and has a characteristic smell usually called “sea smell” or “cabbage smell”. The release of DMS in the atmosphere interferes in cloud formation, so that this is one more way by which Ehux influences global climate.

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Paasche E (2002) Paasche, E. (2001). A review of the coccolithophorid Emiliania huxleyi (Prymnesiophyceae), with particular reference to growth, coccolith formation, and calcification-photosynthesis interactions. Phycologia 40(6), 503–529. doi:10.2216/i0031-8884-40-6-503.1

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Friday Fellow: Giant Gromia

by Piter Kehoma Boll

Some time ago I introduced a cool unicellular alga, the Sailor’s Eyeball, which can reach about 5 cm in diameter, being one of the largest unicellular organisms known to exist.

Today  we’ll know one more creature of this type, only it is not an alga, but a testate amoeba more closely related to foraminifers. Named Gromia sphaerica, I will here call it the giant gromia.

gromia fig2

Specimens of the giant gromia from the Bahamas. Image extracted from Matz et al. (2008).

The giant gromia was first found in the Arabian Sea at depths of more than 1100 m and was formally described in 2000. It lives lying on the substrate and is usually covered by a thin layer of sediment, appearing as small spheres scattered across the sea floor. The body is spherical or grape-shaped but hollow, with the interior filled with fecal material (called stercomata) or other fluids. This spherical cell is covered by a shell, or test, of organic material which shows several small perforations by which thin expansions of the cytoplasm, forming a kind of pseudopod, can be extended. The size of the test can reach up to 3 cm in diameter, being much larger than that of its best known relative, Gromia oviformis.


Several specimens of Gromia sphaerica on the sea floor of the Bahamas with the tracks left by their movement. Extracted from Matz et al. (2008).

In 2008, another population of species was found in the waters around the Bahamas. Specimens there are not as spherical as in the population in the Arabican Sea and  were seen associated with tracks that indicate that these organisms slowly move across the sediment. The tracks clearly resemble some fossil tracks from the Pre-Cambrian period, which are usually considered an indication of the early evolution of multicellular animals. However, this discovery of unicellular organisms being able to produce tracks similar to those associated with animals raises doubt about the time of origin of multicellular animals.

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Gooday AJ, Bowser SS, Bett BJ, Smith CR (2000) A large testate protist, Gromia sphaerica sp. nov. (Order Filosea), from the bathyal Arabian Sea. Deep-Sea Research II 47: 55–73.

Matz MV, Frank TM, Marshall NJ, Widder EA, Johnsen S (2008) Giant deep-sea protists produces bilaterian-like traces. Current Biology 18(23): 1849–1854.


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The history of Systematics: Systema Naturae from 1758 to 1767-1770

by Piter Kehoma Boll

In a series of previous posts, I detailed the classification of living beings by Linnaeus in his work Systema Naturae as presented in its 10th edition, published in 1758. Here, I will present it in a summarized way and show changes that happened from the 10th edition to the 13th edition published in two parts, one 9 years later in 1767, dealing with animals, and one 12 years later, in 1770, dealing with plants.


Linnaeus classified animals in 6 classes: Mammalia, Aves, Amphibia, Pisces, Insecta and Vermes.

1. Mammalia included mammals and in 1758 they were classified in 8 orders: Primates, Bruta, Ferae, Bestiae, Glires, Pecora, Belluae, Cete (see details here).


Linnaeus’ classification of Mammals in 1758 and 1767

In 1767 the order Bestiae no longer exists. Armadillos (Dasypus) were transfered to Bruta, pigs (Sus) to Belluae and the remaining genera to Ferae. Additionally, rhinoceroses (Rhinoceros) were transfered from Glires to Belluae and one bat species was transferred from the genus Vespertilio in Primates to a new genus, Noctilio, in Glires.

2. Aves included birds and in 1758 they were classified in 6 orders: Accipitrae, Picae, Anseres, Grallae, Gallinae, Passeres (see details here).


