Nicotiana karara M.W.Chase & Christenhusz, 2023

Bruhl, Jeremy J., Andrew, Damien D., Palsson, Ruth, Jobson, Richard W., Taseski, Guy M. & Samuel, Rosabelle, 2023, Nine new species of Australian Nicotiana (Solanaceae), Australian Systematic Botany 36 (3), pp. 167-205 : 197-200

Nicotiana karara M.W.Chase & Christenhusz , sp. nov.

( Fig. 27, 28 .)

Type: Western Australia, Mungada Road to the Karara Mine, near junction with Lochada Road , 280 m, 29°11′42″S, 116°23′16″E, 23 Aug. 2015, Chase & Christenhusz 68280 (holo: PERTH; iso: CANB) .

Diagnosis

Nicotiana karara is morphologically similar to and related to N. rosulata and the N. rotundifolia species complex ( Fig. 1 b ). Like N. rosulata , it has an inflorescence that is pubescent basally but becomes glabrous in the upper portions. Nicotiana karara differs in its more highly branched inflorescences and smaller flowers with didynamous stamens and generally leafy stems (no rosette, but small plants of nearly all species of N. section Suaveolentes , including this one, can form strict rosettes if the plants are small at the time of flowering or grow in full sun; Fig. 28 a ).

Erect herbaceous, annual to short-lived perennial herbs, up to 1.0 m tall, generally with no rosette and numerous large leaves in the basal portion of the stems with few in the upper portions, the major branches from near the base with many side branches in the upper half of the stem. Leaves with narrowly winged petioles, up to 1.0 cm wide and 3.5 cm long, blades 3.4–19.8 × 1.1–7.8 cm (including petiole), ovate-oblanceolate, the apex acute in the basal leaves to acuminate in those higher up, base gradually attenuate, uppermost leaves nearly sessile, bract-like, margins entire, undulate, ciliate, often basally bullate. Vestiture composed of long, somewhat curly, non-glandular hairs on the leaf margins and main veins, dense on the bases of stems, but becoming nearly glabrous on the upper stems, calyces and peduncles densely covered with short, often broadly based glandular hairs. Calyx 0.8–1.0 × 0.10–0.15 cm, one lobe slightly longer and one shorter than the others, the tips acuminate, clasping the floral tube, slightly longer than and surrounding the mature fruit with the apices reflexed. Corolla tube white to pale green, 0.6–0.8 cm long (from tip of the calyx), 0.2 cm in diameter, with a throat cup, the limb white, 0.7–1.0 cm across, the lobes cleft, sometimes with a small mucro, cleft 0.1 cm deep, sinus 0.1–0.2 cm deep, lobe 0.4–0.5 cm long; stamens mostly didynamous, 0.1 cm inside throat of the floral tube and the fifth ~ 0.2–0.3 cm deeper in the tube, all with the filaments 0.2–0.3 cm long. Fruit a capsule, 0.5–0.8 cm long, splitting in four lobes.

Distribution

Found in the eastern edge of the wheatbelt from the Galatea bridge over the Murchison River south to Wubin and nearly as far east as the Weld Range and Lake Barlee in Western Australia ( Fig. 29 ).

Habitat and ecology

In lightly shaded sites under mulga, occasionally in the open or in vegetation on the margins of salt lakes but not in the salt vegetation. In the eastern part of its range, it often occurs near N. salina M.W.Chase, M.F.Fay & Christenh. , but not close to the salt vegetation.

Phenology

Collected in flower September to November.

Etymology

Named for the former Karara Station in the Shire of Perenjori, where the type was collected. The name is of Aboriginal origin, perhaps referring to Acacia bushland ( Acacia tetragonophylla is common in this region and has the common name, kurara; http://www.flora.sa.gov.au/ cgi-bin/speciesfacts_display.cgi?form=speciesfacts&name= Acacia_tetragonophylla ). The species epithet is a noun in apposition.

Chromosome number

Unknown.

