4.2. Morphological implications and evolutionary patterns
Different analyses chiefly disagree on the basal part of
the tree, outgroup relationships and theridiid monophyly.
The Theridiidae is an extremely diverse family,
and instances of non-monophyly as a result of a few odd
taxa incorrectly placed in the family might be expected.
However, is it likely that Phoroncidia, a genus with
many classic theridiid features, is not a theridiid?
Phoroncidia, shares many theridiid synapomorphies,
e.g., absence of a basal, ectal paracymbium, distal
cymbial hook present and involved in cymbial-lock
mechanism, and grossly flattened aggregated gland
(AG) spigots. On the other hand, Phoroncidia lacks
some typical theridiid features: male palpal tibial rim
regularly and strongly hirsute and facing palpal bulb,
abdominal stridulatory picks, and theridiid-type tarsal
comb. It is definitely aberrant, and although morphology
supports its placement within theridiids, its exact
phylogenetic position remains inconclusive.