EGG SAC STRUCTURE OF ZYGIELLAX-NOTATA (ARACHNIDA, ARANEIDAE)

Hunting with sticky tape: functional shift in silk glands of araneophagous ground spiders (Gnaphosidae)

“…2J) is regarded as one of the key innovations of araneomorph spiders that presumably highly enhanced the versatility of silk use and made the building of webs in a 3D space possible (Coddington and Levi, 1991). Draglines play a role in protecting the spider against unpredicted falls (Ortlepp and Gosline, 2008), controlling jumps (Chen et al, 2013) and on-water locomotion (Gorb and Barth, 1994), assisting navigation in webs (Barth et al, 1998), as elemental structures for webs (Denny, 1976), egg sac suspension (Gheysens et al, 2005), shelter building and intraspecific and interspecific communication (Leonard and Morse, 2006;Tietjen, 1977). Hence, a deviation from the usual ALS configuration (single large MA and an array of multiple small PI spigots) is extremely rare among araneomorph spiders (Coddington, 1989;Coddington and Levi, 1991;Eberhard, 2010;Murphy and Roberts, 2015).…”

Possible functional significance of spigot placement on the spinnerets of spiders

“…They seem to be slightly sticky when they emerge, because some lines in egg sacs are covered with liquid (Kullmann 1975 on an araneid, a mimetid and a deinopid; Stern & Kullmann 1981 on a theridiid), and they very frequently adhere at least weakly to each other, even though the spider only briefly dabs her abdomen to the egg sac during construction; the dabs are not accompanied by short pauses, as when piriform discs are produced (Kullmann 1961;Gheysens et al 2005;Moya et al 2010). It thus appears that piriform silk is not used to hold sticky cylindrical gland lines together; this is consistent with morphology, as the cylindrical gland spigots are downstream with respect to the piriform gland spigots (Fig.…”

Egg sac construction by folding dead leaves in Pozonia nigroventris and Micrathena sp. (Araneae: Araneidae)

“…Protection is not absolute, and spider eggs frequently suffer high mortality from organisms such as ants, wasps, flies and birds (Austin 1985;Hieber 1992). Egg sac construction varies widely among different spider taxa (Kullmann 1961;Robinson & Robinson 1973, 1976Eberhard 1980;Manuel 1984;Austin 1985;Levi 1985;Barnes et al 1992;Bukowski & Christenson 1997;Guarisco 2001;Gheysens et al 2005). However, detailed descriptions of egg sac construction are lacking for many groups.…”