Linnaeus’ classification of birds in 1758 and 1767

In 1767, five new genera are seen in Picae: Buphaga, the oxpeckers, Trogon, the trogons, and Oriolus, the orioles (previously in the genus Coracias), Bucco, the puffbirds and Todus, the todies. One new genus appears in Anseres, Plotus, the darters. The order Grallae receives the new genera Palamedea, the seriemas and screamers, Parra, the jacanas, and Cancroma, the boat-billed heron. The order Gallinae is increased with the new genera Didus, the dodo (which was previously a member of the genus Struthio in the order Grallae), and Numida, the guineafowl (previously in the genus Phasianus). And, finally, the order Passeres received the new genera Pipra for the manakins (previously in Parus), Ampelis, the waxwings and cotings (previously in the genus Lanius in the order Accipitrae), Tanagra, the tanagers (previously in Fringilla) and Muscicapa, the flycatchers (previously in the genera Corvus and Motacilla).

It is also interesting to notice a change in the name of the order Accipitrae to Accipitres, and the genus Jynx is here written Yunx.

3. Amphibia included reptiles, amphibians and some fish and had 3 orders: Reptiles, Serpentes and Nantes (see details here).


Linnaeus’ classification of Amphibians in 1758 and 1767

The orders Reptiles and Serpentes remained the same. The order Nantes, which in 1758 included mainly cartilaginous fishes, in 1767 included a lot of genera that were previously classified in the class Pisces, especially in the order Branchiostegi (see below).

4. Pisces included most fish and had 5 orders: Apodes, Jugulares, Thoracici, Abdominales and Branchiostegi (see details here).


Linnaeus’ classification of fishes in 1758 and 1767

The genus Ophidion was transfered from the order Jugulares to Apodes and appears spelled Ophidium. The order Thoracici received the additional genus Cepola (red bandfishes) and the order Abdominales was increased with the genera Amia (the bowfin), Teuthis and Elops (the ladyfish), as well as the genus Mormyrus, previosly in the order Branchiostegi, which ceased to exist.

5. Insecta included arthropods and had 7 orders: Coleoptera, Hemiptera, Lepidoptera, Neuroptera, Hymenoptera, Diptera, Aptera (see details here).


Linnaeu’s classification of Insects in 1758 and 1767

In the order Coleoptera, received the new genera Lucanus (stag beetles, previously in Scarabaeus), Byrrhus (pill beetles), Gyrnus (whirligig beetles), Bruchus (pea weevils), Ptinus (spider beetles), HispaLampyris (glowworms). The genera Blatta and Gryllus were transfered to Hemiptera and mantises were removed from Gryllus and received their own genus, Mantis. Addtionally, the lantern flies were removed from the genus Cicada and transferred to Fulgora. In the order Neuroptera, antlions were removed from the genus Hemerobius and transferred to a new genus Myrmeleon. In the order Hymenoptera, the cuckoo wasps were transferred from the genus Sphex to a new genus Chrysis.

6. Vermes included several worms, molluscs, echinoderms, cnidarians and hagfishes. There were 5 orders: Intestina, Mollusca, Testacea, Lithophyta and Zoophyta (see details here).


Linnaeus’ classification of worms in 1758 and 1767

From 1758 to 1767, the genus Furia, of a fictional species, was transferred from Intestina to Zoophyta, and the genus Teredo (shipworms) was transferred from Intestina to Testacea. A new genus, Sipunculus, was added to Intestina to include the peanut worms. In the order Mollusca, we find now the new genera Ascidia (sea squirts), Aplysia (sea hares), Terebella (some polychaetes, previously in Nereis) and Clio (some sea slugs). The genus Priapus, containing sea anemones, is now called Actinia. The order Testacea received the new genera Mactra (trough shells, previously in Cardium) and Sabella (fanworm, previously in Serpula). The order Lithophyta received the new genus Cellepora (for bryozoans). In the order Zoophyta we find the new genera Flustra (for bryozoans previously in Eschara), Vorticella (for ciliates previously in Hydra) and Chaos (for amoebas, previously in Volvox). An additional genus is seen in Zoophyta: Spongia (sponges), transferred from Algae, back in the plant kingdom


Plants had a much more complicated system than animals. There were the plants with regular flowers classified in classes and orders according to the number of male and female sexual organs, respectively (as you can read in detail in parts 1, 2, 3 and 4 of plants in Systema Naturae). Little has changed that except for some genera, as you can see in the table below.


Linnaeus classification of plants with regular hermaphrodite flowers in 1758 and 1770. See the image in higher resolution here.

The same is true for species in the classes Didynamia and Tetradynamia, which have flowers with stamens of different sizes. Little has changed in their classification.


