Tillandsia uruguayensis
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Tillandsia uruguayensis

Derek Butcher 27/03/18. "Hot off the press. If you have a T. lorentziana and it can be traced to Uruguay then the enclosed is a compulsory read! I feel sure that the Europeans like Lotte Hromadnik has Uruguay contacts. You never know."

Tillandsia uruguayensis Rossado, sp. nov. (Figs. 1-2) Phytotaxa 345 (2): 133-142. 2018
Tillandsia uruguayensis is morphologically very close to T. lorentziana but differs from the latter by its longer basal floral bracts (26-45(- 51) mm vs. l9-28(-32) mm long), sepals from the basal flowers reaching less than ¾ of the length of its respective floral bract (vs. more than ¾ , spatulate petals (vs. lingulate), and straight filaments (vs. plicate).
Type- URUGUAY. Rivera: Cerro Batovi Dorado, paredones de arenisca endurecida, [31°4'19"S, 55°25'42"W], 30 August 2001 (f1.). C, Brussa s.n. (holotype MVFA 29683!).

Plant epilithic, short to long caulescent, branching strongly at the base and forming very dense clumps up to 60 cm in diameter. Roots up to 2.5 mm in diameter, present all along the stern, branched.
Stems usually short but sometimes long (to 1 m long), then pendant for most of its length and apically ascending, old parts covered by remaining dry sheaths.
Leaves spirally arranged, 9-19.5 cm long, 6 to 15 in number and clustered apically when the stem is developed;
Sheaths 1.6-4 x 1.5-3.1 cm, enfolding the stem, gradually merging into blades, fleshy and with membranaceous margins at the basal portion, white and greenish towards the blades, densely lepidote abaxially except for the glabrous very base, mostly glabrous adaxially except for the densely lepidote distal portion, trichomes appressed becoming tomentose towards the blades, margins with protruded larger trichomes at the distal portion;
blades 5.5-16.5 x 0.7-1.8 cm, erect to divergent (seldom the older ones spreading), sometimes turning secund, very narrowly triangular, channeled except for the flat apex, fleshy, cinereous, densely tomentose-lepidote on both sides, margins with protruded larger trichomes at the base, trichomes asymmetric, apex narrowly acute.
Inflorescences simple, 9-37 cm long (including the peduncle).
peduncles elongate. slightly shorter to exceeding the leaves, wholly covered by bracts, (4.4-5.5-22(-27.5) cm long. 1.8-3 mm in diameter, suberect to reflexed but mostly horizontal, straight or occasionally slightly curved, terete, greenish, glabrous;
peduncle bracts 6-9(-13) in number, erect. clasping the peduncle, densely imbricate, at least twice as long as the internodes, the basal ones leaf-like, very densely lepidote, the upper ones bladeless, gradually resembling the floral bracts, (2.6-)3.1-5(-5.6) x 0.8-1.4 cm, narrowly elliptic-triangular to narrowly elliptic, chartaceous, grayish-green or grayish-red, apex acute to obtuse, glabrous adaxially, sparsely lepidote to densely lepidote abaxially except for the usually glabrous base;
fertile part of the inflorescence distichously and densely (2-)4-11(-16)-flowered, 4-11(-15) cm long, 0.7-2 cm wide, straight, strongly complanate, narrowly elliptic, apex acute with one or few sterile bracts;
rachis totally or partially hidden by the floral bracts, (1.3-)2-8.5(-12.7) cm long, stout, slight to distinctly flexuous, compressed excavate next the flower, green, glabrous;
floral bracts conspicuous, gradually reducing in size towards the apex, densely imbricate, 3-5 times longer than the internodes, suberect to erect, clasping the basal half of the flower, narrowly elliptic to narrowly triangular, ecarinate, prominently nerved, light green, yellowish-green, reddish or light pink, margins thin and nerveless, apex acute to obtuse, the basal floral bracts 26-45(-51) x 9.8-14 mm, exceeding the sepals by 9-22 mm, densely lepidote to glabrescent abaxially or less frequently glabrous, trichomes generally denser or concentrated towards the apex only, the upper floral bracts shorter, usually glabrous.
Flowers 36-57 mm long, suberect to erect sessile, odorless; receptacle totally hidden by the floral bract, inconspicuous but stout, 0.6-3.2 mm long, green;
sepals hidden by the floral bracts, 15-27 x 3.5-7.3 mm, erect, nearly straight, evenly very short connate at the base for less than 1 mm to free, narrowly elliptic to narrowly elliptic-ovate, sometimes narrowly elliptic-oblong, submembranaceous, prominently nerved, light pink to greenish, glabrous, margin thin and nerveless, apex acute, the abaxial sepal ecarinate, the adaxial sepals strongly carinate and usually longer and wider than the abaxial one;
petals 36-57 mm long, free, spatulate, membranaceous, white; claws 3-4 mm wide, erect; limbs 5.7-10.5 mm wide, divergent to spreading, sometimes recurved towards the apex, elliptic, margins softly crenate, seldom entire, apex rounded or seldom obtuse;
stamens 30-45 mm long, all equal in length, included but visible, equaling the petal claw, filaments 24-37 mm long, flat flaccid, sublinear, gradually tapering distally, straight (not plicate), translucent; anthers 5-9 mm long, linear, subbasifixed, apically with a short connective extension; pistil 32-52 mm long slightly exerted, exceeding the stamens;
ovary 3.5-7 x 1.5-3.6 mm, ovoid, tapering into the style, light green; style 25-45 mm long, ca. 6-8 times as long as the ovary, white;
stigmas simple-patent, whitish, lobes 1.3-2.8 mm long, linear, spreading slightly recurved, densely papillate.
Capsules 19-30 x 4-6 mm, totally or mostly covered by the sepals and not exceeding its respective floral bract, narrowly ellipsoid, erect apex acute and up to 3.5 mm beaked.

