Oulema palustris
Creators: name: Eiseman, Charles S.
name: Feldman, Tracy S.
name: Palmer, Michael W.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Chrysomelidae
Oulema
Oulema palustris

description: Oulema palustris (Blatchley)
(Figs. 87–88, 157)
Reared specimens. MASSACHUSETTS: Franklin Co., Northfield, Old Wendell Rd. (42.637210, -72.420895), 13.vii.2017, em. 4.viii.2017, C.S. Eiseman, ex Cirsium vulgare, # CSE4063 (4 adults, MLBM); Nantucket Co., Nantucket, Head of the Plains, 10.vi.2016, em. 1–13.vii.2016, C.S. Eiseman, ex Cirsium horridulum, # CSE2687 (10 adults, MLBM); NORTH CAROLINA: Durham Co., Durham, Pelham Road, 26.iv.2021, em. 1–4.vi.2021, T. S. Feldman, ex Cirsium vulgare, # CSE7038 (1 adult, MLBM); TEXAS: Wilson Co., Stockdale, Jackson Nature Park, 5.iii.2023, em. 27.iii.2023, C. Burrier, ex Tradescantia, # CSE8121 (1 adult, MBLM); 25.iii.2023, em. by 19.iv.2023, C. Burrier, ex Cirsium texanum, # CSE8119 (1 adult, MLBM).
Collected specimens. MASSACHUSETTS: Nantucket Co., Nantucket, Head of the Plains, 10.vi.2016, preserved 27.vi.2016, C.S. Eiseman, on Cirsium horridulum, # CSE2687 (2 larvae, MLBM).
Other collected mines. INDIANA: Newton Co., Lake Village, Conrad Station Savanna, 29.vi.2019, C.S. Eiseman & J.A. Blyth, parasitized larvae in Tradescantia ohiensis.
Photographed mines. IOWA: Allamakee Co., Red Oak Prairie (43.237064, -91.119050), 26.vi.2019, C.S. Eiseman, Cirsium discolor [vacated] (iNat 203287172); MARYLAND: Harford Co., Darlington, 13.vi.2018, J. Emm, Carduus nutans [larva] (BG 1537715); NEW JERSEY: Somerset Co., Martinsville, 1.vi.2019, S. Rall, Cirsium vulgare [larva] (iNat 26217815); Warren, 11.vi.2018, S. Rall, Cirsium arvense [vacated] (iNat 20021635); NORTH CAROLINA: Durham Co., Durham, Penny’s Bend on the Eno River, 18.vii.2022, cocoon 15.vii.2022, T.S. Feldman, Cirsium altissimum (BG 2146902).
Hosts. Asteraceae: Cirsium horridulum Michx., C. *texanum Buckley, C. *vulgare (Savi) Ten.; Commelinaceae: Tradescantia L. (Clark et al. 2004; Eiseman & Blyth 2022). Leaf mines presumably of Oulema palustris have also been found on Carduus nutans L. (Asteraceae), Cirsium altissimum (L.) Spreng., C. arvense (L.) Scop., C. discolor (Muhl. ex Willd.) Spreng., and T. ohiensis Raf. Adults of O. palustris have been found on Cirsium altissimum, C. arvense, C. discolor, and T. hirsutiflora Bush (Clark et al. 2004).
Biology. As reported by Eiseman & Blyth (2022), larvae form full-depth, irregular linear mines that often follow the leaf margin (Figs. 87–88). The rather liquid brown frass sometimes forms a distinct trail but may also be deposited in spots and irregular patches. Larvae occasionally wander over the leaf surface to initiate new mines, but they were never observed to feed externally. A mine is established by chewing a hole in the upper epidermis, and the frass trail sometimes begins a few millimeters outside of the mine entrance. Mature larvae burrow into soil (when available) and form white “cocoons” composed of numerous oblong globules of a frothy secretion.
Parasitoids. Adults of Bracon Fabricius (Braconidae) emerged from the two parasitized larvae collected from Tradescantia in Indiana (CSE5466, CNC).
description: Published as part of Eiseman, Charles S., Feldman, Tracy S. & Palmer, Michael W., 2024, New larval host records, parasitoid records, and DNA barcoding data for North American leaf-mining leaf beetles (Coleoptera: Chrysomeloidea), pp. 1-60 in Zootaxa 5549 (1) on pages 37-38, DOI: 10.11646/zootaxa.5549.1.1, http://zenodo.org/record/14387856