No.
No.
No.
No.
No.
Wait... No.
No.
No.
No.
That's a Nelumbo!
No.
No.

Yes. Finally!

Oh... right. That's one of mine.

As you can see, there's a bit of an identity crisis for Nymphaea caerulea.

This video is a visual taxonomic key to identify the plant used in Ancient Egyptian rituals as determined in 1883 by Schweinfurth, the one named by Savigny in 1803, and described in detail by Conard in 1905.

I started writing this script thinking that I could give a broad overview of phylogeny and how caerulea violates many of the rules.

However, if I explain that as well as I want, that's going to end up being a 10 part series or something. 

For now let's just focus on what makes a caerulea a caerulea.

I'll point out the morphological features that distinguish caerulea from the masses of lily cultivars and similar looking but the not-so-related water plants.

Just remember that I am skipping *a lot* of details in favor of brevity.

Stay tuned to the end for even more caveats and go *here* if you just want a condensed pictorial list of features.

So obviously we are talking about a water plant.*Plantae*

Caerulea spend their entire lives almost completely submerged in water.

Though they can survive for several weeks in dry (but still humid) conditions seen during a drought.

That already narrows our list of potential species down quite a bit.

Plants that produce flowers are *angiosperms* and indeed caerulea does.

Very pretty flowers, in my opinion.

Seriously, you'd think I gave birth to this plant with the number of pictures I have shared of it on social media.*Insta @ElectricVeg*

Water lilies are grown primarily for their flowers, though some cultivars have extensive variegation if you are in to that sort of thing.*Foxfire*

And of course there are the medicinal aspects.

The first images you see on vendor's websites are usually of the flower to identify a cultivar quickly.

However, caerulea's flowers are not particularly spectacular, at least to the people unfamiliar with its history.

Plant breeders usually look for intense color, numerous petals, and prolific flowering among other features.

Caerulea has none of these qualities.

That's at least part of the reason why they haven't received as much horticultural attention as other, more vibrant species.

A single caerulea plant can produce up to 3 flowers per week (in my experience) during the peak growing season depending on conditions and fertility.

Though 1-2 flowers per week is more common.

The flowers are not very large, only 7-15 cm across fully expanded with 14-20 petals and 50-75 stamens.

These features make caerulea a relatively unattractive prospect for medicinal extract vendors.

I believe this is why the much more prolific flower producing species like capensis with its 20-30 dark blue petals and 150 to 275 stamens are often substituted for caerulea.

Hence the huge list of misidentified waterlilies shown at the start of this video all of which feature complete blue petals.

Because more blue equals more narcotic right? Right?

Caerulea's petals are white with a tinge of yellow/green at the base fading to pale blue sometimes light purple at the tips.

The colors will appear more saturated when dried but they never become blue at the base.

The petals maintain their blue color upon rehydration which is what allowed Scheinfurth to identify caerulea from petals more than 3000 years old.

Drying cut flowers of caerulea in the sun will reduce the petals to a not-so-attractive tan yellow.

There are many, many blue-flowered cultivars that I could find with substantially darker and more vibrant blues: *cultivar list*

These cultivars are derived from the base blue species capensis, nouchali, colorata, gigantea, micrantha, and of course caerulea.

The blue-purple micrantha is particularly important because it can reproduce vegetatively from *bulbils*, a highly desireable quality for plant breeding.

When flowers are not available, the leaf structure can be used to (mostly) identify a caerulea or at the very least rule out some potential species.

The leaf margin of caerulea is entire or smooth.

Though the edges closest to the wedge can have an irregular wavy appearance.

Dentate or crenate (toothed) leaves are common in Nymphaea spp. and are a sign of something other than caerulea.

This is one of the quickest ways to disqualify a potential plant.

The leaves are solid green on the top and green with dark flecks on the underside.

Caerulea's leaves are sort of mid-range in size for Nymphaea with an upper limit of 30-40cm.

The smallest lily *thermarum* produces leaves that are only 2-3cm wide at maturity.

And the largest Nymphaea leaves belong to *gigantea* up to 75cm across.

Though obviously as seedlings the leaves will be smaller: 2-3mm long for the first true leaf on caerulea.

But even during the mature flowering period, leaves can vary in size according to soil fertility and growing space.

