Abstract Detail

Systematics

Szubryt, Marisa [1], Neubig, Kurt [2], Urbatsch, Lowell [3], Vargas-Rodriguez, Yalma [4].

Morphological, molecular, and biogeographic evidence for the recognition of Euthamia hirtipes and E. scabra (Asteraceae, Astereae).

The genus Euthamia (Asteraceae: Astereae) encompasses several species of ecologically important suffrutescent, rhizomatous herbs distributed throughout North America. Species circumscription within Euthamia has varied greatly owing to limited morphological differences among species. The grass-leaved goldenrod Euthamia graminifolia is particularly problematic given its variation in pubescence, resin pit abundance, and leaf dimensions throughout its wide range. Both the scabrous, broad-leaved plants in the southern Gulf Coast-Florida Panhandle region and the largely glabrous plants with relatively large capitula along the east coast from Florida to New Jersey have been historically incorporated into a broad definition of E. graminifolia. However, molecular (nuclear ribosomal and whole chloroplast genome), morphological, and biogeographical data indicate that the Gulf Coast and Atlantic Coast are two parapatric and distinct species, Euthamia scabra and E. hirtipes respectively, that hybridize in the Florida Panhandle and southern Alabama. This research provides insight into phylogeography, capacity for hybridization, and reticulate evolution within the genus. Euthamia graminifolia is polyphyletic with the inclusion of Gulf Coast and Atlantic Coast specimens, justifying the establishment of E. hirtipes and E. scabra as distinct species.

1 - 1125 Lincoln Drive Room 420, Carbondale, 62901, United States
2 - Southern Illinois University, Dept Of Plant Biology, 1125 Lincoln Dr., Life Science II, Room 420, Carbondale, IL, 62901, United States
3 - Louisiana State University, Biological Sciences Dept., Room 202; Life Sciences Bldg, Baton Rouge, LA, 70803.0, United States
4 - Apartado Postal 4-014, Calle Diaz Miron 444, Colonia La Loma, Sector Ref, Guadalajara, Jalisco, JAL, 44421, Mexico

Keywords:
systematics
Phylogenetics
biogeography
hybridization
taxonomy
Asteraceae
Astereae
Euthamia.

Presentation Type: Oral Paper
Session: SYS3, Systematics III: Asterids part 2
Location: Tucson G/Starr Pass
Date: Wednesday, July 31st, 2019
Time: 3:45 PM
Number: SYS3009
Abstract ID:465
Candidate for Awards:None