
108 R. W. CROSSKEY 
realised the homonymy and published the replacement name Prodiaphania, which 
remains the valid name for this genus, and was used in publication by Malloch 
(1928) : 615; 1929 : 291) and Paramonov (1968 : 355, 384). Unfortunately, the 
name Senostoma Macquart has been misapplied to the genus, notably by Malloch 
(1936 : 10-15) and Townsend (1938 : 426), as the result of misidentification and 
erroneous synonymy of its type-species. Senostoma was described as a monotypic 
genus with S. variegata Macquart as its type-species, and Macquart’s female holotype 
of variegata from the Bigot collection is in the British Museum (Natural History) 
(Crosskey, I97I : 291); examination of this holotype shows that vaviegata (and 
therefore Senostoma) does not belong in the Rutiliini at all, but in the Prosenini 
near Rhynchiodexia Bigot (of which Senostoma may well be a senior synonym). 
Engel however found a female specimen in the collection of the Vienna Museum 
that belonged to the species Diaphania testacea Macquart (type-species of Diaphania 
= Prodiaphania) and bore a label erroneously purporting that it was Macquart’s 
type of variegata, and Engel (1925 : 344) therefore synonymised variegata with 
testacea; Townsend (1932 : 40) saw the same specimen in Vienna and also considered 
that this synonymy was correct, recording it again later in his Manual of Myiology 
(Townsend, 1938 : 426). It seems certain that neither Engel nor Townsend troubled 
to compare the Vienna specimen with Macquart’s (1847 : 96) original description of 
Senostoma variegata, from which it is obvious that it was not based on a Rutiliine 
specimen and that Macquart’s figure (plate 5, fig. 3) scarcely resembles a Prodiaphania 
species. Their mis-recognition of the type led Townsend (1938) to supplant his 
name Prodiaphania with Senostoma, which would be nomenclaturally correct if the 
synonymy of variegata and testacea was correct; as it is not, and as Senostoma as 
correctly interpreted is not a Rutiliine, the name Prodiaphania Townsend stands 
valid for the present genus. 
Prodiaphania is the most distinctive and easily recognized genus in the Rutiliini, 
and because of the external homogeneity of the species in conjunction with the 
presence of some unusual features can be more satisfactorily defined than the other 
genera. The palpi are minute (as Macquart noted in the original description of 
Diaphania) and this character alone separates Prodiaphania from all other genera, 
but other distinctive characters include the great enlargement of the upper calypter 
(which in the wings-closed position is as long as or nearly as long as the lower calyp- 
ter), the unusual elongation of the head in the epistomal axis (Text-fig. 7) with 
consequent elongation of the buccal opening (Text-fig. 15), the conspicuously plumose 
or unusually long-pubescent arista on which the hairing is strikingly bushy, and the 
exceptionally explanate costal base (Text-fig. 26) giving the impression of basal 
‘shoulders’ to the wings. Taken together these characters give Prodiaphania a very 
characteristic facies and set the genus rather apart from other genera; it is not 
possible to ascribe particularly close affinity to any other genus, but there is some 
notable resemblance is certain features such as the elongate buccal opening and 
explanate costal base to Formodexia gen. n. (but the very elongate palpi, normal 
upper calypter and haired postalar wall immediately distinguish Formodexia from 
Prodiaphania). The suprasquamal ridge is bare in Prodiaphania and this at once 
distinguishes the genus from Chrysopasta, Amphibolia and nearly all Rutilia, but the 
