Kelu

Kelu is a large sessile weed endemic to Velor’s seamarshes with an average height of three meters, depending on water depth. A plant of three parts, Kelu can be divided up into an anchoring root system, the subsurface stem and a large frond which can be as much as a meter in length.
Kelu (pronounced Kel-ew) derives its name from the Galen, whom appears to also have had some small interest in the plant. Normally translated as ‘Old thread’ “Kelu” is in fact mathematical shorthand describing the number of days in a period of two billion years, though Velorians have as yet been unable to explain why their gods chose to ascribe this name to a plant.
The most reasonable explanation would appear to be that Kelu is simply very old; nuclear DNA sequencing has confirmed its form has remained unchanged for an extremely long time, possibly as much as two billion years. 
Like many water plants, Kelu has no true support structure and instead derives strength from its stem of interlocked gas bladders. These bladders also serve as the plant’s primary deterrent against attack as the membranes are extremely fragile and the sulphurous gas they contain is noxious enough to dissuade even Velorians from venturing near. 
Above this, the frond emerges from a ring of broad leaves and is fairly remarkable in that it is a sensing organ. Delicate hairs which emerge from every part of the frond are used to detect oncoming storms while interspersed chemoreceptors give the plant a limited sense of smell. When a storm threatens, the plant relaxes sphincters in its bladders, releasing much of its gas and submerging the frond, where it will be protected from the storm. Upon detecting the release, other plants will quickly follow suit with the unfortunate consequence of creating a gas cloud which can still be offensive even thirty kilometres downwind, and is the primary reason why there are so few settlements around the seamarshes. 
As a sessile plant, Kelu has a variety of leaves which emerge directly from its stem, however owing to the general murkiness of the water in which it lives, only a fraction of its energy is derived from photosynthesis. As a result, Kelu’s leaves have become adapted to a variety of purposes.
The uppermost leaves are broad and float on the surface. These are primarily used for photosynthesis and gas exchange, although they have a secondary function as floatation aids when the plant has sustained damage to its stem. Owing to the fact that these leaves are topped by the plant’s feather like frond, they are colloquially known as Kelu’s Cap.
Subsurface leaves are also photosynthetic, but the energy recovered is so minuscule as to render this a vestigial function. Instead long rigid leave interlace with those of neighbouring plants and create a physical barrier against intrusion into the patch by larger animals.
Between these guard leaves, many thousands of filaments grow out of specialised bladders. Their function is to trawl the currents, ensnaring prey and drawing it back into the main body, where the bladder closes, rapidly fills with gas to stun the prey before developing into a highly efficient single use stomach.
Kelu is hermaphroditic, but does not self-fertilise. Instead sexual material, in the form of a gelatine bound mass, is transported around the community via highly specialised variants of the feeding filaments. These filaments, upon making contact with similar filaments from neighbouring pants carefully exchange the sperm, whereupon it is drawn into nurturing sacks, much in the same way prey items are. Kelu is capable of recognising material from plants it has coupled with before and apparently remembers if it has done so in the recent past, rejecting the sperm if this is the case in order to preserve diversity. However the material is not discarded but rather exchanged again and can travel considerable distances before finally being accepted.
Upon being accepted, the receiving chamber will bud off, forming a self sustaining polyp like organism. This polyp, which is arguably a separate ‘midwife’ life form rather than simply an early stage of Kelu development, will quickly distance itself from its parent although only in rare cases will it go far beyond the local patch.
The midwife can live for up to two weeks and will never settle within 20 centimetres of another Kelu so as to give the young plant room to grow. Upon settling, the midwife will bury itself in the mud and spend the remainder of its life nurturing the young plant by filtering in nutrients while serving as a barrier to infection.
Perhaps the most remarkable aspect of the Kelu is that it is, if not sentient than certainly sapient and clearly able to not only perceive the world around it, but react in intelligent ways, such as refusing to catch prey which it knows it cannot digest. The definitive example however, came when a manufacturing company decided to farm the Kelu as a cheap source of sulphides and thiols.
The company quickly found that, while crop yields were initially high, no new plants were growing to replace the ones harvested. It was only after an exhaustive, yet fruitless search for chemical contamination, that someone made the – at the time – ridiculous suggestion that the plants simply weren’t happy laying seeds in an area that was bad for them.
This notion was naturally ridiculed until it was noticed that while Kelu density had fallen markedly in the area being farmed, it had increased by a reciprocal margin in the direction immediately away from the area of activity. Far from merely stopping reproduction, the plants had chosen to plant their offspring away from danger.
While this was remarkable, it was not until further experiments were performed on living specimens that the truth became clear; Kelu could not only be stressed by involuntary gas extraction, but the plant would actually refuse to reproduce, to the extent of ignoring even sperm that had been artificially inseminated into a reproductive sack.
The apparent contradiction between observed behaviour and science’s inability to discover even the most rudimentary form of brain was the source of both humour and consternation for centuries until the answer was finally uncovered.