About the Cover
Cover
Conus is the most species-rich genus among the gastropods. It has more than 500 members, nearly all of which are venomous predators that are highly selective about their prey. Each species has evolved unique peptide toxins with appropriate specificities that typically permit hunting of worms, other snails or fish, and often even certain types of these organisms. As Julia Stewart and William F. Gilly describe in their article on page 146 of this issue, Conus californicus is highly unusual in that it attacks and consumes all of the above prey types (see online video clips). This generalist hunting strategy is accompanied by an ability to adapt to new types of prey in a relatively short time, a feature unknown in other Conus species. Molecular phylogeny studies have revealed that C. californicus is distantly related to other members of the genus, so this degree of adaptability may be unique.
The cover photo shows Conus californicus actively hunting after being aroused by the addition of a worm to its tank (not illustrated). The highly mobile proboscis is the pearly white structure protruding to the right. Toxins are injected into a victim through a barbed, tubular dart (a modified radular tooth) that is fired from within the tip of the proboscis at high speed (see Schulz et al. video at <www.biolbull.org/supplemental/>).
The inset in the cover figure is a scanning electron micrograph of a tooth from Conus californicus. Its morphological features are a novel blend of those found in other Conus species that specialize in single prey types. The snail is "standing" on the posterior end of its foot and scanning the environment for cues, presumably chemical ones, to the location of the prey. Shell length is about 4 cm; diameter of the tooth below the barbs is about 0.05 mm.
Credits: Photo of snail by Todd Anderson, Stanford University. Micrograph of tooth by Ed Urban, Johns Hopkins University. Cover layout by Beth Liles, Marine Biological Laboratory.
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Copyright © 2006 by the Marine Biological Laboratory.
