major Hine 1901. 

 mariposa James 1939. 

 niger Bigot 1879. 

 pardalinus James 1936. 

 tahoensis Coquillett 1902. 



441 



Wirth and Stone: Diptera 



Lake, Santa Clara Lassen National Park. Other descriptions of larvae 

 MarlposaCounty of fcig ^nus may ^ found in Mal | 0( . h (1917) an ,| 



Invo County J onan n sen (1922). The following key to the California 

 Lake Tahoe species has been adapted from James and Stoyskal 

 (1952): 



Genus Adoxomyia Kerte*sz (Clitellaria of authors) 



It is probable that this genus may have aquatic habits, 

 but the only information available on the breeding 

 habits consists of two specimens in the National 

 Museum, of claripennis James .from Pima County, 

 Arizona, which were reared by R. E. Ryckman from 

 decomposing cactus. The following key to the Cali- 

 fornia species is adapted from a recent revision of 

 the genus by James (1943). 



Key to Adults of the California Species of Adoxomyia 



1. Legs, including tarsi, wholly black, or black except 

 for the knees 2 



— Tarsi pale in large part, and contrasting with the black 

 tibiae; California argentata (Williston) 1885 



2. Antennal flagellum red, at least on the basal seg- 

 ments (fig. 14:44^) 3 



— Antennal flagellum entirely black; northwestern and 

 central California rustica (Osten Sacken) 1877 



3. Pleura predominantly black-pilose; mesonotum of male 

 with abundant, erect black pile; venter black-pilose 

 (reddish-brown, in certain lights) on the basal seg- 

 ments; northern and central California 



lata (Loew) 1872 



— Thorax entirely pale-pilose; pile of mesonotum, in 

 both sexes, appressed; venter entirely pale-pilose; 

 southern California .... appressa appressa James 1935 



Subfamily STRATIOMYINAE 



Genus Myxosargus Brauer 



According to James (1942) who revised this group, 

 Myxosargus belongs in a distinct tribe of the Stratio- 

 myinae together with several other small genera, the 

 habits of none of which are known. It is entirely pos- 

 sible that they may not be aquatic. 

 California species: 



knowltoni Curran 1929. 



Inyo, Los Angeles 



Genus Stratiomys Geoffroy 



The larvae of Stratiomys are among the largest of the 

 family and are recognized by their fusiform shape and 

 the long, tapering caudal air tube (fig. 14:45e). There 

 are no transverse rows of long body hairs or ventral 

 hooks on the next to the last segment. They may breed 

 in a wide variety of aquatic habitats from ponds and 

 streams to saline pools and hot springs. Needham 

 and Christenson found S. melastoma Loew breeding 

 in shallow, slow-flowing water in Logan River, Utah. 

 Brues (1928) described the larvae of two unnamed 

 species of Stratiomys from hot springs in Mount 



Key to Adults of the California Species of Stratiomys 



1. Antenna short, the 1st segment normally not more than 

 3 times as long as the 2nd, the flagellum at least 2 

 times as long as the 1st segment; abdomen flattened, 

 the venter either entirely yellow or with black basal 

 bands or spots 2 



— Antenna longer, the 1st segment normally 4 or more 

 times as long as the 2nd, the flagellum less than 

 2 times as long as the 1st segment; venter partly or 

 wholly black 3 



2. Abdominal sternites each with a black basal band; 

 male with eyes usually distinctly hairy; both sexes 

 with femora, except extreme apices, black, only in 

 rare cases brown, but still darker than the tibiae; 

 Sierra Nevada laticeps Loew 1866 



— Abdominal sternites wholly pale or with narrow basal 

 spots or bands; eyes in both sexes bare; female with 

 femora yellow, at base, apex, in part black, male with 

 femora black except apical 4th or more; California 



currani James 1932 



3. Fourth abdominal tergite with an oblique black mark 

 interrupting lateral yellow spots on each side (fig. 

 14:446); eyes hairy in both sexes; widespread in 

 California maculosa Loew 1866 



— Fourth abdominal tergite not so colored; eyes bare in 

 both sexes 4 



4. Posterior orbit broader below than above and broadly 

 yellow at least in its lower part; in the female yellow 

 throughout or at most black in its upper 4th, bare except 

 for short, inconspicuous hairs, and broad throughout, 

 its minimum breadth at least equal to length of 2nd 

 antennal segment; in the male distinctly broadened in 

 the lower part; facial orbits broadly yellow (except in 

 some high altitude males of S. barbata); sternites with 

 posterior yellow part approximately equally developed 

 on all segments, or at most only slightly more so on 

 the anterior segments 5 



— Posterior orbit not much broader in lower part, narrow 

 throughout in the male, relatively so in the female, its 

 minimum breadth usually distinctly less than length 

 of 2nd antennal segment; yellow color of posterior 

 orbit usually narrow or lacking; if posterior orbit is 

 relatively wide or somewhat broadened and yellow on 

 lower half or more, it is clothed in part with conspic- 

 uous tomentum and the posterior yellow portion of the 

 sternites is definitely more strongly developed on the 

 anterior than on the posterior segments 6 



5. Each sternite usually at least half black, the black 

 part forming a parallel-sided anterior transverse band; 

 posterior pale part of 4th tergite usually interrupted 

 medianly; pale marking of 5th tergite consisting of a 

 median triangle which is widest posteriorly; femora, 

 except knees, black; face of male usually largely 

 black, usually with black pile; California 



barbata Loew 1865 



— Sternites usually predominantly yellow, each with a 

 black anterior transverse band which is broadest in the 

 middle; posterior pale part of 4th tergite continuous, 

 rarely narrowly interrupted, but when so without an 

 isolated median triangle; pale marking- of 5th tergite 

 a conspicuous median pentagonal marking which is 

 usually distinctly broader anteriorly; face pale, oral 

 margin black; Sierra Nevada melastoma Loew 1865 



6. Predominantly black species, the abdominal tergites 

 wholly black except occasionally traces of yellow 

 markings on the median line of the 5th segment, and 

 laterally or at the anterior corners of the 2nd segment, 

 the ventrites also black except for narrow posterior 



