Pleroma kollmanniana F.S.Mey. & R.Goldenb., 2016

Meyer, Fabrício Schmitz, Goldenberg, Renato & Kollmann, Ludovic J. C., 2016, Three new species of Pleroma (Melastomataceae) from Inselbergs of Espírito Santo, Brazil, Phytotaxa 282 (3), pp. 197-210 : 202-205

2. Pleroma kollmanniana F.S.Mey. & R.Goldenb. sp. nov. ( Figures 4–5 )

Diagnosis:— Pleroma kollmanniana differs from Tibouchina heteromalla by the strongly winged branches (the wings 3.4–5.5 mm long on old branches vs. 0.9–1.3 mm in T. heteromalla ), bigger leaves (15.5–20.5 × 8.8–12 cm vs. 6.5–11 × 3.5–7.5 cm in T. heteromalla ), and shorter petioles (1.7–2.5 mm vs. 17–28 mm in T. heteromalla ).

Type:— BRAZIL. Espírito Santo: Santa Teresa, “Pedra da Onça” (cultivated at Santa Teresa, in the “ Museu de Biologia Mello Leitão ”), 13 April 2016, (fl., fr.), F. S. Meyer & L. Kollmann 2219 (holotype: UPCB!; Isotypes: MBM!, MBML!, NY!) .

Shrub 0.7–3 m tall. Branches quadrangular, strongly winged, younger branches with wings 1.1–2.7 mm long, older ones with 3.4–5.5 mm and glabrescent, indumentum with two layers, the first moderately strigose, the trichomes 0.3–1 mm long, usually non glandular, but seldom glandular, appressed, narrow at the base, the second layer sparsely setulose, the trichomes 1.5–2.2 mm long, non glandular, curved to erect, slightly enlarged at the base. Leaves opposite; petioles 1.7–2.5 mm long; blades 15.5–20.5 × 8.8–12 cm, ovate or ovate-elliptic, concolorous, base slightly cordate, apex acute or obtuse, chartaceous, main nerves 7, acrodromous, the marginals confluent (meeting the secondaries at the leaf base before joining the midrib), main nerves very prominent, transversals and reticulation prominent on the abaxial surface; adaxial surface moderately to densely sericeous, trichomes 2–3.3 mm long, non glandular, appressed, the base slightly bullate, immersed and with a 3–4(–5)-forked base, abaxial surface moderately setose on the primary veins, trichomes 1.7–3.3 mm long, non glandular, curved, slightly enlarged at the base, moderately to densely villose on the surface, secondary, tertiary and quaternary veins, trichomes 0.2–0.5 mm long, non glandular, coiled, narrow at the base. Thyrsoid 65–80 × 28–32 cm, axis rounded to subterete, moderately setulose, trichomes 0.2–0.9 mm long, non glandular, appressed, narrow at the base; bracts caducous, leafy, petioles 1.3–1.9 mm, blade 7.1–9.8 × 2–4.6 mm, elliptic, indumentum the same as on the leaves; bracteoles early caducous, 2.1–3.4 × 1.3–2 mm, ovate, apex acute, margins entire, ciliate, abaxial surface moderately strigose-sericeous, adaxial surface glabrous. Flowers 5-merous, on pedicels 1.1–1.4 mm long; hypanthium 5.5–5.9 × 2.5–2.8 mm, oblong, smooth (not costate), densely sericeous, the trichomes 0.7–1 mm long, non glandular, dendritic with short arms, appressed, narrow at the base; sepals 3.2–3.5 × 1.9–2 mm, triangular, margins ciliolate, apex obtuse or apiculate, with the same trichomes as the hypanthium; petals purple with a white base, 15.3–19.6 × 14–15.3 mm, obovate, apex emarginate, frequently asymmetric; stamens 10, slightly dimorphic, antesepalous with filaments white, 4–4.7 mm long, sparsely to moderately setulose on the base, trichomes 0.1–0.4 mm long, glandular, erect, narrow at the base, connective white, 1–1.3 mm, prolonged below the thecae, sparsely setulose, trichomes 0.1–0.3 mm long, glandular, erect, narrow at the base, ventral appendages 2, ca. 0.2 mm long, glabrous, thecae white or light purple, 4.7–5.2 mm long, antepetalous stamens with filaments white, 4–4.2 mm long, sparsely to moderately setulose on the base, trichomes 0.1–0.3 mm long, glandular, erect, narrow at the base, connective white, 0.5–0.7 mm, prolonged below the thecae, sparsely setulose, trichomes 0.1–0.2 mm long, glandular, erect, narrow at the base, ventral appendages 2, ca. 0.1 mm long, glabrous, thecae white, 3.1–3.4 mm long; ovary 4.2–4.6 × 2.7–3.2 mm, 5-locular, apex densely setulose, trichomes 0.4–0.7 mm, non glandular, erect, narrow at the base, style white, 4.4–4.8 mm long, apex curved, moderately setulose on its lower half, trichomes 0.2–0.6 mm, non glandular, erect, narrow at the base. Capsules 8.9–9.8 × 4.5–5.5 mm, slightly costate, not lacerated when mature.

