Weedfish eats shrimp at dusk; Carrickalinga SA 26-03-2011
Strange though it seems,I’m pretty sure the shrimp being eaten by the weed fish in this image is a common rock pool shrimp (Paleaemon serenus) which I have observed on a few other snorkels at the same site to be almost touching similarly common weed fish of same species and at these times the fish appeared to adopt a cleaner client posture.
As per another comments trail on this website by me under the image of a smooth toadfish also at same site,there is no longer any doubt that this shrimp species does at times clean smooth toadfish,and very little doubt they also clean zebra fish,yellow eye mullet,and probably quite a few other inshore and intertidal rock reef fish species,I believe they probably know when it is safe to clean small Clinid fish species like this H.perspicillatus without being at risk of being eaten.
Something to do with time of day or night,tides,and similar variables,along with,of course,the characteristic and often quite unmistakable client poses that all known client fish species here in South Australia adopt whether they are requesting cleaning by a cleaner cling fish host or a southern banded cleaner shrimp (Periclimenes aesopius) which is a dedicated cleaner and has a very different appearance and colors than the rock pool shrimp.
So I can conclude by stating that I am now convinced that the exceedingly common rocky intertidal shrimp species P.serenus is a facultative cleaner of a wide variety of inshore fish (and that includes occasional visitors such as yellow eye mullet which are a schooling inshore species that is not site associated to any significant degree and roams widely along our shores but often seeks shelter for the night in shallow rock pools and channels in the intertidal zone .)
Source: via David Muirhead on Oceandiscover