Likewise, there are also a number of purple flowers that can appear more blue depending on the age and maturity of the plant, the available light, the fertility of the growing media, and of course, the subtle shifting of the wavelength response of the red cones of your host's eyes.

The color of a single flower can "bleach" in the sun: appearing more purple on the first day of opening and getting progressively lighter blue into the second and third days.

That's why it is important to examine a potential caerulea over a long time period.

A single photo is not necessarily enough to identify a waterlily definitively.

Though sometimes a single photo is enough to disqualify a potential identification.

Furthermore, if a single plant seems to vary considerably during the growing season, that might be evidence of *heterogenomicity*, more specifically, hybridization.

Uneven phenotypic expression is more likely to arise due to the different genes of the parent species, especially in self-compatible waterlilies like caerulea where sexual reproduction tends toward uniformity not divergence.

There are even some *chimeric* waterlily cultivars out there, but that's a different story altogether.*Nymphaea 'wanvisa'*

The sepals of caerulea are also quite interesting.

They are streaked with dark purple to black lines and specks.

As I touched on in my Nelumbo nucifera germination video, there's a lot of crosstalk between lilies and lotuses.

This is driven not by morphological similarity, but by confusing nomenclature in the amateur and professional communities alike.

Most water garden stores sell these two genera and they are often confused despite being radically different, genetically.

However, they are easily distinguished by leaf structure.

Nelumbo have whole leaves with special hydrophobic structures on their upper leaf surface that repel water.*water repel nelumbo*

Nelumbo can produce emergent leaves that rise well above the water's surface.

But they also produce floating leaves early in their grow cycle so that isn't a 100% guaranteed identifier.

Nymphaea have split leaves that look a bit like pacman that mostly float on the water's surface.

Large, notched leaves are also common in Nuphar species like spatterdock *Nuphar advena*, but their flowers are very different so they are unlikely to be confused with Nymphaea.

So in summary:

You want this:
*caerulea flower*

Not this:
*capensis flower*

This:
*caerulea flower*

Not this:
*nelumbo flower*

These leaves:
*notched leaves*

Not these leaves:
*whole leaves*

These dried flowers:
*caerulea flower*

Not these dried flowers:
*capensis dried flower*

This fading color:
*caerulea fading petal color*

Not this saturated color:
*stellata*

This plant size:
*caerulea*

Not this plant size:
*thermarum*

This many petals:
*caerulea petal count*

Not this many petals:
*capensis petal count*

This color:
*caerulea sky blue*

Not this color:
*micrantha*

This leaf margin:
*caerulea margin*

Not this leaf margin:
*capensis margin*

These sepals:
*spotted sepals*

Not these sepals:
*green sepals*

These petals:
*caerulea petals*

Not these petals:
*capensis petals*

These stamens:
*caerulea thick stamens*

Not these stamens:
*gigantea stamens*

The features listed so far are usually sufficient to properly identify a Nymphaea caerulea.

But because I like to torture you, dear viewer, with a deluge of facts, here is an exhaustive list.

A botanical identification guide isn't complete without a long paragraph of highly specific anatomical terms, after all.

This is taken directly from Conard 1905 pg 141-146:

Note that many of these features are shared by other waterlilies especially in the brachycerus subgenus.

Only Nymphaea caerulea will have all of these features, however.

Flowers 7 to 17 cm. across, light blue, with a faint and characteristic sweet odor, open on 3 days from 7.30 a. m. to 12 m. (4 days, 8 a. m. to 2 p. m. Casp. 1877).

Bud distinctly conical, with straight sides, obtuse, abruptly contracted below to the receptacle, 7 cm. long by 2.5 cm. in diameter at base.

Receptacle nearly three times as wide as peduncle, spreading out at about 45° from the vertical, pale purplish green.

Peduncle terete, 0.6 to 0.8 cm. in diameter, 18 to 38 cm. long, most slender about 1.25 cm. below flower, smooth, dull brownish-green; main air-canals 6, surrounded by a circle of 12 smaller ones.

Sepals 4, broadly lanceolate, breadth:length = 1 : 2.8 to 4.7, the sides nearly straight in upper two-thirds, somewhat converging below to the broad base ; apex rounded.

