Mitragyna Speciosa, Korth. is the scientific name for Kratom and was originally defined by Pieter Korthals and confirmed and reiterated by George Darby Haviland A Revision of the Tribe Naucleeae (Nat. Ord. Rubiaceae) Originally published in “The Journal of Linnean Society” Feb. 4 1897 p. 65-69
The following description has been translated from Latin by myself with the help of google translators and various online dictionaries:
Obtusely angled branches (greater than 90 degree angles). Leaves 14 cm long, 7 cm. wide, elliptic, abruptly acuminate (tapering to a point), base rounded or subcordata (heartshaped, perhaps with the notch oriented at the bottom?), below the veins pubesentia (hairs? or new growth?), veins 15. Petioles (the stalk that joins a leaf to a stem; leafstalk) 25 mm. Stipulae (stubbles) 2 cm., lanceolateae (Shaped like the head of a lance; tapering from a rounded base toward the apex), sparse pubescentes (hairs), veins 9. Peduncle (the stalk bearing a flower or fruit, or the main stalk of an inflorescence) ternate (terminating? or arranged in threes or in subdivisions so arranged), 3-5 cm. Bracts (a modified leaf or scale, typically small, with a flower or flower cluster in its axil. Bracts are sometimes larger and more brightly colored than the true flower, as in a poinsettia) foliaceae (leafy) 4 cm., petioles (the slender stalk by which a leaf is attached to the stem; leafstalk) 2cm. Corolla (the inner envelope of floral leaves of a flower, usually of delicate texture and of some color other than green; the petals considered collectively) tube 5 mm., extra glober (outside the globe), fauce pilosus (throat hairs?); lobes 3 mm., glabris marginibus revolutis (smooth rolled edges). Fastined stamen (the pollen bearing threads). Style (the tube part of the pistle, in the center of the flower) 13 mm.; stigma (the pollen receiving part at the tip of the pistle) 2 mm. Calycis (the outermost group of floral parts; the sepals) lobes 5, quatuor breves rotundi (four short ones in the revolution), quintus saepe spothulato-oblongus(and the fifth often oblong and spatular in shape); tubi pars superior brevis(the upper part of the tube is short), cupularis (cup-shaped). Bracteoleae (the bracts) 4 mm., subglabrae(beneath the globe). Receptaculum dense hirsutum (The receptacle [the modified or expanded portion of the stem or axis that bears the organs of a single flower or the florets of a flower head] is densly hairy). Fructus costae (fruit ribs) 10, endocarpiis (the inner layer of a pericarp [the walls of a ripened ovary or fruit], as the stone of certain fruits) 4-valvatis (4 enlarged vulvas or ovaries). (Several previous references to the plant by other authers are given. including: M.speciosa, Korth. Obs. de Naucl. Ind. p. 19 (without description).) Variation (a): The leaves have 15 veins. - Borneo. Variation (b): The leaves have 10 veins. - Ins. Phillippinae; New Guinea. Malasia.-Borneo: Banjarmassin (Korthals; Motley, n.1169). Ins. Philippinae: Luzon (Vidal, n.798). New Guinea. Kaiser Wilhelmsland (Hollrung, n.674).
Of this, I have only ever seen one other translation on an Indonesian website came across later, after I translated this. It was quite similar but much more brief.
I think it is worth pointing out that the FDA places a lot of importance on being able to trace back to the original descriptions of plants, but in my opinion, this this brief description lacks enough detail to definitively identify the species. Then again, I’m not a Botanist, but could anyone who has never seen a Kratom plant accurately draw one based on this description? I suppose the description only needs to be unique enough to distinguish it apart from all other similar plants, but it just seems to me that someone should be able to get a sense of what the plant looks like based on the official scientific description of it. Is this it? Maybe a Botanist can help evaluate this further…