Although the leaves look similar, the image appears to show blooms more like those of Shooting Star Hoya (Hoya multiflora)



As seen in images on this page, Hoya coriacea blooms are of a different shape: https://www.google.com/search?...

Looking at the description that accompanied the illustration, it seems that the editor, John Lindley, was unsure if it might be another Hoya. Here's some of what he wrote in April 1839:

"A very pretty stove plant, sent by Mr. Cuming to Messrs. Loddiges, from Manila; it flowered for the first time in August 1838.

The genus Hoya is a large one, the species of which abound in the southern parts of India, and are but imperfectly known to Botanists. Dr. Wright mentions twenty as found in Hindostan and the neighboring islands; to which Dr. Blume adds nine more. The characters of the latter are so very short that it is impossible to ascertain, in the absence of authentic specimens, whether a plant corresponding with those characters is really the one intended; for distinctions expressed in such brief terms may apply to several different species and not be peculiar to one only. For this reason I am in doubt whether the plant now figured is really the H. coriacea, although I perceive no difference between it and Dr. Blume's definition of that species. It is to be hoped that this and all such points will be settled by M. Decaisne, who, fortunately for science, has undertaken the elaboration of the natural order Asclepiadaceæ for DeCandolle's Prodromus."

But wait! There's more! In the next year's volume, Lindley writes:

"1. HOYA coriacea. Botanical Register, 1839. t. 18.
I find that this very rare plant is the Cyrtoceras reflexum of Horsfield's Plantæ Javanicæ, p. 90. t.21. Mr. Bennett, the learned author of the genus, and of the greater part of the work in which it appears, distinguishes it from Hoya by "the great comparative elongation of the whole of its sexual apparatus, which in Hoya is as remarkably depressed. The inner angle of the foliola of the corona staminea, which in Hoya forms a mere tooth incumbent on the anthera, is produced in Cyrtoceras into an erect lanceolate process, twice as long as the anthera, and equal in length to the external horn, at the base of the foliola." It appears that mutilated specimens, "apparently of the same species, or at least of a very nearly related plant, exist among the collections of Father Camel, in the Sloanean Herbarium, (vol. 231.) in the British Museum. They were gathered in the island of Luçon." "From Dr. Horsfield's notes we learn that the Javanese name of the plant is Kappal, and that it grows in various localities in the eastern parts of Java, at no great distance from the seashore." It must not be confounded with the Kapal Kapal of the Philippines, which according to Father Blanco, is the Asclepias or Calotropis gigantea; and at all events is an entirely different plant of the same natural order.

Messrs. Loddiges find the plant so difficult to multiply, that they have not yet succeeded in obtaining a duplicate."

The Catalogue of Life gives Hoya multiflora Blume as the currently accepted name of Cyrtoceras reflexum, so kudos to you!

Edited to add that I've requested that the illustration be moved.