Zachary S. Rogers

A Revision of Malagasy Gnidia (Thymelaeaceae, Thymelaeoideae)1

Abstract A systematic revision of Gnidia L. is presented based on an analysis of morphological data. The circumscription of the genus adopted here includes Lasiosiphon Fresen. and excludes Atemnosiphon Leandri and Dais L. Six new combinations are made for species previously recognized as Lasiosiphon: G. ambondrombensis (Boiteau) Z. S. Rogers, G. hibbertioides (S. Moore) Z. S. Rogers, G. humbertii (Leandri) Z. S. Rogers, G. linearis (Leandri) Z. S. Rogers, G. occidentalis (Leandri) Z. S. Rogers, and G. perrieri (Leandri) Z. S. Rogers. Two names, G. daphnifolia L. f. and G. linearis, are resurrected from synonymy with L. madagascariensis (Lam.) Decne. and L. decaryi Leandri, respectively, and now pertain to more broadly circumscribed species. One new species, G. neglecta Z. S. Rogers, is described. These changes result in the recognition of 14 species, all endemic, making Gnidia the largest genus of Malagasy Thymelaeaceae. Lectotypifications are provided for 15 names: Dais gnidioides Baker, G. danguyana Leandri, L. bojerianus Decne., L. decaryi, L. decaryi var. erectus Leandri, L. decaryi var. littoralis Leandri, L. decaryi var. tenerifolia Leandri, L. dumetorum Leandri, L. hildebrandtii Scott-Elliot, L. humbertii Leandri, L. madagascariensis var. angustifolius Leandri, L. madagascariensis var. mandrarensis Leandri, L. occidentalis Leandri, L. perrieri Leandri, and L. pubescens (Lam.) Decne. var. multifolius Leandri. Each species is illustrated, mapped, and assigned a preliminary IUCN conservation status.

A new species of Weinmannia (Cunoniaceae: Cunonieae) from southern Ecuador

Two new species of Cunoniaceae, Weinmannia bradfordiana Z. Rogers and Weinmannia condorensis Z. Rogers are described and illustrated. Both sclerophyllous species are known only from their type localities and were collected from the Cordillera del Condor mountain range in the province of Morona Santiago, Ecuador.

Nomenclatural Notes on Garcinia (Clusiaceae) from Madagascar and The Comoros

ABSTRACT New results from phylogenetic analyses utilizing chloroplast and nuclear DNA markers agree with morphology in support of the unification of all of Rheedia L. and part of Ochrocarpos Thouars with Garcinia L. and show that species occurring in Madagascar and the Comoros fall into four separate lineages, which are designated here as informal species groups. An examination of Garcinia from these areas results in the recognition of 32 currently described species, all but one of which are endemic. The widespread African species, G. livingstonei T. Anderson, is noted for the first time to occur in Mayotte. Eleven new combinations are published here: G. ambrensis (H. Perrier) P. Sweeney & Z. S. Rogers, G. anjouanensis (H. Perrier) P. Sweeney & Z. S. Rogers, G. arenicola (Jumelle & H. Perrier) P. Sweeney & Z. S. Rogers, G. calcicola (Jumelle & H. Perrier) P. Sweeney & Z. S. Rogers, G. dalleizettei (H. Perrier) P. Sweeney & Z. S. Rogers, G. mangorensis (R. Viguier & Humbert) P. Sweeney & Z. S. Rogers, G. multifida (H. Perrier) P. Sweeney & Z. S. Rogers, G. parvula (H. Perrier) P. Sweeney & Z. S. Rogers, G. thouvenotii (H. Perrier) P. Sweeney & Z. S. Rogers, G. tsaratananensis (H. Perrier) P. Sweeney & Z. S. Rogers), and G. urschii (H. Perrier) P. Sweeney & Z. S. Rogers. Three new names, G. dauphinensis P. Sweeney & Z. S. Rogers, G. megistophylla P. Sweeney & Z. S. Rogers, and G. tsimatimia P. Sweeney & Z. S. Rogers, are provided for O. parvifolius Scott-Elliot, R. megaphylla H. Perrier, and R. pedicellata (Jumelle & H. Perrier) H. Perrier, respectively. Lectotypes are designated for 12 names: G. crassiflora Jumelle & H. Perrier, G. disepala Vesque, G. melleri Baker, G. polyphlebia Baker, G. verrucosa Jumelle & H. Perrier, O. ambrensis H. Perrier, O. macrophyllus O. Hoffmann, O. parvifolius, O. parvulus H. Perrier, O. tsaratananae H. Perrier, R. arenicola Jumelle & H. Perrier, and R. calcicola Jumelle & H. Perrier.

