How many exonucleases have been discovered?

[Ludvig Mortberg]

I'm interested in exonucleases. I'm trying to find out how many have
been discovered. I know of the following six, but there are probably
more;

Venom phosphodiesterase

Spleen phosphodiesterase

E. coli exonuclease I

E. coli exonuclease III

E. coli exonuclease VII

Phage lambda exonuclease

Any clues of more exonucleases? Please provide names of them and
references.

Thanks in advance!

Ludvig Mortberg