alternans Leach, 1815:383.

Neotype (NMNH); neotype locality: Fat Hog’s Bay, Tortola, British Virgin Islands; Shelley (2002) designated a neotype from a British possession because the species was named by Leach and likely came from such rather than a territory of another European country.

Original rank: species. Current rank and status: valid species (Kraepelin 1903; Brölemann 1909; Attems 1930; Bücherl 1939, 1942 a, 1974; Shelley 2002).

Anatomical illustrations: Shelley (2002, figs. 43–48).

Distribution: the southern tip of Florida, USA (Collier, Dade, & Monroe cos.) to at least northern South America. Scolopendra alternans is common in the Caribbean and is known from the Bahamas (Andros, Bimini, Cat, Exuma, Little Inagua, New Providence, Salt and Rum Cays, & San Salvador), Cuba, Hispaniola (both the Dominican Republic & Haiti), Puerto Rico, U. S. Virgin Islands (St. John, St. Thomas, & St. Croix), British Virgin Islands (Caiba, Guana, Pete’s I., Sombrero I., & Tortola), St. Barthélemy, St. Eustaceus, St. Kitts, Saba, Barbuda, Antigua, Montserrat, Guadeloupe, Dominica, St. Lucia, & Trinidad (references summarized in Shelley (2002)). In South America, it has been recorded from Venezuela & Brazil (Shelley 2002), and while the northern coast of Venezuela is plausible for S. alternans, its occurrence in Brazil requires corroboration. Map: Shelley (2002, fig. 49 in part, occurrence in the continental US).

Remarks: Scolopendra alternans is the only indigenous species of Scolopendra in the New World that lacks the anterior transverse sulcus on the 1st tergite, a characteristic of Old World species. It has always been credited to Leach, 1813, in vol. 7 of the Edinburgh Encyclopedia, which is the citation provided by Leach (1815). I (Shelley 2002) gave 1813 as the publication date but could not provide a page because that volume of the Encyclopedia is not available in the US. Through the courtesy of my colleague A. Minelli, I have finally seen a copy of this work, and S. alternans is not mentioned therein. The actual publication date therefore reverts to 1815, where Leach named this species and provided a descriptive sentence in the account immediately preceding that of S. subspinipes.