Hoya crassifolia Haworth ex Traill 1811

In Supp. Plant. Succ. (1811) 8 Haworth. Hoya crassifolia.

In Transactions of the RHS 7 (1826) 22-23.  J. Traill. II. Hoya crassifolia.  I find this plant only noticed by one writer, to whose work I add the references. H. crassifolia. Haworth in Supp. Plant. Succ. p. 8. A plant of this species was sent to Mr. Reginald Whitley, from China, in 1817, on board the Wexford East Indiaman, and has since been cultivated and increased in his nursery at Fulham. It is very distinct from, and much more robust growth than, any of the others. The stems are strong and woody, thickly covered with small irregular warts, whence the stem-roots are protruded.  The leaves are obovate, very bluntly acuminate, upwards of four inches long, without veins, of a darkish green colour above, pale beneath. The petioles are thick and fleshy, of a purplish green colour, and much flattened above. The plant grows freely in strong heat, but has not yet produced flowers in Europe, it is therefore uncertain whether it belongs to the genus, although it may be presumed so, from its general habit not  differing from Hoya.
            The specific name crassifolia, which had been given to the H. carnosa, by Baron Jacquin in 1811, has been applied to this plant by an inadvertence on the part of the author above quoted, he supposed Jacquin’s plant to be identical with this one, referring it to Jacquin’s figure in his Ecologae. Though the Hoya (Schollia) crassifolia of Jacquin, was published by him in 1811, and was stated in his Ecologae to have been sent to him in England in 1804, yet Mr. Haworth has refereed the plant first introduced by Mr. Whitley in 1817 to it, and has adopted Jacquin’s specific mane, and even stated the large spots on the leaves so conspicuously exhibited in Jacquin’s figure as distinguishing this plant from H. carnosa. The name is objectionable, inasmuch as it may occasion confusion in references, and when the plant blossoms so that it can be fully and perfectly described, it will probably receive some other.

Other literature:

            In General System of Gardening and Botany 4 (1837) 126.  G. Don. 19 H. crassifolia (Haw. suppl. pl. succ. p. 8. exclusive of the synon..) leaves petiolate, obovate, obsoletely spotted, bluntly acuminate, very thick. (woody perennial) Native to the east Indies. Leaves 4 inches long, dark green above, pale beneath. Very like H. carnosa, but the leaves are thicker, more obsoletely spotted . Branches warted, producing roots from the warts, Flowers unknown, Thick-leaved Hoya. Fl.? Clt. 1817. shrub tw.

            In Decandolle, Prodromus Syst. Veg. 8 (1844) 60.  Decaisne. (Species non statis notae) H. crassifolia (Haw, succl. pl. suppl. p. 8 ), foliis oppositis petiolatis subovatis obsolete maculatis praecrassis, floribus umbellatis, petalis truncatis obtussive. Affinis H. carnosae at foliis obtusioribus crassioribus, maculis marginis obsolentis pallescentibus. (woody perennial) in India. Schollia crassifolia Jacq. eclog. pl. t. 2. Traill l.c. p. 22.

Translation: leaves opposite petiolate somewhat ovate obsoletely spotted, flowers in umbels, petals truncate obtuse. Related to H. carnosa with foliage more obtuse, much thicker spots paler disappearing near the margins.

            In Flora of British India 4 (1883) 62.  J. D. Hooker. (Doubtful and Excluded Species). H. crassifolia, Haw. Succ. Pl. Suppl. 8; Dcne. in DC. Prodr. viii, 640 Schollia crassifolia, Jacq: Eclog. t. 2; Traill, in Trans Hort Soc. vi 22; from India; with leaves described as excessively thick, obsoletely spotted, petals truncate or obtuse,  flowers unknown. Wight (Contrib. 38) refers it to the Chinese H. carnosa, Br. which it would supersede.

Hoya crassifolia Ridley 1912

Type description:

            In Journal of the Royal Asiatic Society, Straits Branch 61 (1912) 30-31.  H. Ridley. Hoya crassifolia, n. sp. Stem rather stout with rugose often pale bark rooting, profusely. Leaves very coriaceous ovate acuminate slightly cordate at the base, margins undulate and minutely irregular dentate, nerves very inconspicuous 3-4 pairs at an acute angle, midrib inconspicuous 6 inches long 2½ inches wide, petiole very short and thick. Peduncle 1½ inches long rachis ½ inch long with elliptic scars, pedicles slender ¼ inch long, hairy with long rufous hairs. Sepals small linear lanceolate acuminate. Corolla half an inch across pink, lobes triangular cuspidate with a long point, villous with long white hairs on the edge, Corolla scales, lower lobes long thick blunt not smooth and spining, upper ones short erect about half as long triangular acuminate. Staminal column short thick appendages long linear acuminate thin membranaceous and translucent white.
            Perak: Tapah on trees on the Temoh Road (Ridley 14059). A most remarkable plant with its hard stiff leaves roughened with short tooth-like processes at the edge, hairy pedicels and long thin stamen appendages.

It seems to me Ridley or the publishers left out the corolla description and under corolla describe the corona. See H. caudata var. crassifolia in Flora of the Malay Peninsula. The name in untenable since it had been previously used.