Genera of Paralepididae — HARRY 
243 
Fig. 21. Genotype of Sudis (S. hyalina Rafinesque, from off Madeira, 315 mm. in standard length). 
Paralepis (in part) Cocco, 1839: 49; Cams, 
1893: 566; Sanzo, 1917: 1. 
Siidis (in part) Parr, 1928: 34. 
DIAGNOSIS: Body compressed and elongate. 
Ventral carina on belly moderately developed. 
Head large, strongly compressed. Snout very 
large and deep. No nonossified prolongations 
on tip of lower jaw. Nostrils situated almost 
0.33 length of maxillary before posterior tip 
of maxillary. Eye very large. Pupil vertically 
oval, much larger than lens. Supramaxillary 
large, more than 0.5 as long as maxillary, 
splinter-like, closely bound to maxillary. 
Teeth on lower jaw very large, in 1 or 2 series, 
of triangular shape and strongly compressed; 
edges minutely serrate. Few mandibular teeth 
depressible. Teeth on premaxillary minute, 
serrate, all fixed. Teeth on palatines moderate- 
ly reduced, all fixed; anterior teeth in 2 rows 
with long teeth sometimes accompanied by 
short ones; anterior double series followed by 
single series of short or minute teeth. Tongue 
large, moderately far forward in mouth. Gill- 
rakers tiny, spinous; each raker composed of 
2-4 short teeth in single row; rakers not ex- 
tending forward beyond angle of gape. Pha- 
ryngobranchial teeth well developed in single 
patch on each side. 
True scales developed on preoperculum in 
2 series. Otherwise body and head scaleless. 
The lateral-line tube covered by single row 
of distinct, overlapping, scale-like segments 
lacking all trace of circuli or annuli. Each 
segment pierced by 5-8 pores above and be- 
low near upper and lower margins. Dorsal fin 
with 14-16 rays. Vertebrae 59, as far as known. 
FOSSIL HISTORY 
The order Iniomi first appeared in the Cre- 
taceous, in which the recent families Aulopo- 
didae, Chlorophthalmidae, Myctophidae, and 
probably Bathypteroidae are clearly evident. 
The suborder Alepisauroidea ( = Paralepidoi- 
dea Gill, 1893) appears to be represented in 
the Cretaceous by the family Ichthyotringidae 
(new family name to replace Rhinellidae Jor- 
dan, 1905, because the monotypic genus 
Rhinellus Agassiz, 1844, is preoccupied; Ich- 
thyotringa Cope, 1878, is the next name avail- 
able), and perhaps the Dercetidae also belong 
here. Ichthyotringa resembles a Stidis with an 
especially prolonged snout. The exact extent 
of relationships are obscure, however, because 
the head bones are inadequately known. The 
Dercetidae, containing perhaps six genera (see 
the list by Romer, 1945: 584), look remark- 
Fig. 22. Genotype of Sudis (S. hyalina Rafinesque, 
from off Madeira, 315 mm. in standard length). A, an- 
terior part of snout; B, enlarged section of teeth on 
middle of premaxillary; C, anterior lateral-line segments; 
D, gillrakers on first arch; E, dorsal surface of tongue. 
(See explanation of morphological figures in text.) 
