﻿SIX 
  SUBFAMILIES 
  OF 
  ATHERINIDAE 
  — 
  SCHULTZ 
  31 
  

  

  The 
  genus 
  Chirostoma 
  appears 
  to 
  be 
  related 
  to 
  Menidia, 
  and 
  such 
  

   species 
  as 
  Chirostoma 
  jordani 
  are 
  difficult 
  to 
  separate 
  from 
  Menidia, 
  

   generically. 
  

  

  The 
  generic 
  diagnosis 
  in 
  the 
  key 
  is 
  based 
  on 
  a 
  large 
  number 
  of 
  speci- 
  

   mens 
  of 
  Chirostoma 
  humboldtiana 
  and 
  numerous 
  other 
  species 
  refer- 
  

   able 
  to 
  Chirostoma 
  from 
  Mexico. 
  

  

  The 
  following 
  types 
  and 
  paratypes 
  of 
  the 
  species 
  listed 
  below 
  have 
  

   been 
  examined 
  : 
  

  

  Chirostoma 
  attenuatum 
  Meek, 
  paratypes, 
  U. 
  S. 
  N. 
  M. 
  No. 
  55782. 
  

  

  Chirostatna 
  promelas 
  Jordan 
  and 
  Snydee, 
  para 
  type, 
  U. 
  S. 
  N. 
  M. 
  No. 
  61274. 
  

  

  Chirostoma 
  zirahuen 
  Meek, 
  paratype, 
  U. 
  S. 
  N. 
  M. 
  No. 
  55780. 
  

  

  Chirostoma 
  jordani 
  Woolman, 
  type, 
  U. 
  S. 
  N. 
  M. 
  No. 
  45572, 
  paratypes, 
  U. 
  S. 
  N. 
  M. 
  

  

  Nos. 
  37830, 
  47509, 
  125441. 
  

   Chirostoma 
  hartoni 
  Jordan 
  and 
  Evermann, 
  type, 
  U. 
  S. 
  N. 
  M. 
  No. 
  23136. 
  

   Chirostoma 
  estor 
  Jordan, 
  type, 
  U. 
  S. 
  N. 
  M. 
  No. 
  23124. 
  

  

  Dr. 
  F. 
  De 
  Buen 
  (Ann. 
  Inst. 
  Biol. 
  Mex., 
  vol. 
  16, 
  No. 
  2, 
  pp. 
  499-530, 
  

   1945) 
  has 
  recognized 
  certain 
  genera 
  and 
  subgenera 
  in 
  his 
  recent 
  studies 
  

   of 
  Mexican 
  silversides. 
  He 
  has 
  given 
  full 
  generic 
  rank 
  to 
  Elopsarum, 
  

   with 
  the 
  following 
  subgenera: 
  Elopsarum 
  Jordan 
  and 
  Evermann, 
  

   including 
  E. 
  arge 
  Jordan 
  and 
  Snyder, 
  E. 
  lalarcae 
  (Meek) 
  , 
  E. 
  jordani 
  

   jordani 
  (Woolman), 
  and 
  E. 
  j. 
  mezquital 
  (Meek) 
  ; 
  Charalia 
  De 
  Buen, 
  

   including 
  E. 
  regani 
  (Jordan 
  and 
  Hubbs) 
  , 
  E. 
  hartoni 
  charari 
  De 
  Buen, 
  

   E. 
  hartoni 
  hartoni 
  (Jordan 
  and 
  Evermann) 
  , 
  and 
  E. 
  hartoni 
  zirahuen 
  

   (Meek). 
  Under 
  the 
  genus 
  Chirostoma 
  Swainson, 
  De 
  Buen 
  (p. 
  510) 
  

   recognizes 
  the 
  following 
  subgenera 
  : 
  Palmichthys 
  De 
  Buen, 
  including 
  

   only 
  the 
  genotype, 
  Chirostoma 
  diazi 
  Jordan 
  and 
  Snyder; 
  

   Ocotlanichthys 
  De 
  Buen, 
  including 
  only 
  Chirostoma 
  sphyraenu 
  Boul- 
  

   enger, 
  the 
  genotype. 
  

  

  Lethostole 
  Jordan 
  and 
  Evermann 
  has 
  the 
  following 
  species 
  or 
  sub- 
  

   species 
  referred 
  to 
  it 
  by 
  De 
  Buen 
  ( 
  1945, 
  pp. 
  521-522) 
  : 
  Chirostoma 
  estor 
  

   estor 
  Jordan, 
  C. 
  estor 
  pacanda 
  De 
  Buen, 
  and 
  C. 
  estor 
  copandaro 
  De 
  

   Buen. 
  

  

  Chirostoma 
  Swainson 
  has 
  the 
  following 
  species 
  referred 
  to 
  this 
  sub- 
  

   genus 
  by 
  De 
  Buen 
  (1945, 
  pp. 
  511-512) 
  : 
  Chirostoma 
  humholdtianum 
  

   (Cuvier 
  and 
  Valenciennes), 
  C. 
  chapalae 
  Jordan 
  and 
  Snyder, 
  C. 
  com- 
  

   pressimi 
  De 
  Buen, 
  C. 
  grandocule 
  (Steindachner) 
  , 
  C. 
  consocium 
  Jordan 
  

   and 
  Hubbs, 
  C. 
  ocotlanae 
  Jordan 
  and 
  Snyder, 
  and 
  C. 
  lucius 
  Boulenger. 
  

  

  De 
  Buen 
  recognizes 
  as 
  a 
  full 
  genus 
  Otalia 
  De 
  Buen, 
  referring 
  but 
  

   one 
  species, 
  Chirostoma 
  promelas 
  Jordan 
  and 
  Snyder, 
  the 
  genotype, 
  

   to 
  it. 
  

  

  Since 
  the 
  morphological 
  characters 
  of 
  these 
  genera 
  and 
  subgenera 
  

   overlap 
  considerably, 
  I 
  am 
  inclined 
  to 
  recognize 
  but 
  one 
  genus, 
  Chiros- 
  

   toma^ 
  and 
  would 
  prefer, 
  at 
  present, 
  to 
  consider 
  those 
  proposed 
  by 
  De 
  

   Buen 
  at 
  most 
  of 
  no 
  higher 
  rank 
  than 
  subgenera. 
  Since 
  no 
  full 
  com- 
  

  

  