Fig. 14:57. Ephydridae larvae, a-c, Parydra pusilla (Mg.): a, 

 dorsal view; fa, anterior spiracle; c, oblique view of head region 

 showing mouth hooks (ant, antenna; mx, maxillary palpus). d,f,g, 

 He/oeomyi'a petro/ei (Coq.), larva: d, pharyngeal skeleton; f, 

 diagram of posterior spiracle in longitudinal section; g, posterior 

 spiracle, e, Ephydra riparia Fall., posterior spiracle as in i (o-c, 

 Nielsen, eta/., 1954; d-g, Thorpe, 1930). 



counties aldrichi Sturtevant and Wheeler 1954 



— Clypeus visible in profile, gradually tapering in width, 

 narrowing posteriorly; wings hyaline, sometimes with 

 dark spots at apices of veins or on cross veins or dark 

 with pale spots 2 



2. Head bristles small and thin, ocellars less than 1/2 

 as long as the distance between their bases to anterior 

 margin of front; 2nd costal section more than twice as 

 long as 3rd (subgenus Parydra Stenhammar) 3 



— Head bristles larger, ocellars more than 1/2 as long 

 as distance from their bases to anterior margin of front; 

 2nd costal section less than twice as long as 3rd 

 (subgenus Chaetoapnaea Hendel) 5 



3. Postscutellum bare and shining in middle; apical 

 tubercles small and globose; northern California 



bituberculata nitida Cresson 1915 



— Postscutellum entirely opaque pruinose 4 



4. Tibiae mostly reddish; apical scutellar tubercles small 

 and globose; southern California 



tibialis Cresson 1916 



— Tibiae entirely black; apical scutellar tubercles large, 

 about twice as long as broad; northern California 

 incommoda Cresson 1930 



5. Face strongly convex, a prominent median hump high on 

 face, the face vertical below 6 



— Face straight or oblique, prominent at epistoma; frontal 

 bristles long 7 



Fig. 14:58. Brachydeutera argentata (Walk.), a, larval pharyn- 

 geal skeleton; c, larva, lateral view; fa, puparium, lateral view 

 (Johannsen, 1935). 



471 

 Wirth and Stone: Diptera 



6. Second costal section more than 1.5 times as long as 

 3rd; wing dark with extensive clouds over cross veins; 

 California, common aurata Jones 1906 



— Second costal section scarcely longer than 3rd; winy 

 clear with light clouds over cross veins; California 



breviceps vicina Cresson 1940 



7. Marginal cell broader than submarginal at the anterior 

 cross vein; head noticeably broader than high; tarsi 

 pale; Humboldt County borealis (Cresson) 1949 



— Marginal cell not noticeably broad 8 



8. Second vein acutely entering costa, rarely with an 

 appendage; northern California. ... paullula Loew 1862 



— Second vein long, paralleling costa and more or less 

 abruptly entering it, generally with an apical cloud 

 and appendage 9 



9. Wings much wrinkled, with 4 or 5 small, round white 

 spots at the cross veins; prominent, small, round white 

 spot at mesal sutural angles of mesonotum; scutellum 

 elongate, very convex and acute apicad; Humboldt and 

 San Mateo counties varia Loew 1863 



— Wings not conspicuously wrinkled; white spots or 

 areas at cross veins large, not conspicuous 10 



10. Face opaque brown; halteres and tarsi pale; common 

 in California appendiculata Loew 1878 



— Face more or less shining, not opaque, overcast with 

 brown or white , 11 



11. Halteres and tarsi pale; scutellum rather narrow apicad 

 and generally with a small apical tubercle; California 

 socia (Cresson) 1934 



— Halteres and tarsi brown; scutellum broadly rounded 

 at apex; Mono County halteralis (Cresson) 1930 



Tribe HYADININI 



Genus Ochthera Latreille 



Both adults and larvae of Ochthera are predaceous on 

 smaller insects. The adults are very common along 

 marshy stream margins and are easily recognized by 

 their strikingly enlarged fore femora and spurred fore 

 tibiae which are held mantislike (fig. 14:55n). The 

 larvae of Ochthera pilimana Becker from Java which 

 were described by Hennig (1943) have untoothed 

 mandibles fitting their predaceous habits, unique 

 among this family. 



Key to Adults of the California Species of Ochthera 



1. Face broad, as broad at level of tubercle as height, 

 uniformly brassy; palpi and fore tarsi black; fore 

 tibial spur 1/3 as long as tibia; California 



mantis (Degeer) 1776 



— Face narrow, twice as high as broad; palpi and fore 

 tarsi yellowish; fore tibial spur 1/2 as long as tibia 



2 



2. Face with median, shining, black spot above the 

 tubercle; femora black; all tarsi reddish yellow; San 

 Diego to San Bernardino counties 



cuprilineata Wheeler 1896 



— Face uniformly grayish; fore- and mid-femora yellowish 

 brown; hind tarsi black; Riverside County 



melanderi Cresson 1944 



Key to Adults of the California Species of 



Pelina 



1. Face higher than broad; head not twice as broad as 