Staufferia and Pilgerina: Two New Endemic Monotypic Arborescent Genera of Santalaceae from Madagascar

Abstract Two new arborescent species of Santalaceae, both endemic to Madagascar, are described in the new monotypic genera, Staufferia Z. S. Rogers, Nickrent & Malécot and Pilgerina Z. S. Rogers, Nickrent & Malécot. Based on available molecular and morphological data, the new species are part of a clade formed with Pyrularia Michx. of Asia and North America, the Indo-Malesian genus Scleropyrum Arn., and the central and western African Okoubaka Pellegr. & Normand. Staufferia is distinguished morphologically from Okoubaka by the smaller inflorescences (4 to 10 vs. 50 to 100 flowers); smaller (1.8–2 × 1.1–1.6 cm vs. ca. 9 × 5 cm), obovoidal (vs. ellipsoidal) fruits; smaller (ca. 1.5 mm vs. 7–8 mm diam.), persistent perianth; thinner (0.5–1 mm vs. 15–20 mm thick), 5-sulcate (vs. smooth) exocarp; and thinner (ca. 0.5 mm vs. 3–4 mm thick), smooth (vs. deeply striate or alveolate) mesocarp. Pilgerina differs from Scleropyrum by the smaller inflorescences (8 to 23 vs. 60 to 100 flowers); pedicellate (vs. sessile) flowers; smaller (1.2–1.9 × 1.7–2.7 cm vs. ca. 3 × 2 cm), broadly transversely ellipsoidal to subspheroidal (vs. obovoidal to pyriform) fruits; and thinner (ca. 0.5 mm vs. 1.5–3 mm thick), smooth or finely striate (vs. deeply striate or alveolate) mesocarp. Both species are illustrated and assigned an IUCN preliminary conservation status of Least Concern (LC).

Two Distinctive New Species of Malagasy Garcinia (Clusiaceae)

Abstract During a recent survey of Malagasy Garcinia, we uncovered several herbarium collections sharing the general floral morphology of G. verrucosa, the sole member of the Xanthochymus Group in Madagascar but differing in a number of leaf, flower and fruit characters. Further inspection of specimens deposited in herbaria particularly rich in Madagascar collections led us to conclude that these unassigned collections represent two new species of Malagasy Garcinia, which we describe here under the names, G. capuronii and G. lowryi. Garcinia verrucosa differs from both new species by having larger (≥ 8 vs. ≤ 5 mm long) flowers and fruits without ridges or lobes. Garcinia capuronii is easily distinguished from G. lowryi by its larger (26–41.4 vs. 1–10.5 cm long), bullate (vs. plane) leaf blades, and strongly 8-ridged (vs. shallowly (3)4-lobed) fruits. Based on IUCN criteria, the widespread G. lowryi should be considered a species of Least Concern (LC), whereas G. capuronii, a species known only from its type, is provisionally assigned to the Critically Endangered (CE) category.

A new Species of Ludia (Salicaceae) from Madagascar's Eastern Littoral Forest

ABSTRACT Recent collecting efforts in Madagascars eastern littoral forest have yielded a new species, Ludia craggiana Z. S. Rogers, Randrianasolo & J. S. Miller (Salicaceae), which is apparently endemic to two sandy forest fragments located near Vohémar in northeastern Madagascar. This species is most similar to L. ludiifolia (H. Perrier) Capuron & Sleumer, but can be distinguished by its more robust young stems and spines, glabrous or rarely puberulent twigs, petioles, midribs, and pedicels, coriaceous leaves with midveins and secondary venation of similar thickness, 50 to 60 stamens with emarginate anther connectives, and by the minutely granular-papillose fruit surface. Ludia craggiana is illustrated and assigned a provisional conservation status of endangered.

