Pabstiella pseudotrifida L. Kollmann & D. R. Couto, 2014

Kollmann, Ludovic Jean Charles & Couto, Dayvid Rodrigues, 2014, Pabstiella pseudotrifida L. Kollmann & D. R. Couto (Orchidaceae), a new species from Espírito Santo, Brazil, Candollea 69 (1), pp. 21-24 : 22-24

Pabstiella pseudotrifida L. Kollmann & D. R. Couto , spec. nova ( Fig. 1 ).

Typus: BRAZIL. Edo Espírito Santo: Mimoso do Sul, Santa Luzia , ca., 7.I.2005, fl., D. R. Couto 229 (holo-: MBML) .

Pabstiella pseudotrifida is very similar to P. trifida , but can be distinguished by the subtruncate to truncate petals, and the smooth lip which is free of callosities and truncate to rounded at apex.

Plant epiphytic, 2-4 cm tall, caespitose, erect. Roots whitish, terete, flexuose, glabrous. Ramicauls 5.5-7 mm long., green, cylindrical, enclosed by tubular, acute, pale green sheaths that are paleaceous and whitish when dried. Leaves 16-28 X 3-3.5 mm, 0.8-1.6 mm thick, green, linear-elliptic, the base subpetiolate, the apex minutely 3-dentate, Inflorescence a congested, successively several-flowered raceme, 1.2-1.7 cm long, shorter than the leaves. Floral bracts ca. 1.5 mm long, translucent, pale green, tubular, acute. Flowers resupinate, glabrous. Pedicels 1.5-2 mm long. Ovary 1-1.2 mm long. Sepals yellow, translucent, with orange margins, 3-veined, carinate abaxially, the dorsal sepal 5-5.5 X 1.9-2 mm, oblong-elliptic, obtuse, the laterals sepal 4-4.1 X 1.4-1.5 mm, connate to above the middle into a oblong synsepal with acute apices, forming a small mentum below the tip of the column-foot. Petals 2.6-3.3 X 1.2-1.4 mm, spathulate, curved, 3-veined, translucent yellow with orange veins, slightly carinate abaxially, subtruncate to truncate. Lip 2.5-2.6 X 0.91 mm, orange, slightly purplish-lilac at base, green at the attachment with the column-foot, 3-lobed, unguiculate, 3-veined, the midvein longer than the laterals, smooth, free of callosities, the lateral lobes more or less below the middle, erect, broadly rounded, the apical lobe truncate to rounded. Column ca. 2.5 mm long, greenish, winged above the middle, white and 3-dentate at apex, the teeth straight and acute; column-foot 1.3-1.8 mm long with two callosities at base the apex papillose. Anther ca. 0.7 mm long, yellowishwhite; pollinia two, yellow. Capsule unknown.

Etymology. – The specific epithet refers to its similarity to P. trifida (Lindl.) Luer.

Habitat, distribution. – This species is apparently endemic to the Atlantic forest of southern Espírito Santo, growing as an epiphyte in dense rainforest remnants, from 800 to 1600 m altitude. It is partially protected in the mountain forests of the Caparaó National Park ( Fig. 2 ).

Conservation status. – Due to the apparently endemic distribution of P. pseudotrifida , and on the basis of the extension of its occurrence in the State of Espírito Santo, which is estimated to be less than 500 km 2, it seems appropriate to include this new species in the “Endangered” (EN) category (B2a(iii)), according to the IUCN (2001).

Taxonomical notes. – Pabstiella pseudotrifida is most similar to P. trifida , from which it may be distinguished by its petal and lip morphology. In P. pseudotrifida the petals are subtruncate or truncate, and the lip is smooth, free of callosities, truncate or rounded at apex, with side lobes above the middle. In P. trifida , the petals are obtuse or acute, the lip is papillose or verrucose, the side lobes are near or below the middle, and the disc is shallowly channelled between a pair of verrucose, intramural calli.

Paratypi. – BRAZIL. Edo Espírito Santo: Divino de São Lourenço, Patrimônio da Penha, Dense Ombrofilous Forest, border of Caparaó Nacional Park , ca. 1100 m, 20.III.2009, fl., D. R. Couto 1433 ( VIES); Ibitirama, Caparaó Nacional Park , Rio Santa Marta valley , ca. 1600 m, Altimontane Dense Ombrophilous Forest, 22.I.2013, fl., H. M. Dias, A. E. Silva & al. 827 ( VIES); Castelo, Forno Grande , 1000 m, 10.V.2006, fl., A. Gussão s.n.; s.loc., fl. cult. 21.VII.2008, L. Kollmann & al. 11495, ( MBML) .

Figures

Fig. 1. – Pabstiella pseudotriFida L. Kollmann & D. R. Couto. A. Habit; B. Flower (side view); C. Dorsal sepal; D. Lateral sepals; E-F. Petals; G. Lip (spread); H. Lip (lateral view); I. Column (apical portion spread and from below); J. Column and ovary (lateral view); K. Anther (1. ventral face, 2. dorsal face). [D. R. Couto 229, MBML] [Drawn by L. Kollmann]

Fig. 2. – Distribution of Pabstiella pseudotriFida L. Kollmann & D. R. Couto (triangles) in Southern Espírito Santo, Brazil.