Linnaeus’ classification of plants with flowers having stamens of two different sizes in 1758 and 1770.

Regarding the three classes characterized by flowers with clustered stamens, we can see two new orders in the class Monadelphia.


Linnaeus’ classification of plants having flowers with clustered stamens in 1758 and 1770.

In the class Syngenesia we can notice that the order Polygamia Superflua ceases to exist, with most of its species being transferred to Polygamia Aequalis, and a new order, Polygamia Segregata, is now present. In the class Gynandria a new order, Dodecandria, is created. See those two classes in more detail here.


Linnaeus’ classification of plants with stamens fused to each other or to the carpels in 1758 and 1770.

In the three classes of plants with male and female organs occurring in separate flowers, I think the most interesting novelty is that the genus Chara, which in 1758 was classified as a genus of algae, is now among the flowering plants in the class Monoecia, order Monandria.


Linnaeus’ classification of plants having male and female organs in different flowers in 1758 and 1770.

Finally, among the Cryptogams, the “plants without flowers”, little has changed except for the transfer of Chara to the flowering plants and Spongia to the animal kingdom.


Linnaeus classification of Cryptogams in 1758 and 1770

While Linnaeus continued to develop his own system, other classifications were being proposed. We’ll start to take a look at them in the next chapters.

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Linnaeus, C. (1758) Systema Naturae per regna tria Naturae…

Linnaeus, C; (1967) Systema Naturae per regna tria Naturae….

Linnaeus, C. (1770) Systema Naturae per regna tria Naturae…

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The history of Systematics: Plants in Systema Naturae, 1758 (Part 9)

by Piter Kehoma Boll 

The last part of the series is finally here! See also parts 1, 2, 3, 4, 5, 6, 7 and 8. The only class that remains to be introduced is Cryptogamia, the plants without flowers.

24. Cryptogamia (“hidden marriages”)

“Marriage is celebrated privately”, i.e., sexual organs are not clearly visible.

24.1 Filices (ferns)Equisetum (horsetails), Onoclea (sensitive fern), Ophioglossum (adder’s-tongue ferns), Osmunda (royal ferns), Acrostichum (leather ferns), Polypodium (polypodies), Hemionitis (hemionitises), Asplenium (spleenworts), Blechnum (hard ferns), Lonchitis (lonchitises), Pteris (brakes), Adiantum (walking ferns), Trichomanes (britstle ferns and lace ferns), Marsilea (water clovers), Pilularia (pillworts), Isoetes (quillworts).


Linnaeus’ order Filices included (from left to right, top to bottom) the common horsetail (Equisetum arvense), the sensitive fern (Onoclea sensibilis), the common adder’s tongue (Ophioglossum vulgatum), common royal fern (Osmunda regalis), golden leather-fern (Acrostichum aureum), Chinese brake (Pteris vittata), western hard fern (Blechnum occidentale), black spleenwort (Asplenium adiantum-nigrum), common polypody (Polypodium vulgare), Venus-hair fern (Adiantum capillus-veneris), lace fern (Trichomanes chinensis, now Sphenomeris chinensis), European water clover (Marsilea quadrifolia), common pillwort (Pilularia globulifera), and lake quillwort (Isoetes lacustris). Credits to Rob Hille (horsetail), Kurt Stueber (royal fern), Krzysztof Ziarnek (hard fern), Forest & Kim Starr (spleenwort, lace fern), H. Zell (polypody), Tato Grasso (Venus-hair fern), Daria Inozemtseva (quillwort), Wikimedia users JMK (brake), Keisotyo (water clover) and Kembangraps (pillwort), flickr user peganum (sensitive fern).

24.2 Musci (mosses): Lycopodium (club mosses), Porella (scaleworts), Sphagnum (sphagnums), Phascum (phascum mosses), Fontinalis (fountain mosses), Buxbaumia (bug mosses), Splachnum (dung mosses), Polytrichum (haircap mosses), Mnium (calcareous mosses), Bryum (common mosses), Hypnum (flat mosses).