Outer surface dark green, thickly flecked with purplish-black dots and lines most dense near margins of sepal and midway of length ; the green ground-color assumes a yellowish tint near base of sepal.

Seven longitudinal veins can be seen by looking through the sepal at the light.

Inner surface dull white, tinged blue on midline near apex, greenish and veiny and semi-translucent in lowest three-quarters of length.

Petals 12 to 20, of moderately firm texture, opening about "30° above horizontal, about as long as the sepals.

They stand in 3 series: first, a whorl of 4, alternate with the sepals ; second, a whorl of 8, one on each side of each outer petal ; third, a whorl of 8 alternate with the second, but usually imperfect, consisting of only 2 to 5 petals on one side of the flower, rendering it so far unsymmetrical.

Outermost petal narrowly elliptic-lanceolate, obtuse, with rather broad insertion, not at all concave; outer surface colored on lower half and on the midline dark green with black spots exactly like the sepals ; one-third of width at margin on each side, above, colored pale blue ; inner surface white on lower half, becoming translucent and 7-veined at base, shading above to a pale sky-blue at apex and on upper margins.

Petals of second whorl shorter than those of the first, rhombic-lanceolate, narrowed at apex and base, 5-veined below, white on the lower third, pale blue above, pure sky-blue at apex, the blue and white shading together insensibly, the latter predominating in two-thirds of length on inner surface of petal.

Petal of third (innermost) whorl linear-lanceolate, obtuse, blue at apex; outer surface with white margins in lower three-fourths of length, the blue continuing half way down the midline ; on inner surface, white prevails on lower five-sevenths of length.

Stamens 50 to 73, sometimes appearing inserted without order, sometimes indistinctly spiral, often in about 16 vertical ranks of 3 to 5 stamens each.

Outermost stamens with short and rather broad filaments and long acuminate anther with two long, nearly parallel anther cells and proportionately long, acute, 3-angled appendage, one angle pointing inward ; blue at tip and half-way down, yellowish-white below.

Median stamen has short, broadly elliptic filament, very long parallel anther cells, and short appendage ; anther and filament bright yellow, only the appendage blue.

Innermost stamen bright yellow all over, short, stout ; anther broader and longer than filament; no appendage. Ovary nearly hemispherical (e. g., 1.9 cm. in diameter by 0.95 cm. high ; 0.4 cm. by 0.24 cm.).

Carpels 14 to 21 ; styles short (0.3 cm. long by 0.08 cm. in diameter), fleshy, nearly erect, subacute, concave inward, all alike, pure yellow, papillose up to about 0.08 cm. from apex, the papillose area ending roundly.

Stigma nearly flat, bending upward on the styles, yellow.

Axile process rising abruptly from the stigma, broader than high (height: breadth = i : 1.5 ;== 0.24 cm. : 0.38 cm.) and somewhat conical in shape, with obtuse tip, of a whitish color.

Fruit large, round (4.5 to 6.4 cm. in diameter by 2.5 to 3.8 cm. high), truncate above, with deep radiating fissures between the carpels, flattened or even excavated beneath around the peduncle, of a pale green color, becoming translucent and brownish, crowned with the hard, slightly enlarged styles, and surrounded by the sepals and outer 4 petals, all of which are dark green and spotted as in the flower.

The peduncle makes a large, rude spiral turn, holding the fruit still erect but with its base nearly or quite resting on the earth.

Seed ellipsoidal, acuminate at the hilum, 0.17 cm. long by 0.12 cm. in diameter, dull olive brown ; surface marked with about 14 interrupted longitudinal lines of minute hairs ; raphe evident, not prominent.

Aril longer than the seed.

Leaf of mature plant very narrowly peltate (1:14 to 16, Casp. 1877) , ovateorbicular to orbicular, 30 to 40 cm. in diameter, soft, thin and quickly withering, slightly wavy or sinuate in the basal half, apex slightly emarginate, dark green and obscurely veiny above, color darker over insertion of petiole.

Under surface paler green, with numerous small dark purple blotches, which are larger near the midrib than at the periphery ; margins purplish, shading from dark redpurple at the extreme edge to green, the transition taking place in the course of about 1 cm. near sinus angles, in about 2.5 cm. at apex of leaf.

