Hypericum carinatum
Subshrub or annual (?) herb (0-2-)0-3-0-7(-2) m tall, erect, 1-stemmed or branching at the base, with lateral branches erect or ascending, numerous or absent, not usually naked below. Stems red-brown to green, persistently 4-lined, ancipitous when young, cortex persistent (always); internodes 15-65 mm long, shorter to longer than leaves. Leaves sessile, suberect or spreading; lamina 15-45(-50) x 5-15 mm, narrowly oblong or elliptic-oblong to ovate-lanceolate or oblanceolate, margin plane or usually basally to wholly recurved, paler beneath, not glaucous, chartaceous; apex acute to rounded, base cuneate to cordate, decurrent-amplexicaul, forming deep V, free; basal or near-basal veins 3-5, midrib with numerous to 2 pairs of branches, tertiary reticulum dense, sometimes obscure; laminar glands dense to rather sparse, obscure, not prominent. Inflorescence l-7(-17)-flowered, dichasial/monochasial, with- out accessory branches, with lateral branches from up to 8 nodes below, the whole narrowly cylindric to narrowly (or rarely broadly) pyramidal; primary pedicels 1.5-4 mm long; bracts and bracteoles linear-lanceolate to linear-oblong. Flowers (12-)15-25 mm in diam., stellate; buds ellipsoid, subacute. Sepals 5-11 x l-2(-2.7) mm, equal, scarcely imbricate, linear-lanceolate to lanceolate, acute to subacuminate; veins 3-7, only midrib or sometimes all becoming prominent; glands linear. Petals yellow to orange, 7-16 x 3.5-6 mm, c. 1-4 x sepals, oblanceolate or oblong-oblanceolate to obovate; apiculus acute; glands linear, distally striiform to punctiform. Stamens 70-80, obscurely 5-fascicled, longest 3.5-5.5 mm long, 0.35-0.5 x petals. Ovary 2-3 x 1.5-2 mm, broadly ovoid; styles 5(4), 2.5-3 mm long, 1-1.25 x ovary, spreading; stigmas clavate to narrow. Capsule 4.5-6 x 4.5-5 mm, broadly ovoid to subglobose, shorter than or equalling sepals. Seeds c. 0.5 mm long; testa ribbed-scalariform.
Damp or shaded grassland or stony places; 100-1900 m.
Brazil (Paraná, Santa Catarina, Rio Grande do Sul), Paraguay, Argentina (Salta, Formosa, Misiones, Corrientes, Entre Rios, Buenos Aires, Córdoba), Uruguay.
H. carinatum is related to H. campestre subsp. campestre, a few specimens from Paraguay (e.g. Rojas 8609a (K)) and Brazil, Paraná (e.g. Kummrow 1824) being somewhat intermediate. Usually, however, the markedly decurrent leaf base and relatively broad leaves suffice to distinguish H. carinatum from all other species of the H. brasiliense affinity except H. anceps. The Paraguay/Paraná area is also the one whence the two main trends in H. carinatum diverge. In one (H. carinatum sensu stricto), the internodes remain short, the leaves narrow, and the inflorescence short (1-5 fertile nodes) and pyramidal; in the other (H. altissimum, H. megapotamicum, H. paraguense ?), the internodes become elongated, the leaves broad, and the inflorescence long (to 8 nodes) and cylindric. Although both forms may occur in the same area (e.g. Rio Grande do Sul), they are linked elsewhere by intermediates that prevent the recognition of infraspecific taxa. At the southern extreme of the first trend are Uruguayan and Argentinian plants with smaller flowers and leaves and a more diffuse habit, which I have distinguished as H. anceps Larranaga. Towards the western extreme of the same trend, in Paraguay, are plants which, except for the 5- styled ovary and subglobose fruit, are similar to H. silenoides.
From Keller's key the type of H. paraguense R. Keller is an annual herb with oblong obtuse leaves, a subglobose capsule, and styles about as long as the capsule, a description that can apply only to H. carinatum. No specimen in Geneva (G) agreeing with this description has been annotated as H. paraguense by Keller; indeed most of them have been annotated by him as H. brasiliense var. punctulatum. Of the remaining collections utilised by Keller in writing his 1908 paper, all except those at Berlin (B) and Brussels (BR) have been searched by me without success; and according to Bamps (in litt., 1988), there is no specimen labelled H. paraguense by Keller in Brussels. If the type was in Berlin, it probably no longer exists. It seems likely however, that Keller was giving specific rank to a taxon based on the specimens that he had wrongly included in H. brasiliense var. punctulatum in 1903. Of the three collections cited in that paper, I select the only one to agree fully with Keller's key: Paraguay, Concepcion, prope Concepcion, September 1901 (fl & fr), Hassler 7395 (G!- lectotype).