Among the species in the order Musci there were (from left to right, top to bottom) the common club moss (Lycopodium clavatum), pinnate scalewort (Porella pinnata), prairie sphagnum (Sphagnum palustre), common fountain moss (Fontinalis antipyretica), common bug moss (Buxbaumia aphylla), Alpine haircap (Polytrichum alpinum), horn calcareous moss (Mnium hornum), silver moss (Bryum argenteum), cypress moss (Hypnum cupressiforme). Credits to Christian Fischer (club moss), Rafael Medina (scalewort), Bern Haynold (sphagnum), Hermann Schachner (haircap, silver moss), Bernard Dupont (calcareous moss), and Wikimedia users AnRo0002 (fountain moss) and Aconcagua (cypress moss).

24.3 Algae (algae): Jungermannia (leafy liverworts), Targionia (targionias), Marchantia (thallose liverwort), Blasia (blasia), Riccia (crystalworts), Anthoceros (hornworts), Lichen (lichens), Chara (stoneworts), Tremella (several jelly-like organisms), Fucus (brown and red algae), Ulva (sea lettuces and lavers), Conferva (several filamentous algae), Byssus (several crusty and wooly organisms), Spongia (sponges).


The diverse order Algae included (from left to right, top to bottom) the forest leafy liverwort (Jungermannia nemorea, now Scapania nemorea), common targionia (Targionia hypophylla), green tongue liverwort (Marchantia polymorpha), blasia (Blasia pusilla), floating crystalwort (Riccia fluitans), smooth horwort (Anthoceros laevis, now Phaeoceros laevis), map lichen (Lichen geographicus, now Rhizocarpon geographicum), common stonewort (Chara vulgaris), witch’s jelly (Tremella nostoc, now Nostoc commune), serrated wrack (Fucus serratus), common sea lettuce (Ulva lactuca), rock weed (Conferva rupestris, now Cladophora rupestris), golden wool (Byssus aurea, now Trentepohlia aurea), bath sponge (Spongia officinalis). Credits to Bernd Haynold (leafy liverwort, blasia), Luis Fernández García (targionia), Denis Barthel (green tongue), Christian Fischer (crystalwort), Fritz Geller-Grimm (lichen), Lairich Rig (witch’s jelly), Kristian Peters (sea lettuce), Bioimages (rock wed), JK Johnson (golden wool), Guido Picchetti (sponge) and Wikimedia users Oliver s. (hornwort), Mnolf (stonewort) and Citron (wrack).

24.4 Fungi (fungi): Agaricus (gilled mushrooms), Boletus (pore-bearing mushrooms), Hydnum (toothed mushrooms), Phallus (phallic mushrooms), Clathrus (finger-shaped fungi), Elvela (saddle-like mushrooms), Peziza (cup-shaped mushrooms), Clavaria (club-shaped mushrooms), Lycoperdon (ball-shaped mushrooms), Mucor (molds).


The order Fungi contained (from left to right, top to bottom) the field mushroom (Agaricus campestris), common red shelf-mushroom (Boletus sanguineus, now Pycnoporus sanguineus), sweet tooth (Hydnum repandum), common stinkhorn (Phallus impudicus), carnival candy slime-mold (Clathrus denudatus, now Arcyria denudata), vinegar cup (Peziza acetabulum, now Helvella acetabulum), sweet club-mushroom (Clavaria pistillaris, now Clavariadelphus pistillaris), grassland puffball (Lycoperdon cervinum, now Lycoperdon lividum), common pin-mold (Mucor mucedo). Credits to Nathan Wilson (field mushroom), Instituto Últimos Refúgios (shelf mushroom), H. Krisp (sweet tooth, vinegar cup), Jörg Hempel (stinkhorn), Bea Leiderman (slime mold), Francisco J. Díez Martín (club mushroom), Michel Beeckman (puffball) and James Lindsey (pin mold).

Here we can see that Linnaeus’ mess reached its limit. There are even animals classified as plants, as you can see sponges appearing as algae. Actually, the order Algae included species belonging to almost every currently recognized kingdom, from bacteria to animals, fungi, plants and heterokonts. The other orders are considerably more uniform.

We finished Linnaeus’ System! Yay!

I will make an additional post with a summary and then we can move on to changes that happened in following systems. See you there!

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Linnaeus, C. (1758) Systema Naturae per regna tria Naturae…

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Friday Fellow: Rowell’s Velvet Worm

by Piter Kehoma Boll

Velvet worms form an intriguing group of animals that are the sister group of arthropods and also the only animal phylum with only terrestrial species, although aquatic species are known from fossil records.

