Abstract Detail

Floristics & Taxonomy

Lopes Silva, Rafael Francisco [1], Silva, Anauara Lima [2], Agra, Maria de Fátima [3].

Using the morphology and leaf anatomy as a taxonomic tool for the distinction of three species of Tanecium Sw. emend L.G.Lohmann.

Tanaecium Sw. emend. L.G.Lohmann (Bignonieae, Bignoniaecae) is a monophyletic genus, with 21 species well supported by molecular studies. They are lianas and shrubs, morphologically variable, and distributed from Mexico and Antilles to Argentina, with subulate prophylls, and/or bromeliad-like on the axillary buds. This work was performed in order to find leaf anatomical characters with taxonomic significance to support the taxonomy of Tanaecium cyrtanthum (Mart. ex DC.) Bureau & K.Schum., T. dichotomum (Jacq.) Kaehler & LG.Lohmann, and T. parviflorum (Mart. ex DC.) Kaehler & LG.Lohmann). The study was carried out following the usual techniques in plant anatomy, and analyzed by light and scanning electronic microscopy. The plant material was collected from Pico do Jabre, Paraíba, Brazil. Two species are lianas, T. cyrtanthum and T. dichotomum, while T. parviflorum is a shrub, and only T. cyrtanthum has interpeciolar glands. The Leaves are 2-3-foliolate with entire margins in T. cyrtanthum and T. dichotomum, and 3-foliolate with 2/3 of the margin crenate in T. parviflorum. The corollas are pink and the stamens are included in T. dichotomum and T. parviflorum, and white with exserted stamens in T. cyrtanthum. The fruits are capsules linear and glabrescent in T. parvilforum, densely villous and flattened in T. dichotomum, and sparse-lepidote and cylindrical in T. cyrtanthum. The epidermal anticlinal cell walls are sinuous on the both surfaces of T. dichotomum and T. parviflorum, and on the abaxial surface of T. cyrtanthum. We observed seven types of stomata (anisocytic, anomocytic, anomotetracytic, brachyparacytic, hemiparacytic, paracytic and staurocytic), and different types were present on the same surface: five types in T. cyrtanthum, and six types in T. dichotomum and T. parviflorum. The border is acute in T. dichotomum, rounded in T. parviflorum, and varied from acute to rounded in T. cyrtanthum. The mesophyll is dorsiventral in all species. The midrib is biconvex with a vascular bundle in arc-shaped in T. cyrtanthum, and in U-shaped in T. dichotomum and T. parviflorum. The petiole is circular in T. cyrtanthum and T. dichotomum, and semicircular in T. parviflorum. The vascular system is collateral, with a circular-shape in T. cyrtanthum and T. dichotomum, and depress-obovate in T. parviflorum. The anatomy of the petiole, border, mesophyll, vascular system of the midrib, and the different types of stomata constitute a set of anatomical characters, which support the taxonomic distinction of the studied species of Tanaecium.

1 - Universidade Federal de Pernambuco, Departamento de Botânica, Rua Professor Moraes Rego, s/n. Cidade Universitária, Recife, Pernambuco, 50.670-901, Brazil
2 - Universidade Federal da Paraíba, PgPNSB - Centro de Ciências da Saúde, João Pessoa, Paraíba, Brasil
3 - Universidade Federal da Paraíba, R. Tab. Stanislau Eloy, 41-769 - Conj. Pres. Castelo Branco III, João Pessoa, Paraíba, 58050-585, Brasil

Keywords:
Bignonieae
Bignoniaceae
integrative systematics
Lamiales
leaf anatomy.

Presentation Type: Poster
Session: P2, Floristics & Taxonomy Posters
Location: Virtual/Virtual
Date: Tuesday, July 20th, 2021
Time: 5:00 PM(EDT)
Number: P2FT013
Abstract ID:916
Candidate for Awards:None