Ivania juncalensis Al-Shehbaz (2010: 345)

Cádiz-Véliz, Arón, Román, Nicolás Marín, Urbina-Casanova, Rafael, Berguecio, Nicolás García, Palma-Villalobos, Bárbara & Sapaj-Aguilera, Guillermo, 2022, Rediscovery of Ivania juncalensis Al-Shehbaz (Thelypodieae; Brassicaceae), an endemic and threatened species from the Andes of Central Chile, Phytotaxa 558 (3), pp. 276-282 : 277-280

Ivania juncalensis Al-Shehbaz (2010: 345) . ( Fig. 1 , 3 )

Type: — CHILE. Región de Valparaíso, Provincia de Los Andes, Valle del Río Juncal , 2500 m.a.s.l., 15 December 1976, Otto Zöllner 9165 (Holotype NA 5434) .

Description (Modified from Al-Shehbaz 2010): —Herbs, perennial, glabrous throughout. Caudex woody, densely covered with petiolar remains of previous years, several branches terminated in rosettes. Stems 8‒30 cm, erect, leafy. Basal leaves rosulate, not fleshy, more or less leathery; petiole 3.5‒9 cm; blade 2‒8 × 0.7‒3.5 (5) cm, oblong to lanceolate, pinnatifid to pinnatisect, base cuneate. Cauline leaves 1‒5 × 0.1‒1 cm, petiolate, linear-oblanceolate, entire to pinnatifid. Raceme elongated in fruit 5–12 cm long, branched, with cauline leaves up to the first flower of each branch; pedicels 1‒2 cm, divaricate-ascending. Sepals 2.5‒3 mm, ovate; petals 6‒7.5 × 2.5‒3 mm, white, spatulate, claw 3‒3.5 mm long; filaments 3‒3.5 mm long; anthers ca. 1 mm long, oblong; gynophore absent (~ 0.5 mm long in fruit); style 0.2‒0.5 mm long; stigma capitate, strongly 2‒lobed. Fruit siliqua, 2.5‒5 × 0.1‒0.2 cm, linear, slightly curved, terete, each valve with 2-3 longitudinal veins, replum terete, septum complete and veinless; seeds 2‒3 × 1 mm, uniseriate on each valve, numerous, pyramidal, acuminate, brown.

Distribution and habitat: — Ivania juncalensis is endemic to the Andes of the Región de Valparaíso (Al-Shehbaz 2010, Rodríguez et al. 2018) and, until now, it is only known from the locality reported in this article. It is located in the private protected area Parque Andino Juncal, in the Río Juncal valley, Región de Valparaíso, Chile ( Fig. 2 ). It is found between 2500 and 2900 m.a.s.l. in the “Mediterranean Andean dwarf scrub of Chuquiraga oppositifolia D. Don (1832: 392) and Nardophyllum lanatum (Meyen) Cabrera (1954: 63) ” vegetation type, which is found on high hillsides of the Andes between the provinces of Choapa and Colchagua ( Luebert & Pliscoff 2017). However, I. juncalensis grows exclusively in rock crevices ( Fig. 3 ), generally oriented towards the southwest, where it was observed along with Bowlesia tropaeolifolia Gillies & Hook. (1830: 325) , Cystopteris apiiformis Gand (1913: 28) , and Valeriana stricta Clos ([in Gay] 1848: 235). Based on field observations, we estimate its population size is less than 250 mature individuals.

Studied material: — CHILE. Valparaíso: Los Andes Province, Juncal River Valley, Parque Andino Juncal , La Yesera sector, on a rocky slope with SW exposure, 32°54’14”S; 70°05’40”W, 2870 m.a.s.l., November 29th, 2021, A. Cádiz-Véliz & N. Marín 802 (JBN!, EIF!, VALPL!, SGO!, CONC!); February 14th, 2022, A. Cádiz-Véliz & B. PalmaVillalobos 961 (EIF) .

Ecology: —During the visits we did not observe pollinators, but we presume the species is pollinated by bees and/or flies due to the presence of nectaries and its floral morphology. After fruits dehisce, seeds are primarily gravity dispersed and helped by wind and water. It is likely that most seeds fall near the mother plant, which could partially explain its extremely restricted distribution.

Phenology: —Flowers from early November to late December, and fruits from mid-December to mid-February.

Conservation status: —The conservation status of I. juncalensis had not been assessed until now, although Warwick et al. (2011) mentioned it should be listed as “highly endangered”. Here we propose to list it as Critically Endangered (CR) B1+B2a (i,ii,iii) following the IUCN (2012) criteria, as its extent of occurrence (EOO) is <100 km 2, its area of occupancy (AOO) is <10 km 2, it is known from only one locality, and its distribution and habitat suitability are expected to decrease under the effects of climate change (Luebert & Pliscoff 2012, Pliscoff et al. 2012). Some individuals showed signs of herbivory and we observed exotic lagomorphs in its habitat. Moreover, in the Andes of the Valparaíso Region there is goat and cattle farming, and multiple mining projects, such as the Nutrex mining project located less than 3 km away from the collection locality ( Fig. 2 ).

Taxonomic and phylogenetic considerations: The type species of Ivania was originally described by Johnston (1929) in Cardamine L. (1753: 654) and later transferred to Ivania ( Schulz 1933) . However, morphological differences to distinguish both genera have not been proposed. The genus Cardamine (Cardamineae tribe) is characterized by the presence of siliquae linear to subulate, latiseptate or rarely subterete with valves dehiscing elastically, and flattened replum, while Ivania (Thelypodieae) has siliquae linear and terete, with valves not dehiscing elastically, and terete replum (Appel & Al-Shehbaz 2003). Nevertheless, phylogenetic analyses using ITS clearly placed both Ivania species within the Thelypodieae tribe, along with other South American genera such as Chilocardamum O.E. Schulz (1924: 179) , Pringlea W.Anderson ex Hook. f (1845: 238), and Polypsecadium O.E. Schulz (1924: 176) , although the phylogenetic resolution within this tribe is very poor ( Warwick et al. 2011).

Even though the monophyly of Ivania was shown by Warwick et al. (2011), it is difficult to diagnose this genus considering several outstanding morphological differences between both species (Al-Shehbaz, 2010). For example, Ivania cremnophila has an evident gynophore of 2–4 mm long, while it is absent to only 0.5 mm long in I. juncalensis (absent according to Al-Shehbaz (2010)). Before the description of I. juncalensis , the presence of a gynophore longer than 2 mm was used in the generic key of Appel & Al-Shehbaz (2003) to separate Ivania from other similar genera; therefore, a clear morphological distinction of Ivania in relation to other genera in Brassicaceae is lacking. However, Ivania is characterized by entirely glabrous plants, while most species of related genera have simple and/or forked hairs. The presence of longitudinal veins on the fruit valves of Ivania juncalensis is a potential synapomorphy shared with other genera in Thelypodieae , such as Mostacillastrum and Stenodraba O.E. Schulz (1924: 186) .

Figures

FIGURE 1. Ivania juncalensis. (A) Habit; flower (B) top view, (C) lateral view; (D) basal leaf; (E) fruit; (F) seed; (G) detail of an inflorescence with flowers, immature fruits, and cauline leaves.

FIGURE 2. Location of Ivania juncalensis in the Parque Andino Juncal, Juncal valley, Los Andes Province, Chile.

FIGURE 3. Ivania juncalensis habitat. (A, C) Plants growing among the rocks; (B) detail of the flowers and (D) the fruits; (E) multiple individuals growing in crevices (red arrows); (F) rocky wall with scarce vegetation and I. juncalensis individuals (red arrows).