77 

 Scott; Aquatic Collembola 



at junction; length 1.5 mm.; cosmopolitan, found occa- 

 sionally on rain pools and stagnant water 



maritima Tullberg 1869 



Dentes and mucrones clearly articulated at junction . 2 

 Anal spines large; California, rain pools, standing 



water baconae Folsom 1916 



Anal spines small 3 



Mucrones with very broad lamellae or wings; unguiculus 

 present as small knob; color gray or violet, mottled; 



cosmopolitan, stagnant water welchi Folsom 1916 



Mucrones with narrow lamellae; unguiculus completely 

 absent; color dark blue; cosmopolitan, marshlands 

 bordering ponds humicola Tullberg 1876 



Genus Achorutes Templeton 1835 



One long tenent hair on tibiotarsus, not knobbed; anal 

 spines equal to length of hind claws (fig. 2:5); cosmo- 

 politan, stagnant water, fishponds, irrigation ditches 



armatus (Nicolet) 184 1 



Tenent hairs usually 3 to each tibiotarsus, clavate or 

 knobbed; anal spines about 1/5 as long as hind claws; 



cosmopolitan, stagnant water 



viaticus Tullberg 1872 



Genus Amirida Laboulbene 1865 



Color dark blue, eyes 5 on each side 2 



Color white, eyes absent; cosmopolitan, seashore 



granaria (Nicolet) 1847 



Postantennal organs with 6-10 peripheral tubercles in 

 a circle; 1 tenent hair on tibiotarsus; cosmopolitan, 



along seashore in intertidal zone 



maritima Guerin 1836 



Postantennal organs with 17-30 peripheral tubercles in 

 an irregular ellipse; no knobbed tenent hairs on tibio- 

 tarsus; cosmopolitan, along seashores on rocks and in 

 tidepools; inland in fish ponds and lake margins .... 

 tullbergi Schott 1891 



Family ISOTOMIDAE 



Key to the Genera 



Anus ventral, not terminal Folsomia Willem 1902 



Anus terminal 2 



Body with bothriotricha 3 



Body without bothriotricha .... Proisotoma Borner 1901 

 Hind femur with a thornlike process; manubrium without 

 ventral setae; mucrones tridentate, nonlamellate; tibio- 

 tarsus with a distal subsegment 



Archisotoma Linnaniemi 1912 



Hind femur without a thornlike process; manubrium with 

 many ventral setae; mucrones quadridentate, lamellate; 

 (fig. 2:4c) tibiotarsus without a distal subsegment 

 Isotomurus Borner 1903 



Genus Folsomia Willem 1902 



. Eyes absent; dentes with many dorsal crenulations; 



length 2 mm.; fish ponds, rain pools 



fimetaria Linneaus 1758 



Eyes present, 8 on each side; dentes with few dorsal 

 crenulations; on seashore under rocks in intertidal zone 

 elongata (MacGillivary) 1896 



Genus Proisotoma Borner 1901 



Two species have been reported from California, 

 P. aquae Bacon in stagnant water and rain pools, and 

 P. laguna Folsom in the intertidal zone along the 

 coast. 



Fig. 2:4. Diagnostic characters of Collembola. a, mucro of 

 Smynthurides aquaticus; b, mucro of Ptenothrix maculosa; c, 

 mucro of Isotomurus paluslris; d, mucro of Entomobrya sp.; e, 

 eye patch and ocelli of Entomobrya sp. 



Genus Isotomurus Borner 1903 



The only species found in California is /. palustris 

 (Muller) 1776 (fig. 2:4c). It is a cosmopolitan species 

 found on stagnant water. 



Genus Isotoma Bourlet 1839 



The one representative of this genus (fig. 2:3e) found 

 in California is /. besselsii Packard. It is found along 

 the seashore in the intertidal zone under rocks. 



Family E NTOMOB R Y ID A E 

 Key to the Genera 



1. Basal tooth of claw winged; clavate tenent hairs pres- 

 ent but weak Sinella Brook 1882 



— Basal tooth of claw not winged; clavate tenent hairs 

 well developed and strong (figs. 2:3#; 2:4d,e) 



Entomobrya Rondani 1861 



Genus Sinella Brook 1882 



A single cosmopolitan species, S. hoftii Schaeffer, 

 found on stagnant water, represents this genus. 



Genus Entomobrya Rondani 1861 



1. Color mottled dark brown with dark blue legs (fig. 2:1); 



California, seashore in intertidal zone 



laguna Bacon 1914 



— Color orange with a distinct dark blue saddle; legs 



pale; inland species on stagnant water, ponds 



atrocincta f. clitellaria Guthrie 1903 



Family SMYNTHURIDAE 

 Key to the Genera 



1. Exserted filaments of ventral tube not warty 2 



