I was moved by my friend Joe Boggs post about oleander aphids on milkweeds (Asclepias spp.) to add a little to the mix, mainly because I wrote earlier about butterfly weed (Asclepias tuberosa) and because I took a number of pictures of milkweeds in the past few weeks and in previous years. They are quite beautiful with their reflexed corolla (group of petals) and elaborate horn and hood structures, their silky fibers (coma) used for life preserver flotation in World War II and pillows and comforters today, and for their relationship with Monarch butterflies.
As Joe noted, Asclepias is a North and South American genus in the dogbane family, the Apocynaceae, though it once headed up its own eponymous family, the Asclepidaceae. There are over 100 species in Asclepias, and the genus is joined in the family by Canthranthus and Vinca, the periwinkles, and as Joe notes, Nerium oleander, our southern and western U.S. poisonous landscape plant. Poisonous glycosides are produced by many milkweeds, yet as is often the case, the dose makes the poison and Asclepias is often touted in folklore for various purgative and other medicinal functions.
Linnaeus himself codified our native milkweed as Asclepias syriaca (though the plant is not from Syria) in 1753, naming the species after Asclepius, the Greek god of healing. The classic rod of Asclepius and of medicine focusing on patients and used by many medical organizations worldwide is a single snake twined around a wooden staff. Some medical organizations use the caduceus with two intertwined snakes and wings, which represents the Greek god Hermes (the Roman god Mercury, and the Ohio god Dan Herms).
Anyway, enjoy the recent pictures of milkweed flowers and Monarch butterflies from Virginia, milkweed beetles (the red milkweed beetle (Tetraopes tetrophthamus) and a greenish-blue beetle (that may be the dogbane beetle (Chrysochus auratus) from Orrville, Ohio, and milkweed “silk” or “coma” from Rittman, Ohio.