Etymology:-The specific epithet refers to Uruguay, the country where the type specimen was collected.

Distribution and habitat - Tillandsia uruguayensis is only known from northern Uruguay, in northern and northwestern Rivera and northern Tacuarembo (Fig. 3), where it grows epilithical on vertical rocky surfaces at elevations of 150-300 m. The habitat includes rocky cliffs alongside Lunarejo and Laureles rivers and their tributaries, the rocky walls of flat hills, and the rocky pillars of Tacuarembo (Fig. 2A-B). This xeromorphic species grows fully sun exposed, usually forming almost exclusive communities but sometimes associated with Dyckia sp. (Bromeliaceae) and several cacti species. Furthermore, T. uruguayensis occasionally grows as an epiphyte on trees close to the rocky surfaces where it is more abundant.
Additional sampling may further extend the distribution of Tillandsia uruguayensis, as there are other areas with suitable habitat for this species in northern Uruguay and southwestem Rio Grande do Sul, Brazil. However, despite having carried out an exhaustive search in several herbaria collections (mainly Brazilian herbaria cited above), we did not find any specimen supporting a wider distribution.

Ecology:-Tillandsia uruguayensis is a xeromorphic species due to its densely lepidote and gray-like leaf blades with conspicuous water storing tissue (Barfuss et al. 2016). Furthermore, this species is categorized as an atmospheric Tillandsia as it is a non-tank plant that depends on almost exclusively absorptive leaf trichomes for water and nutrient uptake (Benzing 2000).

Phenology:-Tillandsia uruguayensis flowers from late August to early November. Plants with unopened capsules were observed from October to April and seed dispersal from February to April. The flowering period lasts for 20 to 30 days in well-developed inflorescences. Generally, only one to two flowers are open at the same time per inflorescence. Each flower remains open for three to seven days.

Conservation assessment:- Tillandsia uruguayensis was categorized in the AOO analysis as Endangered (EN). This species is only known from about 10 scattered populations always associated with rocky walls or pillar formations of rare occurrence in the country. The rocky cliffs at the sources of Lunarejo and Laureles rivers, where some populations of this species are located, are well-preserved habitats mostly because of its difficult accessibility (Fig. 2A-B). Unfortunately the habitat at the flat hills of Rivera and the rocky pillars of Taouarembo are threatened by Pinus plantations. Tillandsia uruguayensis has some of its populations protected as they occur in the conservation area 'Paisaje protegido Valle del Lunarejo". Nevertheless, conservation of the different localities where this species occurs is important not only due to its restricted distribution, but also because each population is unique in several morphological features (e.g. plant size, number of flowers per inflorescence, floral bracts color, size of flower and its parts, among others).