Nomenclatural Notes on American Thymelaeaceae

Abstract The nomenclatural status of all published plant names applicable to American Thymelaeaceae at the rank of genus and below is evaluated. Thirty-two of the 256 published names at specific and infraspecific ranks require effective typifications. Lectotypes are designated for 29 names: Daphne lagetto Sw., D. macrophylla Kunth, D. occidentalis Sw., D. pillopillo Gay, Daphnopsis bogotensis Meisn., D. brasiliensis Mart., D. caracasana Meisn., D. caribaea Griseb. var. ecuadorensis Domke, D. coriacea Taub., D. decidua Domke, D. ekmanii Domke, D. ericiflora Gilg & Markgr., D. longifolia Taub., D. longipedunculata Gilg ex Domke, D. longiracemosa Gilg ex Domke, D. martii Meisn., D. purpusii Brandegee var. ehrenbergii Domke, D. racemosa Griseb., D. sessiliflora Griseb. ex Taub., D. zamorensis Domke, Goodallia guianensis Benth., G. guianensis var. parvifolia Benth., Lagetta funifera Mart. & Zucc. (epitype also designated), Linostoma albifolium Barb. Rodr., Lophostoma bolleanum Domke, Schoenobiblus coriaceus Domke, S. daphnoides Mart., S. ellipticus Pilg., and S. peruvianus Standl. Neotypes are designated for three names: Daphnopsis crassifolia (Poir.) Meisn. var. eggersii Krug & Urb., D. pseudosalix Domke, and D. selerorum Gilg.

Phaleria stevensiana: A Distinctive New Species of Thymelaeaceae Endemic to Sulawesi, Indonesia

Abstract. An undescribed species of Phaleria Jack from Sulawesi has been uncovered during ongoing herbarium studies of Thymelaeaceae and is still only known from the type. The species, P. stevensiana Z. S. Rogers, is endemic to a single limestone mountain in South Sulawesi and assigned a preliminary IUCN conservation status of Critically Endangered (CR). Morphologically, it is easily distinguished from the widespread P. octandra (L.) Baill. and P. capitata Jack by its linear-lanceolate leaves (length:width ratios ca. 11–20:1) and distinctive venation pattern, composed of ca. 29 to 35 pairs of secondary veins that diverge from the midrib of the blade at ± 90° angles; the contrasted species have much broader leaves with substantially fewer secondaries. Variation in other characters related to inflorescences, flowers, and fruits is also discussed, as is their taxonomic value. Moreover, all four species of Phaleria occurring in Sulawesi are allopatric, separated geographically and ecologically. The new species, overlooked in several herbaria since 1980, raises the number of Sulawesian Thymelaeaceae species to 10 and the total number of Phaleria species to ca. 25.

Six New Species of Danais Vent. (Rubiaceae, Danaideae) from Madagascar

Abstract Taylor, C. M. & Z. S. Rogers (2013). Six new species of Danais Vent. (Rubiaceae, Danaideae) from Madagascar. Candollea 68: 167–180. In English, English and French abstracts. Danais Vent. (Rubiaceae, Danaideae) comprises about forty species of woody climbing plants, with most of them found in Madagascar. Recent exploration there has documented six new endemic species that are described, illustrated, and mapped here: Danais antilahimenae C. M. Taylor, Danais disticha C. M. Taylor, Danais laciniata C. M. Taylor, Danais masoalana C. M. Taylor, Danais rakotovaoi C. M. Taylor, and Danais randrianaivoi C. M. Taylor. All six occur in humid vegetation and qualify as threatened based on preliminary IUCN conservation assessment (one “Critically Endangered”, four “Endangered”, one “Vulnerable”).

Dos Especies Nuevas de Weinmannia (Cunoniaceae) de los Bosques Montanos en La Paz, Bolivia

ABSTRACT A recent investigation of Weinmannia L. (Cunoniaceae) material collected from the Yungas region of La Paz, Bolivia, has uncovered two new species, W. davidsonii A. Fuentes & Z. S. Rogers and W. yungasensis A. Fuentes & Z. S. Rogers, both endemic to the area. Weinmannia davidsonii is similar to W. bangii Rusby but differs most obviously by the tomentose (vs. glabrous) ovary and denser pubescence of the leaves. Weinmannia yungasensis is close to W. dryadifolia Moricand ex Seringe but is distinguished most notably by the leaves that are up to 5-foliolate (vs. up to 3-foliolate), the larger simple leaves (0.9–3 × 0.8–2.5 cm vs. 1–2 × 0.6–1.2 cm), the glabrous (vs. pubescent) stipules, and the lax (vs. congested) longer inflorescences ((2–)3.5–5.5 cm vs. 1–3(–3.5) cm). Both species belong to section Weinmannia L.