MESOZOIC PARASITES

[darren.naish@port.ac.uk]

Rachel Clark asked if there were ticks that may have bitten Mesozoic
dinosaurs. Sorry, I don't know, but I think that yes there were, 
simply because arachnids did a lot of diversifying in the Palaeozoic 
(e.g. opilionids (=harvestmen or phalangidans) debut in the 
Carboniferous, scorpions were around in the Silurian). The earliest 
fossil tick I am aware of is from the late Eocene.

I understand also that soft internal parastites - nematodes, 
platyhelminths, cestoideans (=tapeworms) - have no or only Recent 
fossil records, but are thought to have originated way way before the 
Mesozoic (e.g. in the Cambrian) and hence would have parasitised 
Mesozoic animals. I'm way out of date in what I know of things 
without backbones though, so if any of you invert workers can bring 
this up to date I'd be interested.

Fleas are known from the Cretaceous, and I recall a bizarre 
long-legged arthropod described by Ponomarenko in the 1970s. He 
thought this animal was a pterosaur parasite, largely on the basis 
of a similarity to bat parasites. 

So, yes Rachel, dinosaurs were probably troubled by pretty much all 
the parasites that exploit tetrapods today.

"Mmm-mm, something round here sure smells good - - oh! It's me!"

DARREN NAISH
darren.naish@port.ac.uk