Taxonomic observations: Tillandsia uruguayensis was collected for the first time in 1900 by Jose Arechavaleta in Tacuarembo (Uruguay) without specifying the exact locality. This species was not collected again until 1984 and ever since then, several specimens have been herborized and identified only to generic level or as Tillandsia arequitae or T. xiphioides (Brito & Llano 2008) Fig. 4A-D). The last two species occur in Uruguay and despite being morphologically similar to T. uruguayensis, they both show clear differences with it. Tillandsia uruguayensis can be distinguished from T. arequitae by its erect to divergent and channeled leafblades (vs. spreading to reflexed and flat at the base), odourless flowers (vs. fragrant), narrower petals limb (up to 10.5 mm vs. 11.5-17 mm wide), and sepals of the basal flowers reaching less than ¾ of its respective floral bract (vs. ca. ¾ or higher), among others characteristics (Table 1). On the other hand, T. uruguayensis can be distinguished from T. xiphioides by its odorless flowers (vs. strongly fragrant), shorter sepals (1.5-2.7 cm vs. 3.2-5.2 cm long), smaller petals (less than 6 cm vs. at least 8.5 cm long), and narrower petals limbs (up to 10.5 mm vs. at least l7 mm wide) (Table l).
Specimens of Tillandsia lorentziana Grisebach (1874: 271) with simple inflorescenses are the ones that morphologically show the greatest likeness to T. uruguayensis (Fig. 4E-F)- Tillandsia lorentziana is a widely distributed species that occurs in Argentina, Brazil, Bolivia, and Paraguay and although it has not yet been registered for Uruguay it has been collected in Rio Grande do Sul (Brazil) in an area very close to the border with Uruguay.
Tillandsia uruguayensis differs from T. lorentziana by its channeled leafblades (vs. flat at the base), sepals of the basal flowers reaching less than ¾ of its respective floral bract (vs. more than ¾ ), spatulate petals (vs. lingulate), and straight filaments (vs. plicate) (Table 1).

Additionally, Tillandsia uruguayensis shows morphological similarities with Tillandsia afonsoana Strehl (2000: 23), T. barfussii, W. Till (2009: 36), T. cardenasii L. B. Smith (1935: 154), and T. chiletensis Rauh (1984: 5). Tillandsia afonsoana is an endemic species from Rio Grande do Sul (Brazil) morphologically similar to T. lorentziana. Tillandsia uruguayensis can be easily distinguished from T. afonsoana because its floral bracts exceed its respective sepals by at least 9 mm (vs. equal in length to the sepals or exceed them by at most 6 mm), it has straight filaments (vs. plicate), and floral bracts 9.8-14 mm wide (vs. 8.0-10 mm). Likewise, Tillandsia uruguayensis differs from Tillandsia cardenasii, an endemic species from Bolivia, by its longer basal floral bracts (26-51 mm vs at most 27 mm long), sepals from the basal flowers reaching less than ¾ of the length of its respective floral bract (vs. barely shorter), petals spatulate, white, 5.7-10.5 mm wide (vs. lingulate, lilac, 2-4 mm wide), and straight filaments (vs. plicate). Tillandsia barfussii and T. chiletensis show morphological similarities wlth T. uruguayensis, especially regarding reproductive structures. Tillandsia uruguayensis can be distinguished from both species by its longer floral bracts (26-51mm) vs. T barfussii: 19-21 mm, T. chiletensis: (ca. 25 mm long), sepals much shorter to its respective floral bracts (vs. equal or subequal), and outer leafblades channeled (vs. flat at least at the base). In addition, T. uruguayensis has densely lepidote leaf sheaths (vs. T. chiletensis: glabrous sheaths), floral bracts 9.8-14 mm wide {vs. T. chiletensis: ca. 6 mm), and straight filaments {vs. T. barfussii: plicate).
It should be noted that Tillandsia lorentziana f . simplex Kuntze (1898: 304), currently considered a synonym of T. lorentziana, was differentiated in the original publication from the typical form by the presence of simple inflorescences instead of compound ones. Given that T. uruguayensis is morphologically similar to plants of T. lorentziana with simple inflorescences, we analyzed the type material and the protologue of T. lorentziana f. simplex and concluded that this form has no other differences with the typical form except for the inflorescence type. Thus, we reject the possibility that material here recognized under T. uruguayensis correspond to T. lorentziana f . simplex.

