Dactylis
The Dactylis is a large and somewhat rare Tyranid. It takes the form of a large slug-like being, sitting at the back of the front lines in a way uncommon with most Tyranids. It uses its two long and multiple-jointed arms to grab parasites called Bile Pods feeding off glands on the back of its cranium and fling them at the enemy, making distinct whip-like cracks with its limbss it releases them. These Bile Pods then float to the ground much like Spore Mines do, moving around in search of a target. Initial forms of these Bile Pods were more or less identical to Poison Spore Mines, but later versions of the Dactylus had spore-generating colonies that create a variety of payload.
Originating in Epic, the Dactylis got itself a set of rules in Chapter Approved 2001 for 3rd edition 40k. The creature is very useful if you are considering to use a brood of Biovores. Cheaper than two of those with the full set of Spore Mines, the Dactylis has two Spore Mine Dischargers that it can shoot twice in one turn for a significant output. It is also quite tough with T6 W3 and a neat 2+ save, making it quite a bit more durable than a Biovore.
However the looks and function of the Dactylis has been overall retconned now. This time, the Dactylis are Biovores on Steroids and are large enough to be considered as a form of Bio-Titan. What, you would think that the Exocrine should fill in that list. Anyways, while its looks and function may differ back in Epic, its role is still the same in that of a Tyranid super-heavy artillery unit.
The Dactylis are nowadays portrayed as a humongous Biovore as previously mentioned. Their forelimbs are now thick and gorilla-like that is covered in extremely heavy bone-plates rather than its previous long, dangly arms. The Dactylis now also spots a more armored and well-rounded head, visible tail, a scything talon on its secondary arms, a ceratopsian-esque head-frill and a EX BAWKS HEUG cannon which fires gigantic Bile Pods.