Arachnids (spiders, scorpions, and their relatives) are a secondary fascination of mine. This species from the southern coast of Madagascar has a particularly unusual habit. I was curious the first time I saw 'empty' snail shells hanging in coastal scrub (see those two white specks in pic #1). Each shell was measured at 2+1/4" long (5.7 cm long); some were attached over one meter above ground level. Pic #2 shows a close-up of one and how it's suspended by silky threads, and how the opening is also silk-lined. Back in 1997, I saw a spider protruding from one of these shells at night, so I knew what must have attached it there. I was back in the same region in November 2003 and decided to get a better look at a shell's occupant - pic #3, some kind of 'wolf' spider. >>> * If anyone seeing this has any info to add about identification or habits of this creature, PLEASE contact me at: firstname.lastname@example.org . A couple things I can add to the story is what I found inside two other shells I broke open. One had approximately 8 smaller live spiders (of the same species, I believe) inside the core section, and another shell harbored only a live cricket.
The obvious question is "How does the snail shell get up into the bush?" My guess would be that the spider has some kind of special system involving its silk to haul or pulley the shell up. This would, of course, be fascinating to actually observe.
* I've learned, thanks to Dr. Diana Silva Davila at the California Academy of Sciences in San Francisco, that this is most likely Olios coenobita, described by Fage in 1926 from the same general region.
* Thanks also to Neil Fahy for additional notes on this relationship, including an ID of the snail - Leucotaenius favannii (Lamarck, 1822) (Acavidae), a ground-dwelling species.