Additional specimens examined (Paratypes):-URUGUAY. See image.

Introduction Tillandsia Linnaeus (l753: 286) is the largest and most widely distributed genus of the family Bromeliaceae Jussieu. It comprises 702 species (Gouda et al. continuously updated) of mainly epiphytic and epilithic herbs, distributed from southern United States to central Argentina and central Chile (Smith & Downs 1977, Zizka et al. 2009, Barfuss et al. 2016, IBODA continuously updated). Tillandsia is included in the subfamily Tillandsioideae Burnett due to the presence of dry dehiscent capsular fruits and seeds with plumose appendages (Smith & Downs 1977, Givnish et al. 2011, Barfuss et al. 2016).
Currently, Tillandsia is organized into seven subgenera and several species complexes (Barfuss el al. 2016). Tillandsia subg. Aerobia Mez (1896: 812) was recently resurrected and re-circumscribed by Barfuss et al. (2016), and is represented by 50 epilithic or epiphytic xeromorphic species, morphologically characterized by the absence of a central tank, flowers distichously arranged, petals free and without appendages, and a simple-erect or simple-patent stigma type (Barfuss et al. 2016).
In Uruguay, Tillandsia is distributed throughout the Country and includes 15 native species, most of them epiphytic. Tillandsia subg. Aerobia is represented by three species that in Uruguay grow as epilithic: T. xiphioides Ker Gawler (1816: t. 105), the endemic T. arequitae (Andre 1893: 156) Andre ex Mez (1896: 814) and the new species described in this paper.
In this work, we describe and illustrate the new species, provide information on its geographical distribution, habitat, and phenology, and discuss the differences between the new species and morphologically related ones.

Material and methods
As part of the taxonomic revision of the genus Tillandsias in Uruguay currently underway, we identified a new species based on data from herbaria field collected specimens and observation of plants in cultivation. We analyzed herbarium material of both the new taxon and the morphologically similar species deposited in the herbaria BA, BAB, CTES, HAS, HDCF, ICN, LP, MVFQ, MVFQ, MVJB, MVIU, PACA, PEL, SI (acronyms according Thiers, continuously updated). In addition, for morphologically similar species we consulted type material, protologues and, when available, we observed cultivated specimens.
Fieldwork was conducted in 2014 and 2015 with the main purpose of obtaining information on habitat, and morphological features that are usually lost in dried specimens, such as architecture, color, texture of plant's parts, and flower odor as well. The aim was also to document morphological variation between populations and verify the taxonomical value of several informative features. Our collection included herbarium specimens, inflorescences and flowers in 70% ethanol, and plants for cultivation. Dried specimens were deposited in MVFA and SI.
We photographed plants in their natural habitat as well as in cultivation. The illustration was prepared on the basis of live material and from flower's parts preserved in 70% ethanol. Phenology was determined from herbarium specimens and from observations made on cultivated plants and wild populations. Furthermore, cultivated plants were manually cross-pollinated in order to obtain fruits and assess the timing of fruit dehiscence. These fruits were also used for morphological description.
Geographic distribution was obtained from herbarium and recently collected specimens. In case of absence of geographic coordinates in herbarium specimens, these were estimated from label information and are shown between brackets (see “Additional specimens examined" list).
The conservation status of the species was assessed under IUCN guidelines and criteria (IUCN 2017) on the basis of georeferenced data. We applied the criterion of Geographic range through the assessment of Area of occupancy (AOO) (IUCN 2012) estimated using the software GeoCAT- Geospatial Conservation Assessment Tool (Bachman et al. 2011) with a cell width of 2 km. Given that Tillandsia uruguayensis shows a discontinuous geographic distribution, we consider the AOO a good predictor for its real geographic distribution.
General morphological terminology followed Simpson (2006), and specific morphological terminology for Bromeliaceae is according to Smith & Downs (1977), with adaptations following Scharf & Gouda (2008) and Barfuss et al. (2016). Additionally, we defined the character "sepal apparent length" (SAL) as the distance between the base of a floral bract and the apex of its respective sepals (Fig. lH). This character proved to be useful to species differentiation, besides being convenient as a non-destructive method in handling of herbarium specimens.

Updated 08/07/18