Senecio espiritosantensis A.Teles, 2018

Teles, Aristônio Magalhães, 2018, Senecio espiritosantensis (Compositae: Senecioneae), a new species from Espírito Santo, Brazil, Phytotaxa 334 (3), pp. 297-300 : 297-299

Senecio espiritosantensis A.Teles , sp. nov. ( Fig. 1 )

Differs from Senecio hatschbachii Cabrera (1974: 1) in its radiate capitula and 5 involucral bracts (versus discoid capitula and 13 involucral bracts), and also differs from S. macrotis Baker (1884: 308) in its serrate leaf margins and radiate capitula (versus lyrate-pinatissect leaf margins and discoid capitula).

Type:— BRAZIL. Espírito Santo: Águia Branca, Santa Luzía, Pedra do Ciro, 175–420 m, 18°58 ′ 39.5 ″ S 40°39 ′ 52.9 ″ W, 03 October 2007, H. Q. Boudet Fernandes, V. Demuner, T. A. Cruz & R. R. Vervloet 3457 (holotype BHCB! [ BHCB 003479], isotype: MBML!).

Giant herbs 1.5 − 2 m tall, perennials, single-stemmed. Stem 6 − 8 mm in diam., striate, pithy, sericeous. Leaves petiolate, petiole 2 − 5 cm long, alternate, internodes 1 − 7 cm long, blades ovate, 4 − 14 cm long, 1.7 − 5.5 cm wide, apex attenuate, base cordate, margins serrate, teeth apex brownish, blade penninervate, discolorous, adaxial surface green-gray, sericeous, abaxial surface brownish yellow, densely arachnoid, eglandular. Capitulescence terminal, paniculiform, condensed. Capitula heterogamous, radiate, pedunculate; peduncles 1 − 5 mm long, densely arachnoid, bracteolate; bracteoles lanceolate, 2 − 6 mm long, ca. 0.5 mm wide, arachnoid; involucre cup-shaped, 5 − 6 mm long, 3 − 4 mm diam.; involucral bracts 5, margins scarious, entire, glabrous; receptacle flat, alveolate. Ray florets pistillate, 3 − 4 per capitulum; corollas liguliform, yellow, tube ca. 3 mm long, limb ca. 4 mm long, ca. 1 mm wide, 3-lobed; style ca. 6 mm long, branches curved, ca. 1.0 mm long; cypsela ca. 1.5 mm long, turbinate, glabrous, 6-ribbed; pappus 3 − 4 mm long, bristles barbellate, whitish, persistent. Disc florets bisexual, 4 − 6 per capitulum; corollas tubular, yellow, ca. 6 mm long,, ca. 1.7 mm diam., 5-lobed, lobes ca. 1 mm long, tube and lobes glabrous; filaments with anther collar balusterform, anthers ca. 3 mm long, inserted, base sagittate, connective with an oblong appendage ca. 0.5 mm long; style ca. 7 mm long, base cylindrical and glabrous, branches diverging, ca. 1 mm long, apex obtuse, with a short, sterile pappilose appendage, crowned by simple, divergent trichomes; cypsela ca. 1.5 mm long, turbinate, 6-ribbed, glabrous, carpopodium inconspicuous; pappus 3 − 5 mm long, bristles barbellate, whitish, persistent. Figure 1 .

Additional specimen examined:— BRAZIL. Espírito Santo: Águia Branca, Pedra da Bandeira, Santa Luzía, prop. Ciro Ferreira, 170 − 600 m, 18°58 ′ 40 ″ S 40°39 ′ 56 ″ W, 26 July 2006, L. F. S. Magnago, V. Demuner, T. Cruz & Elias Bausen 1112 ( BHCB! [ BHCB 003478], MBML!).

Distribution and Ecology:— This new species is so far known only from the Águia Branca municipality, Espírito Santo State, Brazil. In the few known populations, the species was found growing as a rupicolous plant on sun-exposed granitic rocks on the summit of inselbergs from 170 − 600 m elevation. This area is one of the last remnants of Atlantic Forest in Espírito Santo State.

Conservation Status:— Senecio espiritosantensis according to IUCN Red list categories and criteria ( IUCN 2017) is considered Critically Endangered (CR subcriteria B1 and 2 – extent of occurrence estimated to be less than 100 km 2, area of occupancy estimated to be less than 10 km 2) as it grows in a highly specialized habitat and is known from a few populations, found in an area with difficult access.

Phenology:— Specimens were collected with florets and fruits in July and October.

Etymolgy:— The specific epithet refers to the type locality of the species, the Espírito Santo State from where the species is supposedly endemic.

Discussion:— Senecio espiritosantensis belongs to S. sect. Cacaliastrum by its robust habit, big leaves, which are conspicuously petiolate with petioles usually winged, as well as capitula discoid or radiate.This new species is morphologically similar to S. hatschbachii and S. macrotis , the differences of which are mentioned above and below in a key to the species of S. sect. Cacaliastrum.

Figures

FIGURE 1. Senecio espiritosantensis. A. Habit. B. Capitulum. C. Ray floret. D. Disc floret. E. Stamens. F. Style of the disc florets. (All illustrations made from the holotype. Drawings by Cristiano Gualberto dos Santos).