Dissertation - HQ

Appendix A
Undescribed Chaetodonthidae
Two specimen of a quite odd looking larva were captured on two
different occasions during the cruise around Tetiaroa, at several days
interval (see chapter 4 for details regarding sampling strategy). Both are
advanced stages and were identified as Chaetodontids due to the bony
head plates characteristic of the tholichthys stage of this family. They
are otherwise characterised by particularly long supra-ocular ridges,
horn-like, which protrude forward. In other species where those ridges
are extended, they are rather oriented perpendicular to the body, or
backward. Such “longhorn” specimen were already captured in French
Polynesia, around the atoll of Mururoa in 1977. A technical report of
the ORSTOM 318 contains a picture of at least four specimen, but they
were erroneously identified as Heniochus sp. and were not described.
Those specimen are nowhere to be found today.
Both specimen were photographed still alive, straight out of the nets,
onboard the ship. These pictures of somewhat low quality allow to see
their real colours (Figures A.1 and A.4). Several months after being fixed
in formalin, high quality photographs were taken by David G. Johnson
in the National Museum of Natural History, Washington (Figure A.2,
A.3, and A.5). Both specimen are now stored in 90% ethanol.
Morphometric measurements were performed on high resolution
side-view photographs, with the software ImageJ. Meristic counts were
performed on fixed specimen and on the same photographs (Table A.1).
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