J Syst Evol ›› 2021, Vol. 59 ›› Issue (4): 698-725.DOI: 10.1111/jse.12741

• Research Articles • Previous Articles     Next Articles

Monograph of Carex section Schiedeanae (Cyperaceae): Unexpected taxonomic and ecological diversity in a Mexican sedge clade

Anton A. Reznicek1*, María del Socorro González‐Elizondo2*, Marlene Hahn3, Mira Garner3, and Andrew L. Hipp3   

  1. 1 University of Michigan Herbarium, 3600 Varsity Drive, Ann Arbor, MI 48108, USA
    2 CIIDIR Instituto Politécnico Nacional, Sigma 119 Fracc. 20 de Noviembre II, Durango, Dgo 34234, Mexico
    3 The Morton Arboretum, 4100 Illinois Route 53, Lisle, IL 60532, USA
  • Received:2020-08-30 Accepted:2021-02-25 Online:2021-03-13 Published:2021-07-01

Abstract: Carex section Schiedeanae (subg. Euthyceras) has long been thought to comprise at most five species of Mexican sedges. Our morphological studies in the field and herbarium, however, supported by more recent DNA sequencing work, demonstrate that the section is, in fact, three times as species-rich, making it one of the largest sections in Mexico. Its 15 species range from Chihuahua to Tamaulipas south to Veracruz and Oaxaca; a single species, Carex muriculata, extends into the United States. The section has unusual inflorescences with simple (except in Carex complexa), uniformly androgynous, sessile spikes, utriculiform cladoprophylls, and perigynia with a unique combination of pubescence types composed of papillae; unicellular, simple hairs; and (in many species) multicellular tubercles. We recognize five previously described species (C. muriculataCarex perstrictaCarex schiedeana, Carex stellata, and Carex vizarronensis) and describe 10 additional species (Carex angustilepis, Carex cabralii, Carex complexa, Carex dentata, Carex gypsophila, Carex mesophila, Carex paneroi, Carex planilamina, Carex revoluta, and Carex tehuacana). We have expanded the morphological features used in the section to include particularly anther, staminate scale, and style features, and more detailed micromorphology of the perigynia, especially indumentum. In total, 13 of the 15 species recognized herein, with a total of 32 individuals, were examined for ETS and ITS for phylogenetic reconstruction. Phylogenetically, the xeric species (plus C. paneroi) form a grade leading to a clade of the more mesophytic species adapted to forest understories, plus the unique cliff dwelling C. complexa.

Key words: endemism, Mexico, new species, phylogeny, Sierra Madre, systematics, taxonomy