REVISION OF MOTHS OF PRODOXINAE 47 



thulei Staudinger, occurs to the north in the Shetland Isles, and the 

 typical form is restricted further south to the British mainland. 



The forewmg measurements of female Tegeticula maculata are as 

 follows (see p. 10 for explanation of symbols) : 



N 

 T. maculata maculata 30 



T. maculata extranea 30 



Several botanists (e.g., Trelease, 1893; Hames, 1941; McKelvey, 

 1947; Webber, 1953) have recognized the existence of two or more 

 subspecies or forms of Yucca whipplei in southern Cahfornia. Opin- 

 ions vary as to how many entities are involved and to the respective 

 characteristics of each. Vegetative featm-es, particularly growth 

 habits, usually are rehed upon for distmction, as well as differences in 

 distribution. It is believed that precise distributional and host 

 records for the subspecies of Tegeticula maculata \viU show correlations 

 in regard to the relationships of the various forms of Yucca whipplei. 

 Conversely, additional studies on the systematics of the host should 

 furnish valuable information on the moths. For example, after 

 reviewing the taxonomy of Y. whipplei, McKelvey (1947, p. 45) 

 predicted that "with time, one or more floral characters will be found 

 to distinguish two races which even now appear to be geographically 

 separated as far as habit of growth, of itself an important character, 

 is concerned." The knowTi distributions of the subspecies of T. 

 maculata strongly support McKelvey's supposition in that evidence 

 is beginning to show that the two moths are restricted to two distinct 

 biotypes of Y. whipplei, one of which is more northern in its distribu- 

 tion than the other. Haines (1941) recognized five subspecies of 

 Y. whipplei and discussed their ranges in some detail. The status of 

 a few of his subspecies appears doubtful; however, from his key of 

 the various forms it is possible to recognize two distinct groups of 

 Y. whipplei. One group is characterized by those plants which 

 produce sohtary rosettes and die after fruitmg. Under this couplet 

 in his key, Haines included the two subspecies typica and parishii. 

 The other major group included the subspecies caespitosa, intermedia, 

 and percursa. These plants are characteristic in that they are 

 perennial and produce numerous rosettes; thus, in these individuals 

 only the flower stalk dies after fruiting. Although these fundamental 

 differences were not given special emphasis by Haines, they undoubt- 

 edly represent an important division within Y. whipplei. This is 

 suggested fm-ther by the apparent association of the two subspecies 

 of r. maculata. As illustrated in maps 4 and 5, the subspecies 

 maculata is apparently sympatric with the "caespitosa" group of Y. 