Today I decided to bring one velvet worm species to be our fellow. Scientifically known as Euperipatoides rowelli, I decided to give it the common name Rowell’s velvet worm.


A specimen of the Rowell’s velvet worm in the lab. Photo by Alan Couch.*

The Rowell’s velvet worm is found in south-east Australia inhabiting humid, temperate forests. They are small animals, with about 5 cm in lenght, and live in decaying wood, dwelling in crevices and feeding on small invertebrates, such as termites and crickets.

Logs are usually inhabited by groups of several individuals that live in a sort of social relationship and are composed of females, males and juveniles, with females being larger and occurring in larger numbers than males. A sort of hierarchical organization also seems to occur, with one female being dominant and followed in dominance by other females, with males and juveniles occupying the bottom of the pyramid. Prey capture often happens in group, and after a prey is subdued, the dominant female will eat first and only after being satiated she will allow other females to eat. Males and juveniles eat the remains left by the females.


Welcome to our log! Photo by Andras Keszei.**

New logs are colonized by wandering males. Those release feromones that attract more males and later females. Thus, newly colonized logs have a male-biased aggregation, but the number of females later surpasses that of males. It has been suggested that the initial aggregation of males helps them to attract females due to the increased concentration of feromones.

During reproduction, the male places spermatophores on the skin of the female, With the aid of the female blood cells, the body wall below the spermatophore is breeched and the sperm is released in the female’s body cavity, where it swims to the female reproductive tract.

Due to its abundance in south-east Australia, the Rowell’s velvet worm is an easily obtained species and is slowly becoming one more interesting model organism.

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Barclay S, Ash JE, Rowell DM (2000) Environmental factors influencing the presence and abundance of a log-dwelling invertebrate, Euperipatoides rowelli (Onychophora: Peripatopsidae)Journal of Zoology 250: 425–436.

Barclay S, Rowell DM, Ash Je (2000) Pheromonally mediated colonization patterns in the velvet worm Euperipatoides rowelli (Onychophora)Journal of Zoology 250: 437–446.

Reinhardt J, Rowell DM (2006) Social behavior in an Australian velvet worm, Euperipatoides rowelli (Onychophora: Peripatopsidae)Journal of Zoology 250: 1–7.

Sunnucks P, Curach NC, Young A, French J, Cameron R, Briscoe DA, Tait NN (2000) Reproductive biology of the onychophoran Euperipatoides rowelliJournal of Zoology 250: 447–460.

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Friday Fellow: Sage of the Diviners

by Piter Kehoma Boll

You probably know the common sage, Salvia officinalis, used as an aromatic herb in culinary, but today I’ll talk about one of its crazy cousins, Salvia divinorum, known as the sage of the diviners or seer’s sage.

Endemic to the Sierra Mazateca in the state of Oaxaca, Mexico, where it grows in cloud forests, the sage of the diviners is a herb that reaches about 1 m in height with large yellowish green leaves. The flowers, which are rarely produced, are typical of the family Lamiaceae, to which it belongs, and have purple sepals and white petals.


Inflorescence of the sage of the diviners. Photo by Eric Hunt.*

In its native habitat, the sage of the diviners is used by the Mazatec people to faciliate shamanic visions due to its hallucinogenic properties. The hallucinogen is called salvorin A and is a diterpenoid, although its physiological function resembles more that of opioids. With acive doses as low as 200 µg, salvorin A is the most potent hallucinogen known to naturally occur.


A bowl with a concentrated extract of dry Salvia divinorum. Photo by Wikimedia user Coaster420.

The traditional form of consumption of the leaves of the sage of the diviners is by chewing fresh leaves or by crushing laves and mixing the resulting extract with water to drink it. Smoking the dry leaves is a modern alternative, as currently the drug is becoming more and more popular around the world.

Due to the still modest consumption compared to other hallucinogens, the sage of the diviners is not well covered by legislation worlwide. Some countries consider its use legal, others made it illegal, but many do not have anything concerning its use.

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Valdés, L. J. (1994) Salvia divinorum and the unique diterpene hallucinogen, Salvinorin (Divinorin) AJournal of Psychoactive Drugs 26(3): 277–283.

Wikipedia. Salvia divinorum. Available at < >. Access on July 18, 2018.

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