Veins prominent out to the fifth grade; primary nerves 6 to 10 on each side of leaf.

Petiole attached by quite a strong " collar."

Length of principal area: radius of leaf 1 : 1.3 to 1.7. Sinus usually closed; depth: length of leaf = 1 : 2.7 (= 13.5 cm. : 35.7 cm.); margins doubly curved, convex and overlapping above, separating about 2.5 cm. from periphery of leaf and becoming parallel ; angles subacute, slightly produced, about 0.6 cm. apart.

Petiole terete, or flattened near the leaf, about 0.6 cm. in diameter, dull brownish-green ; with 2 larger upper air-canals, and 2 smaller ones below, and a ring of 12 still smaller ones outside.

Stipules smooth, fused at base, short, distant above, acuminate, very acute ; 1.9 to 2.2 cm. long, 1.3 cm. wide at base; free portion i.i to 1.6 cm. long, 0.5 cm. wide; tips 0.9 to 1.2 cm. apart.

Phew!

There you have it: A constellation of characteristics that define Nymphaea caerulea.

Now on to the reasons why you shouldn't trust anything I have said...

First and foremost: No one seems to agree on the phylogeny of caerulea.

Some taxonomists call caerulea a variety of nouchali, not as a species unto itself.

In that case, the plants belonging to the nouchali designation could have white, pink, or blue flowers.

The leaves can have dentate margins with a dark purple underside.

If you can't tell by the descriptions given in this video, I don't subscribe to that hypothesis.

Primarily because the blue flowered nouchali has 2n=56 chromosomes and caerulea has 2n=28.

Not that this is absolute evidence of antonomy.

Plants are more tolerant of chromosomal differences than animals.

Anyway, because Nymphaea redily hydridize and have been doing so for millions of years, strict taxonomy based upon sterility of offspring just doesn't work.

So we are stuck with the old morphology based classification, which I have presented in this video.

Similarly, the traits presented here might be overly specific.

I only have a single specimen of what I believe to be Nymphaea caerulea.

All of the images used in this video are of my specimen alone.*"Epony"*

I am reasonably sure, based on the literature, that these traits are not overly specific.

But again, this is all rather fluid.

Just know that this is an active area of research, with more reliable molecular evidence coming out all the time.

Secondly: There are a few features that I did not talk about in this video but which are defined in the literature.

I'm not about to dig up my only plant to show you cross sections of the rhizome for example.

Likewise, when I can afford a decent microscope, I'll have some microscopic morphology and maybe some cytology to further confirm this identification.

But I still might find something on my plant that contradicts the literature ruling out caerulea as an id.

Finally, the question of medicinal value of caerulea in relation to other species:

I have no idea what kind of Nymphaea has the highest concentration of active principles.

I suspect, the ancient Egyptians didn't either.

They found some local plants that had some medicinal properties.

Later they drew some pictures on walls and occasionally buried their dead with a couple of petals.

The most potent Nymphaea might very well be something that the ancient Egyptians didn't have access too.

Indeed, the all-white species *Nymphaea ampla* is depicted in Mayan art in a medicinal or spiritual context in the same way that caerulea was shown in Egyptian art.

In fact, I have reason to believe that the the original association of caerulea with ancient Egyptian rituals by Schweinfurth in 1883 was incorrect.

Or at least what we now call caerulea.

For whatever reason, caerulea entered the public consciousness as the one-and-only psychoactive species with its blue color used as the primary marketing tool for vendors ever since.

Even when they aren't actually selling caerulea.

This video is about identifying a species, not what that species will do for you if you eat it.

So if you have any questions related to the morphology or disagree with me about it, don't hesitate to comment.

A request before I go: Please don't put links to specific products in the comments asking, "Is this a real blue lily?"

The point of this video is to teach you how to identify caerulea yourself.

I hope this video was enlightening.

Thanks for sticking around.


"On the other hand, thofe of the nymphaea caerulea have their edges fcarcely finuated; their lobes are more pointed, and commonly divergent. The inferior furface exhibits ribs fcarely fenfible, the principal ones of which only are fomewhat prominent: the reft being concave and lefs elevated than the difk. The petioles of thefe leaves are exceedingly rough."