154 MISC. PUBLICATION 631, U. S. DEPT. OF AGRICULTURE 



color. Length about 11-13 mm. Larva : No satisfactory distinguishing char- 

 acters can be given. 



Geographical Distribution. — Nearctic Region : This species was recorded 

 from Alaska, but the record was due to misidentification. Palaearctic Region: 

 Iceland, Faeroes, Ireland, Scotland, Wales, England, Spain, France, Netherlands, 

 Switzerland, Italy, Sicily, Norway, Sweden, Finland, Lapland (Swedish), Den- 

 mark. Germany, Czechoslovakia, Austria, European Russia (northward to 

 Arkhangelsk), Madeira. 



Pathogenesis. — This species has been accused of producing intes- 

 tinal myiasis, although the determination was made from the larva 

 alone and is quite probably erroneous. Chevrel (27, p. 377) cites a 

 supposed case of urinary myiasis, which he considers probably due 

 to the subsequent entrance of the larva into the vessel containing the 

 urine. 



The Family EPHYDRIDAE 



These are the shore flies which are often abundant in moist places. 

 Only one genus has been reported as involved in myiasis. 



The Genus TEICHOMYZA Maequart 



The name of this genus has been emended to Tichomyza, but it is 

 better to follow T the original spelling. 



The genus is known to occur definitely only in Europe and western 

 South America. It may be distinguished from the other European 

 genera of Ephydridae by the following combination of characters : 

 The eyes are bare. The second antennal segment has only the ordinary 

 hairs above, without the crooked apical spine characteristic of many 

 members of this family ; the arista is bare. The oral opening is large ;. 

 the face is prominent and convex, clothed with scattered hairs, and 

 with a row of strong dowmwardly directed bristles along the oral 

 margin and a row of bristles on each side of the facial prominence. 

 The clypeus is small, usually not extending below the oral margin. 

 There are two pairs of dorsocentral bristles, which are postsutural, 

 and one of acrosticals. which are presutural ; there are 3 pairs of 

 lateroscutellars. The wings are uniformly infuscated; the costa 

 reaches vein m 1+2 . Only one species has been described. 



TEICHOMYZA FUSCA Maequart 



Recognition Characters. — Adult : This is a brownish-black species, about 

 4 mm. in length. Larva (fig. 92) : The mature larva is 10-13 mm. in length, 

 cylindrico-fusiform, translucent, and covered with small blackish setulae. Each 

 of the thoracic segments beyond the first and abdominal segments anterior to the 

 seventh bears an ambulatory protuberance (proleg) on each side, near the middle ; 

 each anterior spiracle ends in about 18 digitate processes ; the posterior spiracles 

 are on long stalks projecting backward ; the mouth hooks are toothed below. 



Geographical Distribution. — Palaearctic Region: All Europe (according to 

 Becker), Ireland, England, France, Netherlands, Italy, Germany, Czechoslovakia, 

 Bulgaria, European Russia. Neotropical Region : Chile ; also on shipboard 

 off the coast of Peru. 



Biology and Pathogenesis. — The larvae are frequently found in 

 outdoor urinals and excrement; they breed in wet places, but not in 

 deep urine or water. Numerous cases of urinary myiasis have been 

 recorded. Chevrel (27) discusses three of these in detail, and though 

 evidence points toward their authenticity, he leaves them in a question- 

 able status, as did the physician who reported them. Since details of 



