The Crane-Flies of New York — Part II 907 



Genus Rhaphidolabis Osten Sackon {Gr. needle + forceps) 



1869 Rhnphidolahh 0. S. Mon. Dint. N. Amer., part 4, p. 2Sl:-2'7. 

 1911 Claduroides Brun. Rec. Indian Mus., vol. (J, p. 288. 



Rhaphidolabis is a small genus, including about fifteen described species 

 ranging thruout the North Temperate Zone. The larvae strongly resemble 

 those of Dicranota, and the two genera are undoubtedly very closely 

 related. 



Rhaphidolabis tenuipes O. S. 



1869 Rhaphidolabis tenuipes O. S. Mon. Dipt. N. Amer., part 4, p. 287. 



Needham (1908 a: 212-214) found adult flies of the species Rhaphidolabis 

 tenuipes in great numbers in tent traps set over Beaver Meadow Brook 

 in the Adirondacks in July and August, 1907. Larvae that almost cer- 

 tainly belong here were found among the rounded stones in the creek 

 bottom. 



Larva. — Length excluding caudal lobes, 8-9 mm. 

 Length of caudal lobes, 1 mm. 



Abdominal segments 3 to 7 with prominent fleshy prolongations on ventral surface, these 

 being retractile, unpaired, and widely separated on mid-ventral line, and bearing at tip a 

 circlet of outcurved booklets, with series of smaller booklets beyond. Spiracular disk with 

 the two ventral lobes long and obtuse at tips. (Further details are given by Needham.) 



Rhaphidolabis cayuga Alex, (supposition) 



1916 Rhaphidolabis cayuga Alex. Proc. Acad. Nat. Sci. Phila., p. 543-544. 



Larvae which the writer refers to this species were found in Needham's 

 Glen, Ithaca, New York, on March 30, 1916. Later in the season, in 

 April and May, adult fli(;s of the species arc very numerous in this glen, 

 and these account for the specific reference. 



Larva.- — Agreeing very closely with descriptions of both Dicranota and Rhaphidolabis 

 tenuipes. Spiracles large, lying in a distinct longitudinal groove, by the closing of which they 

 are capable of being entirely hidden. Antenna long and slender, tapering to apex, which 

 bear; numerous short papillae. Mandible with third lateral tooth of ventral cutting 

 row very long and acute, much exceeding second tooth; basal tooth shaped like a prun- 

 ing knife, with the cutting edge sinuate; at prosthecal region of mandible, a small tuft of 

 about seven or eight long setae. IMa.xilla having the two lobes firmly united except on 

 apical quarter. 