Notes

Specimens of Nicotiana karara resemble those of N. rosulata and have been confused with the latter, but the flowers are generally smaller. Plants of N. karara are not rosulate with several to many leaves in the lower half of the stems, unless they are small and growing in full sun, in which case the two species are almost impossible to distinguish because they are both likely to be strictly rosulate ( Fig. 28 a ). Larger plants of N. rosulata retain their rosulate habit, whereas those of N. karara develop sometimes numerous stem leaves ( Fig. 28 b ). Both occur in similar sites and have nearly glabrous upper stems, which distinguishes them from the species of the N. rotundifolia complex, to which they are both closely related ( Fig. 1 b ). Nicotiana rosulata is mainly found in the Goldfields area from Leonora as far west as Dalgaranga Station just to the north-west of Mount Magnet, whereas N. karara is slightly disjunct and occurs in the Salt River and Murchison River drainages.

Selected specimens examined

WESTERN AUSTRALIA. Great Northern Highway (95), north of Jibberding , 315 m, 29°28′0″S, 117°11′56″E, 5 Aug. 2015, Chase & Christenhusz 68152 ( PERTH) ; Mungada Road to the Karara Mine, Boiada Camp , 300 m, 29°11′37″S, 116°30′35″E, 23 Aug. 2015, Chase & Christenhusz 68285 ( PERTH) ; Bowgada–Mullewa road to Wubin , 340 m, 29°20′22″S, 116°10′2″E, 23 Aug. 2015, Chase & Christenhusz 68288 ( PERTH) ; Great Northern Highway (95), ~ 5 km north of Mount Magnet, in the Granites , 465 m, 28°0′25″S, 117°51′27″E, 18 Sep. 2016, Chase & Christenhusz 16185 ( PERTH) ; Yalgoo–Paynes Find road, south-east of Yalgoo , 335 m, 28°28′52″S, 116°49′21″E, 19 Sep. 2016, Chase & Christenhusz 16193 ( PERTH) ; Yalgoo–Paynes Find road, south-east of junction with track to Thundelarra Station , 320 m, 28°51′8″S, 117°4′39″E, 19 Sep. 2016, Chase & Christenhusz 16197 ( PERTH) ; Yalgoo–Paynes Find road, north-west of Paynes Find , abundant on verges, 330 m, 29°1′21″S, 117°14′27″E, 19 Sep. 2016, Chase & Christenhusz 16199 ( PERTH) ; Great Northern Highway (95), near salt ponds north of Jibberding , 290 m, 29°50′55″S, 116°56′19 117°11′56″E, 19 Sep. 2016, Chase & Christenhusz 16203 ( PERTH) ; 1.9 km north of Galatea Bridge on Highway 1, eastern side of road, 200 m, 27°48′39″S, 114°41′25″E, 21 Sep. 2019, Chase & Christenhusz 19136 ( PERTH) ; Morawa–Yalgoo road, Barnong Station, western side of road, ~ 47 km south-west of Yalgoo , 290 m, 28°38′2″S, 116°19′1″E, 22 Sep. 2019, Chase & Christenhusz 19136 ( PERTH) .

Figures

Fig. 28. Variation in habits of Nicotiana karara. (a) Habit of Nicotiana karara, at the type locality, Mungada Road to the Karara Mine, Western Australia, Chase & Christenhusz 28280. (b) Habit of Nicotiana karara, Bowgada–Mullewa road, Western Australia, Chase & Christenhusz 28288. Note the strict rosette in this small plant in nature; the same accession has stem leaves in cultivation (Fig. 27). The plant in (b) has stem leaves in nature. Photographs by Maarten Christenhusz.

Fig. 1. Phylogenetic tree for the species of Nicotiana section Suaveolentes, based on the RADseq (nuclear) data matrix of Chase et al. (2021, 2022b), to which we have added the accessions for the new species reported in this paper. Vouchers for these added accessions are indicated under the additional specimens examined for each of the new species. All nodes for which there are no bootstrap percentages indicated are 100. (a) The basal nodes of the RADseq tree. (b) The more derived clades in the same RADseq tree as in (a).

Fig. 29. Map of distributions of Nicotiana karara (red circles), N. rosulata (purple circles) and N. erytheia (green circles) in Western Australia. Created by Maarten Christenhusz from data downloaded from the Australasian Virtual Herbarium website.