In: Phyton 59, Fasc. 1 (2019): S. 27-33 DOI: 10.12905/0380.phyton59-2019-0027 Published online on 10 Oktober 2019

First report on effective pollination of Masdevallia floribunda, M. tuerckheimii and their hybrid (Orchidaceae-Pleurothallidinae) by Zygothrica fruit flies (Diptera-Drosophilidae) in Guatemala

Monika M. Lipinska

Key words: Masdevallia, M. floribunda, M. tuerckheimii, Orchidaceae, Pleurothallidinae, orchids, pollinators, pollen transfer, pollination syndromes, myophily, Neotropics, Guatemala, biodiversity.

Summary
Lipinska M. M., Archila Morales F. L., Gilka W., Beuk P. L. Th. & Szlachetko D. L. 2019. First report on effective pollination of Masdevallia floribunda, M. tuerckheimii and their hybrid (Orchidaceae-Pleurothallidinae) by Zygothrica fruit flies (Diptera-Drosophilidae) in Guatemala. – Phyton (Horn, Austria) 59 (1–2): 27–33, with 3 figures.

The first report on pollination of two Neotropical orchid species, Masdevallia floribunda Lindl., M. tuerckheimii Ames and their hybrid by fruit flies is presented. Two presumably undescribed species of the genus Zygothrica, tentatively named as Zygothrica spec. 1 and spec. 2, were observed as pollinators. The distinct hypercephaly in the examined males, the transparent wing membrane lacking infuscations or markings in both sexes indicate that Zygothrica spec. 1 is a member of the caudata subgroup of the dispar species group. The exact affinities of Zygothrica spec. 2 are uncertain, but this species resembles Z. mesopoeyi Burla. Our observations evidenced that the Masdevallia flowers attract both males and females of Zygothrica, and that both can carry the pollinia. The Estación Experimental de Orquídeas de la Familia Archila, a seminatural plantation located in a cloud forest of Guatemala, is a place of intense pollination activity by Zygothrica adults on the flowers of the two Masdevallia species, which also leads to effective and frequent hybridization.