Epimorphosis and repair processes of schistomelic pedipalps and walking appendages in Tegenaria atrica (Araneae, Agelenidae)

Experimental studies of regeneration and repair processes of schistomelic walking legs and pedipalps in the early postembryonal stages of Tegenaria atrica were carried out in two parts. In the first part changes in the structure of appendages were produced by exposing the developing embryos to alternating temperatures (14 and 32. C, changing every 12 hours) as teratogenic factor. In the second, principal, part of studies after amputating a given fragment of a larval schistomelic appendage the appearance, then the growth and development of the external regenerates were observed. The completion of epimorphosis of the pedipalps followed at nymph IV stage (after four post-larval moults) that of the walking appendages in most cases at nymph V stage (after five post-larval moults). In control spiders repair processes were noted, which proceeded at a rate comparable to regeneration processes.