identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
9341782B6A11558CA19BF8EBCDD5230D.text	9341782B6A11558CA19BF8EBCDD5230D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Lathyrus platyphyllos (Retz.) W. D. J. Koch	<div><p>Lathyrus platyphyllos (Retz.) W. D. J. Koch, Syn. Fl. Germ. Helv. ed. 2: 443 (1843)</p><p>≡ Lathyrus sylvestris var. platyphyllos Retz., Fl. Scand. Prodr., ed. 2.: 170 (1795).</p><p>≡ Lathyrus sylvestris subsp. platyphyllos (Retz.) Hartm., Sv. Norsk Excurs. - Fl. 102 (1846).</p><p>≡ Lathyrus sylvestris f. platyphyllos (Retz.) Nordh., Norsk Fl. [Nordhagen]: 381 (1940).</p><p>Holotype.</p><p>t. DCCLXXXV in Flora Danica s. d. (1787?). The protologue of Lathyrus platyphyllos refers exclusively to this illustration, with no mention of any specimens. Following ICN Art. 9.1–9.2 and in line with the guidelines discussed by McNeill (2014), this plate is treated here as the holotype. While it is theoretically possible that Retzius consulted additional, uncited elements, this illustration represents the only verifiable original element.</p><p>Diagnosis.</p><p>Species resembling Lathyrus sylvestris in general habit, but differing in several vegetative characters:</p><p>Leaflets of mid-stem leaves are considerably broader (up to 40 mm wide), with a length-to-width ratio of ca. 3.5–4 (– 5): 1 (vs. ca. 8–9: 1 in L. sylvestris). Leaflet apices are usually broadly rounded to truncate or sometimes slightly emarginate and mucronate (Figs 4, 5, 7), rather than sharply acute and long-tapering (Figs 13, 14). Stipules tend to be slightly broader, reaching up to 4 mm in width (vs. typically ≤ 2 mm in L. sylvestris) and the stem wings are likewise wider, up to 3 mm (vs. rarely exceeding 1 mm in L. sylvestris) (Fig. 6).</p><p>Revised herbarium material.</p><p>(see Verloove et al. (2025), Suppl. material 1: table S 1).</p><p>Notes.</p><p>Within the Lathyrus sylvestris - latifolius complex, numerous diagnostic characters have been proposed over time, the taxonomic value of which has often proven limited. Variation in stem and petiole wing width, for instance, may occur even within a single individual. Similarly, the relative length and equality of the calyx teeth — whether approximately equal or distinctly unequal — appears highly variable and unreliable for diagnostic purposes. Calyx teeth tend to be shortest and least unequal in L. sylvestris, but exhibit a gradual transition towards the other species.</p><p>In its typical form, L. heterophyllus is readily separated from the remaining taxa by the presence of two (rarely three) pairs of leaflets on most leaves, particularly those of the mid- and upper stem, whereas the other species consistently bear only a single pair.</p><p>Unijugate forms of L. heterophyllus ( ‘ var. unijugus ’) have long complicated the delimitation of L. platyphyllos . Both are exceedingly similar in vegetative and floral morphology, as already noted by Koch (1843). According to Sell and Murrell (2009), the only reliable distinguishing character lies in the relative width of the stipules compared to the stem — an admittedly labile trait within this complex. Gams (1924), in Illustrierte Flora von Mitteleuropa, likewise cited this feature, together with several others of even lesser diagnostic value. Examination of Swedish specimens with unijugate leaves confirms that the stipules are conspicuously broad, consistently exceeding the stem in width and that the hilum of the seed encircles at most one-third of the seed circumference. This latter feature, in particular, appears stable and may, therefore, retain some discriminative significance.</p><p>By contrast, L. latifolius differs clearly from both L. sylvestris and L. platyphyllos in its larger, more vividly pink flowers, the style being hairy over a greater portion of its length and its broad stipules (up to 15 mm wide, consistently broader than the stem). Its calyx teeth are strongly unequal, the longest clearly exceeding the calyx tube; the hilum of the seed likewise encircles at most one-third of the circumference.</p><p>Taken together, L. sylvestris and L. platyphyllos are readily separable from L. heterophyllus and L. latifolius, yet they remain much more difficult to distinguish from one another. Only a few characters appear consistently reliable: chiefly, the relative width and shape of the mid-stem leaflets and their apices, as well as the tendency for slightly broader stipules and stem wings in L. platyphyllos .</p><p>Distribution.</p><p>As Lathyrus platyphyllos is a scarcely known species, information on its natural distribution remains limited. It was described from Denmark and historical sources additionally indicate that it is native to Central Europe (Germany, Austria, Czechia and Switzerland) and possibly also to eastern France (Jura), Poland (Silesia) (Gams 1924) and northern Italy (Fiori 1925). According to Gams (1924), the species is occasionally cultivated as an ornamental. The natural distribution of L. platyphyllos is entirely embedded within the broader range of L. sylvestris, which is much more widespread across Europe.</p><p>In Belgium, by contrast, L. platyphyllos is almost certainly not native. It was first reliably recorded only in 1943 and is confined to habitats subject to varying degrees of human disturbance, most commonly along railway lines or on disused railway grounds. The species is naturalised in a few widely scattered localities, particularly in the broader regions of Antwerp and Ghent — where it may be locally frequent — and in central West Flanders, with additional, more isolated populations elsewhere in the country.</p></div>	https://treatment.plazi.org/id/9341782B6A11558CA19BF8EBCDD5230D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Verloove, Filip;de Backer, Sander;Bawin, Yves;Groom, Quentin;Leliaert, Frederik;Meeus, Sofie;Janssens, Steven B.	Verloove, Filip, de Backer, Sander, Bawin, Yves, Groom, Quentin, Leliaert, Frederik, Meeus, Sofie, Janssens, Steven B. (2026): Morphological and genomic data from Belgian naturalised populations reinstate the enigmatic Lathyrus platyphyllos (Fabaceae) as a distinct European species. PhytoKeys 273: 255-279, DOI: 10.3897/phytokeys.273.180869
