Lupinus austrorientalis C. P. Sm. Sp. Lup.

Planchuelo, Ana María, 2022, New varieties and synonyms of Lupinus species (Fabaceae, Faboideae) of Northwestern Argentina, Phytotaxa 566 (2), pp. 143-170 : 159-160

3. Lupinus austrorientalis C. P. Sm. Sp. Lup. : 182 (1940). Tables 1 &, 2 (third columns). Figs. 3 & 4 C, D, E .

Plants with bushy architecture and with basal and apical branches, (40–) 50–60 cm tall. Indumentum on stems and petioles with appressed 0.9–1.3 mm long hairs becoming yellowish-golden in herbarium specimens, and with a dense undercoat of curly canescent 0.3 mm long hairs, hiding the surface. Stems 8.0–11.0 mm dia., ligneous and hollow but herbaceous and subfistule in apical branches; internodes 2–4 (–6) cm long. Leaves palmately (6) 7–8 foliolate; stipules (5–) 7–12 mm long, tomentose dorsally, free subulate tips (4.0–) 5–9 (–10) × 1.0– 1.5 mm; petioles 5–9 cm long, about 1½–2 times the length of the leaflets, shorter above, persistent after the leaflets abscises, pubescence as stems; leaflets oblanceolate, 3.5–4.5 (–5.0) × 0.8–1.0 (–1.2) cm, youngest conduplicate, the older complanate with adaxial face covered with appressed hairs all over the surface in the typical variety, mainly glabrous, sometimes with few hairs on the margin or hairs scattered all over the surface in one variety, and with more dense indumentum all over the surface in the third one; all the varieties with abaxial face covered with semi-dense to dense indumentum of long adpressed hairs, tips obtuse to rounded, mucronate. Peduncles 4–7 cm long, hollow and pubescent as stem. Inflorescences terminal racemes but sometimes appears lateral because one of the lateral branch grows vertically, 10–16 (–18) cm long with verticillate to sub-verticillate flowers; bracts lance-subulate or narrowly lance-triangular, deciduous or tardily deciduous, (4–) 5–7 × 1.2–2.0 mm covered with long and short curly hairs dorsally; bracteoles triangular or linear to filiform, 1.0–2.0 × 0.1–0.5 mm, attached 0.8 mm below the lips of the lateral sinuses; pedicels 4–5 mm long at anthesis, 6—8 mm long in fruiting with curly hairs. Flowers (10.0–) 11–13 (–14.5) mm long; calyx with short straight and curly hairs outside, base slightly gibbous above, lower-lip lance-oblong or lance-triangular 6.5– 8.0 (–9.0) x 2.0–3.0 mm the tip acute sometimes truncate or erose almost dentate, upper-lip (5.0–) 6.0–8.0 (–9.0) mm, the lobes (2.5–) 3.0–4.0 × 1.5–2.0; lips connate 1.0–2.0 mm; banner orbicular 9.0–10.0 × 9.0–10.0 mm or wider than long, constricted below with tips slightly emarginate, 11.0–13.0 × 12.0–13.0 mm, depending of the varieties, glabrous or with few hairs distally along the dorsal crest; wings 9.0–11.5 × 6.0– 6.5 mm or 12–13.5 × 8.0– 8.5 mm depending of the varieties, all including the 2 mm long claw, lobe above the claw 2–2.5 mm wide; keel glabrous, 3.0–4.0 (–4.5) mm wide in the middle, the angle 90°–95°, acumen very slender; ovary with 5–7 ovules. Legumes (2.5–) 3.0–3.5 × 0.65–0.80 cm, densely sericeous. Seeds with oblong contour 5.5–6.0 × 3.5–4.0 mm, with seed coat light tan with angle mark around the hilar region when fresh and darker and with dark spots when dry, seed coat structure with reticulatefoveate pattern with 1000 x magnification.

Within the taxonomic characters of this species, it was possible to differentiate three varieties taking into consideration the combination of the indumentum of the adaxial face of the leaflets and shape and size of the banner and wings, as it is shown in the following key.

Key to the Varieties

1a. Banner wider than long, 13.0 mm wide with wings no more than 8.0 mm wide and adaxial face of the leaflets with hairs all over the surface......................................................................................................................... 3.1. L. austrorientalis var. austrorientalis

1b. Banner if wider than long less than 13.0 mm wide with wings more than 8.0 mm wide and adaxial face of the leaflets glabrate but sometimes with few hairs on the margin, or banner orbicular 9.0-10.0 mm wide with adaxial face of the leaflets densely covered with hairs ............................................................................................................................................................................................2

2a. Banner 11.0 × 12.0. Wings 13.5 × 8.5. Adaxial face of leaflets mainly glabrate sometimes with few hairs on the margin................ .................................................................................................................................................. 3.2. L. austrorientalis var. umidicola

2b. Banner orbicular 9.0–10.0 × 9.0–10.0 mm. Wings 9.0–11.5 × 6.0– 6.5 mm. Adaxial face of the leaflets densely covered with hairs ................................................................................................................................................. 3.3. L. austrorientalis var. jujuyensis

Figures

FIGURE 3. Lupinus austrorientalis C.P.Sm. A. Isotype at SI showing the label that says “Leg Pablo Güther, Lorentz, Fl. Arg. 464”. B. Dissected flowers with banners wider than long, typical of var. austrorientalis & var. umidicola (Planchuelo 958). C. Dissected flowers showing the orbicular banner of var. jujuyensis (Venturi 8163). D. Plant growing in Salta, representative specimen Fabbroni 1754 (MCNS) (Photo Fabbroni). E. Detail of inflorescence. F. Detail of flower showing the wide banner that covers the calyx. G. Portion of stem with semi-appressed long hairs and dense curly short hairs. H. Photo SEM (100 x) showing adaxial face of leaflet covered with long hairs, typical of var. austrorientalis and var. jujuyensis, this later more dense. I. Photo SEM (100 x) showing adaxial face of leaflet glabrous typical of var. umidicola. J. Fresh seed in a pod showing the cream color tegument and angle mark around the hilar region. K. mature seed with darker seed coat and angle mark around the hilar region (Photos Fabbroni).

FIGURE 4. Distribution maps of the treated species. The dots indicate the places where representative specimens were collected. Due to the overlap of places, the number of citations is indicated by province in a north-south sequence. A. Lupinus hieronymi C.P.Sm.: Jujuy 4; Salta, 2; Tucumán, 14; Catamarca 4; La Rioja, 1; Córdoba, 9. B. Lupinus burkartianus C.P.Sm.: Jujuy 14; Salta, 6; Tucumán, 16; Catamarca 4; La Rioja, 2. C. Lupinus austrorientalis C.P.Sm. var. austrorientalis: Jujuy 8; Salta, 3; Catamarca, 5; La Rioja, 1. D. Lupinus austrorientalis var. umidicola (C.P.Sm.) Planchuelo: Jujuy, 2; Salta, 13; Tucumán, 4; Catamarca 7; La Rioja, 3; Córdoba, 6. E. Lupinus austrorientalis var. jujuyensis (C.P.Sm.) Planchuelo: Jujuy, 6; Salta, 3.