Some comments on the anatomy of spiders
Author
Palmgren, P.
text
Ann. Zool. Fennici
1980
17
161
173
http://antbase.org/ants/publications/Palmgren1980/Palmgren1980.pdf
journal article
Palmgren1980
Nephila clavipes
and
maculata
The
Nephila
species (Figs. 5-9) have a very much stronger chelicerai m.antero-medialis verticalis than
Azilia
and thus resemble the
Araneidae
earlier dissected by me.
N.clavipes
has a cleft suspensor IV,.
N.maculata
a single one; this feature is apparently of little taxonomic value.
The anterior tergo-pedipalpal muscle [pa) is double-fanned in
N. clavipes
, but triple-fanned in.AT.
maculata
. The m. tergo-coxalis anterior profundus (c,, "anterior rotator") of the first leg arises in JV.
clavipes
as two broad portions; in
N.maculata
one of the portions is very narrow. None of the
Nephila
species has caecal pouches protruding between the tergo-coxal muscles. In JV
clavipes
the dorsal pouch is short. In JV.
maculala
it extends to the base of the chelicerae and sends a very narrow tube into them, a feature reminiscent of the
Tetragnathidae
. In this species the poison gland is short, while in JV.
clavipes
it extends to the dorsal apodeme. I have previously drawn attention to the apparent competition for space between the poison glands and the dorsal caecum.