Mexichromis macropus

Karl Fehlauer Mexichromis macropus Grain Terminal, Rockingham, Western Australia Approx 15mm in lenght, depth 4m

Mark Farrer love the color well done Karl Fehlauer

Graham Abbott Another West Australian nudibranch that caught me out, is this just a variation on Mexichromis macropus?

Sonja Ooms I think you are right about that one.

Karl Fehlauer Mexichromis macropus - 10mm in length Canon G12 twin YS 110 Alpha strobes & a x6 macro wet lens F6.3 1/320 ISO 100 Ammo Jetty - Western Australia Vis - 4m

Karl Fehlauer Mexichromis macropus Canon G12 twin YS110 Alpha strobes & a x3 M67 wet lens Vis - an awesome 3m!! Grain Terminal Rockingham

IkeBe Ph 1/2 inch long taken at a depth of 30 ft. Anilao, Batangas

Jun V Lao mexichromis_mariei ?

Gary Cobb I would stick with Mexichromis macropus Rudman, 1983

Jamie Coote Tumby Bay jetty SA.

Ashley Missen Nice Mexichromis macropus Jamie Coote

Chandy de Wit Came across these three on a dive today, wondering if there is any possible explanation?

Rahul Meh-unpronouncable Hypselodoris infucata and what are the other two?

Chandy de Wit More interested in the behaviour? The others are Mexichromis macropus...

Rahul Meh-unpronouncable Initial guess would be communal feeding, though a simple explanation, there are so many nudis with such specific food sources that this behaviour would be interesting to see food preferance choicing over interspecies behavioural patterns.

Chandy de Wit Perfect explanation, though not sure the contact would be necessary since there was quite a large patch of the substance they were on?

Rahul Meh-unpronouncable Perhaps slime trails would answer that bit as nudi that prey on other nudis use slime trails to lead them to their prey, so perhaps though it isnt a predator prey interaction, the hypselodoris is still gaining some information from the slime trail of the others. That this is just a guess, it may explain the close proximity.

Chandy de Wit Makes sense :) so many questions with Nudibranchs :)

Gary Cobb Groupings happen with the same food source. The Hypselodoris is to be questioned! If the animal is fm Australian waters it won't be H. Infucata it would be H. obscura. And if the gills are triangular it would be H. kanga

Chris Cunnold Hi all, what 's the chance that the Hypselodoris is H.saintvincentius? As this is from West Australia.

Chandy de Wit Sorry it's from SW Western Australia, have been calling it Hypselodoris Saintvincentius ??? Though apparently that is questionable?

Chris Cunnold Really? I'm interested in this development, do you know where to point me for the info? I found this http://web.archive.org/web/20130123090304/http://www.seaslugforum.net/find/hypssain

Chandy de Wit I've been calling it Hyp. saintvincentius forever but it's in "Nudibranchs of the World"....

Chandy de Wit And the pic in Neville Coleman's Encyclopaedia doesn't look like it has any yellow spots, so I'm confused......

Sue Myburgh Good to see they are all coming back.

Gary Cobb Yes after a little closer look you may be right the left animal is Hypselodoris saintvincentius the body and rhinophores match, it would be mic to see the gills. Good catch Chris!

Chandy de Wit

Chandy de Wit Hypselodoris saintvincentius, funny, wasn't woundering this at all at the beginning of this post but when Rahul said infucata I found that I have three publications that are saying the same......

Rahul Meh-unpronouncable The degree of difference is often so minute, its hard to see where one species stops and another begins

Gary Cobb For one thing Hypselodoris saintvincentius has red gills with white specks.

Gary Cobb Here are the gill differences between 3 species that look very similar. Hypselodoris infucata has gills with an outer edge has that has one red line, H. kanga has gills are triangular in cross-section (the outer edge has two red lines) and H. saintvincentius has gills similar to H. infucata but with white specks.

Chris Cunnold That's great Gary , a definitive way to ID them, I'm going to have to go back over my images to check.

Gary Cobb Hypselodoris obscura has the single outer red line too BUT is only found on the east coast of Australia (endemic)

Chandy de Wit Thanks Gary Cobb, pretty sure I've only ever seen saintvincentius, the markings and colours of the others also seem quite distinctively different.

Gary Cobb You're quite welcome!