FAMILY PLATYCEPHALIDAE — SCHULTZ 45 



ending posteriorly in a strong spine and on its ventral, anterior edge 

 a small spiny knob; 2 nostrils, anterior one projecting more than 

 posterior, both tubular; teeth in villiform band in both jaws, absent 

 on vomer and palatines; gill rakers short; membrane between spiny 

 and soft dorsal fin deeply emarginate, connected less than halfway 

 out from base of first soft ray. 



Color in alcohol. — Brownish with small black dots everywhere 

 except on fin rays, breast, and ventral parts of head. 



Ecology. — This species was most frequently encountered in the coral 

 Acropora, living in surf or near sui*f conditions or where the wave 

 action was generally strong. It was taken from ocean reefs in the 

 lagoon and from the channel reefs. 



Family PLATYCEPHALIDAE: Flatheads 

 By Leonard P. Schultz 



Identification of species referable to this family is extremely 

 difficult because there are numerous names available without adequate 

 figures and descriptions, especially of the cranial ridges and spines, 

 also lacking are important counts of scales and fin rays. To help 

 clarify the different groups of flatheads, a tentative key to genera was 

 attempted. This should be used with caution since some of the 

 species, especially those of Whitley's genera, were not available as 

 specimens. 



Since preparing the manuscript on this family, Matsubara and 

 Ochiai (Mem. Coll. Agric Kyoto Univ., No. 68, pp. 1-109, figs. 1-33, 

 pis. 1-3, 1955) have revised the Japanese species and presented a key 

 to genera. Their study, like mine, was handicapped by not having 

 specimens of the type species of numerous genera, and this has 

 resulted, for them as for me, in unsatisfactory definitions of some of 

 the genera. In general, these authors have recognized as valid 

 several genera that I have placed as synonyms of other genera, and 

 they name one new genus, Kumococius, with Insidiator detrusus 

 Jordan and Scale as the type species. In my key, Kumococius traces 

 down to Thysanophrys. 



Matsubara and Ochiai illustrate the "iris lappet," otherwise known 

 as the umbraculum, as being different in each of the eight genera 

 recognized, but very similar for each species in each genus. It is 

 very similar in all the three species of Thysanophrys herein described. 

 This organ has the ability to expand and contract, much like the 

 iris of our eyes. The umbraculum appears to be used as a sun shade 

 to be adjusted as required in the bright light and sandy habitat 

 where flatheads live. 