Paratypes:— BRAZIL. Espírito Santo: Santa Teresa, Alto Rio Perdido, 19 August 2010, (fl., fr.), L. Kollmann & R. M. Pizziolo 11988 ( MBML!, G!) ; 1 November 2010, (fl.), L. Kollmann & R. L. Kollmann 12070 ( MBML!, VIES!) ; cultived at “ Museu de Biologia Mello Leitão ”, 16 October 1990, (fl.), H. Q. Boudet Fernandes 2309 (or 3023) ( MBML!, UPCB!) ; Pedra Alegre, 13 April 1996, (fl., fr.), H. Q. Boudet Fernandes et al. 3164 ( MBML!, RB!, UPCB!) ; Pedra da Onça , 11 September 2005, (fl., fr.), A. P. Fontana et al. 1685 ( MBML!, K!) ; 1 January 2006, (fl., fr.), R. C. Britto et al. 66 ( MBML!, P!) ; 26 July 2006, (fr.), A. M. Assis et al. 894 ( MBML!, UPCB!) ; 16 January 2013, (fl.), L. Kollmann et al. 12573 ( MBML!, HUEFS!) ; Toma Vento , 14 August 2001, (fl.), L. Kollmann & E. Bausen 4335 ( MBML!) ; 26 August 2014, (fl., fr.), L. Kollmann & D. Couto 12965 ( MBML!). São Roque do Canaã, Alto Misterioso , 19 March 2004, (fl.), C. N. Fraga et al. 1143 ( FLOR!, MBML!, RB!) .

Distribuition and habitat:— Pleroma kollmanniana occurs only in Espírito Santo, between 800– 1.200 m, in vegetation associated to rocky outcrops intermingled with high montane rain forest (“Floresta Ombrófila Densa Altomontana”) and high montane seasonal forest (“Floresta Estacional Semidecidual Altomontana” following the official Brazilian classification— Veloso et al. 1991). The plants were found on rock shallow crevices or bromeliad clusters on thin, organic soil, and among other shrubs and herbs. The inselbergs where these plants have been found (“Alto Rio Perdido”, “Alto Santa Maria”, “Pedra Alegre”, “Pedra da Onça” and “Toma Vento” in Santa Teresa, and “Alto Misterioso” in São Roque do Canaã) do not belong to any conservation unit ( Figure 3 ).

Phenology:—Collected with flowers and fruits during the whole year.

Conservation status:—This species can be considered as “Criticaly Endangered”, according to IUCN’s category A2a (2012). The Area of Occupancy is about 20.000 km 2, and the Extent of occurrence is 54.522 km 2. The vegetation in some of the places where it is found have been grazed by cattle or replaced by cultivation, mostly close to Santa Teresa and São Roque do Canaã. These plants apparently do not occur inside protected areas.

Etymology:—The epithet honors Ludovic Jean Charles Kollmann, botanist and important plant collector in Espírito Santo, including several new species of Pleroma .

Affinities:— Pleroma kollmanniana is similar to Tibouchina heteromalla , especially by the flowers with purple petals, with a white base, and by the antepetalous stamens with connective and appendages with glandular trichomes. It differs from T. heteromalla by the characters pointed in the diagnosis, and also by the setulose style (vs. glabrous in T. heteromalla ). Pleroma kollmanniana is also similar to Tibouchina villosissima ( Triana 1873: 43) Cogniaux (1885: 330) due to the leaves with 7 nerves and sericeous adaxial surface. Pleroma kollmanniana differs from T. villosissima var. villosissima by the strongly winged branches and sericeous hypanthium [vs. respectively not winged and glandulosesericeous in T. villosissima var. villosissima , this based on Claussen 556 (P!), from an unknown locality, Minas Gerais], and from Tibouchina villosissima var. petiolaris Cogniaux (1885: 331) by the shorter petioles, about 1.7–2.5 mm long in P. kollmanniana [vs. 50–100 mm in Tibouchina villosissima var. petiolaris , this based on the original description by Cogniaux (1885)]. Another similar species is Tibouchina grandifolia Cogniaux (1885: 335) , which has been recognized as a synonym of T. heteromalla by some authors ( Guimarães 1997, MELNET 2016, Guimarães 2016). Both have wide leaves (15.5–20.5 × 8.8–12 cm in P. kollmanniana and 11.5–20 × 7.1–11.8 cm in T. grandifolia ), but P. kollmanniana differs by the more pronounced wings on older branches (3.4–5.5 mm long vs. 0.9–1.4 mm in T. grandifolia ), and shorter petioles [1.7–2.5 mm long vs. 14–45 mm long in T. grandifolia , this based on Vauthier 49 (P!), from an unknown locality, Rio de Janeiro]. Tibouchina multiflora ( Gardner 1843: 351) Cogniaux (1885: 333) has also been recognized as a synonym of T. heteromalla ( Guimarães 1997, MELNET 2016, Guimarães 2016). It also has flowers with purple petals, with white bases, and stamens with connective and appendages with glandular trichomes. Pleroma kollmanniana differs from T. multiflora by the more pronounced wings on older branches (3.4–5.5 mm long vs. 1–1.3 mm in T. multiflora ), shorter petioles (1.7–2.5 mm long vs. 10.2–19.1 mm long in T. multiflora ), and larger petals [15.3–19.6 × 14–15.3 mm vs. ca. 7 × 6 mm in T. multiflora , this based on Gardner 409 (K!, NY!, P!), from “Serra dos Órgãos”, Rio de Janeiro].

Figures

FIGURE 3. Distribution maps of P. costatocalyx, P. kollmanniana and P. subsessilis.

FIGURE 4. Images of the holotype of Pleroma kollmanniana. A. Branch. B. Detail of the leaf indumentum (abaxial surface). C. Detail of the leaf indumentum (adaxial surface). D. Bracteole (abaxial surface). E. Petal (abaxial surface). F. Stamens. G. Gynoecium. H. Fruit (all from Meyer & Kollmann 2219 at MBML).

FIGURE 5. Living plant photos of Pleroma kollmanniana. A. Habit. B. Winged branches. C. Leaf (adaxial surface). D. Inflorescence. E. Flower bud. F. Flower. G. Detail of the stamens. (A by R. Goldenberg; B–G by F.S. Meyer).