Miriamin, a defensive diterpene from the eggs of a land slug ( Arion sp.)

Abstract

The eggs of the land slug Arion sp. contain a diterpene, miriamin, characterized as a polyoxygenated geranylgeraniol derivative. In bioassays with a coccinellid beetle, Harmonia axyridis , miriamin was shown to be potently antifeedant, indicating that the compound plays a protective role in nature. It is suggested that mucilaginous soil-inhabiting organisms, given their intense exposure to pathogens and predators, may be a rich source of chemical defensive agents.

The multicolored Asian lady beetle, Harmonia axyridis: A review of its biology, uses in biological control, and non-target impacts

“…Some prey appear to be chemically protected from predation. A diterpene from the eggs of the slug, Arion sp., (Schroder et al, 1999) and an alkaloid from the pupae of the Mexican bean beetle, Epilachna varivestis, (Rossini et al, 2000) both act as antifeedants to H. axyridis.…”

Novel Animal Defenses against Predation: A Snail Egg Neurotoxin Combining Lectin and Pore-Forming Chains That Resembles Plant Defense and Bacteria Attack Toxins

“…Motionless and often conspicuous, eggs are highly vulnerable to both predators and parasites [2] and their high nutritional value makes them subject to intense predation. Consequently, many invertebrates defend their eggs by endowing them with deterrent chemicals as has been well documented in insects that sequester toxic compounds from plants [3]–[5] and in some terrestrial and marine gastropods [6], [7]. There are, however, a few eggs that are winning in the “arms-race” and escape intense predation such as the aerial egg clutches from the aquatic apple snail Pomacea canaliculata (Lamarck, 1822) (Caenogastropoda, Ampullariidae) which, while filled with large amounts of carbohydrates and storage proteins (perivitellins) [8], have only one reported predator worldwide, the fire ant Solenopsis geminata (Fabricius, 1804) [9].…”

Poisons, toxungens, and venoms: redefining and classifying toxic biological secretions and the organisms that employ them

“…Several marine invertebrates and fishes appear to sequester toxins from their diet (Kvitek, 1991;Becerro, Starmer & Paul, 2006;Derby & Aggio, 2011), as do some insects (Nishida, 2002;Opitz & Muller, 2009) and several birds (Dumbacher, Spande & Daly, 2000;Dumbacher et al, 2004;Dumbacher, Menon & Daly, 2009). Maternal transfer of toxins to eggs, presumably conferring protection to the eggs and/or larvae, has been documented in marine invertebrates and fishes (Pawlik et al, 1988;Lindquist, Hay & Fenical, 1992;Noguch & Arakawa, 2008), terrestrial invertebrates including insects (Schroeder et al, 1999;Bezzerides et al, 2004;Nikbakhtzadeh et al, 2012), and amphibians (Akizawa et al, 1994). Symbiotic bacteria can synthesize toxins for their metazoan host, as documented in some marine invertebrates and fishes (Chau, Kalaitzis & Neilan, 2011).…”