Squamellaria guppyana flowering in cultivation

[Stone Jaguar]

Greetings after a prolonged absence.

 

After having flowered and hand-pollinated a sexual pair of Squamellaria kajewskii for the past nine months, I was very pleased to note that one of my 15 month-old S. guppyana opened its first flower yesterday. I have included an image for reference. I was struck by how small the corolla is compared to its putative sibling species. The anthers are in contact, almost looking fused and reminiscent of some asclepiad flowers.

 

 

Both of these Solomon island hydnophytines are remarkable for the speed with which they grow in cultivation in my collection. Of the two, S. guppyana is by far the faster; indeed, by a wide margin it is the fastest growing hydnophytine I have experience with.

 

The confusion that surrounds some of the characteristics differentiating these two species, originating with a mixed collection for one of the types, appears to have again crept into the key included in Chomicki and Renner's recent revision of the genus. The floral characters (corolla length x width) they cite are mixed. As is evident here, it is S. kajewskii that has a long, slender corolla tube, not S. guppyana The leaves and caudexes are as described in the paper.

 

 

As an aside, S. guppyana appears to be somewhat intolerant of very bright light when greenhoused. Unlike S. kajewskii and most other hydnophytines in cultivation, I would recommend some shade over the plants to avoid premature leaf drop.

 

Cheers,

 

J

[Todd Kramer]

Jay,

That's fantastic. Your plants are grown exceptionally well. It's fantastic to see the plants thrive in cultivation.

Thank you for sharing.

Todd

[Stone Jaguar]

The caudex on this plant has just expanded very quickly to reveal where entrances will be. The dimples higher up the caudex look like the lower holes did about a fortnight ago. Note from this photo and some of Derrick's images that this species is very strongly "shot-holed", much like larger Hydnophytum ferrugineum and some PNG species. All in all, this is a very interesting and attractive species of hydnophytine.

 

 

J

[Todd Kramer]

Looking fantastic, Jay. Thank you for the information on lighting in cultivation. Cory and have found that H. puffii appreciates lower light levels as well.

[Frank]

Hey Jay, nice flower photos you have here.  My S. guppyanum is getting ready to bloom.  The inflorescence has gotten to the point where it is starting to branch.  No flowers have opened yet.  I came here to see what the male flowers look like - as you know I am hoping for female flowers on my plant.

When I looked at my plant yesterday it had a yellow body at the first branching point in the inflorescence  - the same as in your photo above.  I did not look at it closely - I just wrote it off as a blasted bud.  But seeing your plant here with the same thing made me wonder if maybe it is an extra-floral nectery.  We now know that some of the Squamellarias go out of their way to feed the ants per one of Guillaume Chromicki's recent papers.  Have you examined the yellow bodies and do you have any thoughts on them?   I obviously will have a closer look at the one on my plant when I get back to the greenhouse on Monday.

[Stone Jaguar]

Hi  again, Frank. No, that is just a senescent calyx of a precocious flower. They can hang on for a surprising amount of time on some hydnophytine species (part. in a few Hydnophytum spp.). They are often very confusing when one is peering through the canopy for early fruit.

Please note that the flowers on both my male S. guppyana are very short-lived...perhaps 12 hours? I have noticed that when they first open in the morning, the anthers are in full contact as can be seen above. It is only much later in the day when they separate a small amount that pollen (white/gray) is evident under magnification.

Your experience with squams exactly mirrors mine; by a wide margin they are the fastest growing epiphytic stem succulents that I have worked with. I wonder what Andreas's experiences are in his collection, both with these and the other Fijian species? Perhaps he can chime in here (with photos!!!).

This male is still in a 15 cm basket for scale. Just two years old now. Photo was taken about three weeks back. It has definitely gotten more robust with more sunlight and heat since then. Have just moved it a bit lower down from the roof panels.

[Frank]

Seeds of Squamellaria guppyanum came into cultivation in 2014 and 2015 from the island of Bougainville, just to the northeast of Papua New Guinea.   My two seeds were planted on May 1, 2015 and sprouted promptly.  The first of them started flowering in July of 2017. 

S. guppyanum is dioecious. That means each plant has flowers that make only eggs or pollen (which becomes sperm), never both.  So, if you want to propagate the species by seed you have to have two plants, one male, making pollen in the stamens and one female, making eggs in an ovary.  In dioecious plants both male and female parts may be present in the flower but only the parts of one sex are functional. 

My first-flowering plant is a female.  Here is the flower.  It is very small, only about 5 mm across and about 5 mm long. These photos are magnified using a dissecting microscope and a video camera.

 

Besides the petals the only other obvious flower parts visible here are the stamens.  These are composed of a stalk (called the filament) with a sac on top of it (called the anther) which actually produces the pollen.  The filaments here are just barely visible and are round, thick and silvery looking.   The anthers each have several dark strips on them but are flaccid because they contain no pollen.  The functioning female parts are hidden within the petal tube.

For this second photo I have removed the petals and stamens.  All that is left is the functional female parts:  the rounded ovary at the bottom, with a short style holding up the two stigmas.  The stigmas are sticky and the pollen has to be placed on these by insects who have previously visited a male flower of this plant species and picked up pollen on their bodies.

 

This third photo was taken with a hand-held camera.  It is the inflorescence of the female Squamellaria guppyanum plant in the axil of a leaf with one open flower to the left end.  Wouldn’t make much of a bouquet for your spouse, would it………laughing…..   A number of other developing flower buds are on the inflorescence.

 

 

My second plant of S. guppyanum produced its first flower on November 30, 2017 and much to my relief it is a male plant.  Here are two pictures of that first flower, both again with some degree of magnification.  You can see that the anthers have broken open and released pollen grains.  The faint white lines you see below the anthers within the petal tube are hairs attached to the inside surface of the petal tube.

 

 

I used the pollen to hand pollinate 3 female flowers that were open on my female guppyanum plant that morning.  I am hoping to see fruits forming in a week or two.

[Stone Jaguar]

Great news for the community! I find this to be one of the most attractive of all hydnophytines in cultivation. It combines attractive foliage with a very striking caudex and, of course, the added curiosity of being one of only a handful of hydnophytines known to be dioecious. It is also even faster growing than the very vigorous S. kajewskii and S. imberbis. Unfortunately, I have two large flowering males but hope that we can mix these genes up with Frank's female in 2018 so as to be able to bring this species into broader cultivation in 2019.

Jay