Drosophila mojavensis wrigleyi Castrezana, 2009

Pfeiler, E., Castrezana, S., Reed, L. K. & Markow, T. A., 2009, Genetic, ecological and morphological differences among populations of the cactophilic Drosophila mojavensis from southwestern USA and northwestern Mexico, with descriptions of two new subspecies, Journal of Natural History 43 (15 - 16), pp. 923-938 : 935-936

Drosophila mojavensis wrigleyi Castrezana , new subspecies

( Figure 3D )

Drosophila mojavensis mojavensis Ruiz, Heed and Wasserman, 1990

Type material

Holotype. Male: California ( USA), Santa Catalina Island, 20 October 2007, V. Carlin-Harris, deposited at the San Diego Drosophila Stock Center collection at the University of California, San Diego, La Jolla, California (acquisition no. 483 from collection CI 1007). Paratypes (same collection data as holotype): 15 males and 15 females deposited at the San Diego Drosophila Stock Center collection (acquisition nos. 484–498 (males) and 499–513 (females)); 10 males and 10 females deposited at the Smithsonian Diptera Collection, United States National Museum of Natural History ( NMNH), Washington, DC.

Diagnosis

Drosophila m. wrigleyi can be distinguished from the other subspecies by the shape of the aedeagus ( Figure 3D ). Internal margin of aedeagus/external margin of aedeagal apodeme index51.37 (1.35–1.49; n 515); ventral margin of aedeagus/wide aedeagal apodeme index53.97 (3.47–4.27). Ventral margin of aedeagus is almost straight; anterior dorsal margin has a slight depressive curve with small protuberances appearing like a saw with two teeth.

Distribution and host cactus

Currently known only from Santa Catalina Island off the coast of southern California, USA ( Figure 1 ). Host cactus: prickly-pear ( Opuntia spp. , including O. littoralis ).

Remarks

Fasolo and Krebs (2004) found that D. m. wrigleyi showed significantly greater thermal tolerance than both D. m. sonorensis from southern Arizona (Santa Rosa Mountains) and San Carlos, Sonora, and D. m. baja from Baja California Sur (Ensenada de los Muertos). Fasolo and Krebs (2004) also noted that preliminary mtDNA studies using 16 S rRNA showed D. m. wrigleyi possessed three apparently unique base substitutions compared to flies here assigned to D. m. baja and D. m. sonorensis.

Material examined

External measurements were conducted on 20 males and 20 females from collection CI 1007; internal (genitalia) measurements were conducted on 15 males.

Etymology

Subspecies name suggested by Hocutt (2000) in honor of the Wrigley family, and especially William Wrigley, Jr., for their efforts in protecting Santa Catalina Island.

Figures

Figure 1. Map showing approximate geographic distribution of the four subspecies of Drosophila mojavensis in southwestern USA and northwestern Mexico.?5unconfirmed subspecies at San Felipe, Baja California. Numbers show localities where flies used for laboratory cultures were collected: (1) Mojave; (2) Baja; (3) Sonora; (4) Catalina (see ‘Materials and methods’ for details).

Figure 3. Photographs showing lateral views of the aedeagus and aedeagal apodeme in the four subspecies of Drosophila mojavensis. (A) D. m. mojavensis; (B) D. m. baja; (C) D. m. sonorensis; (D) D. m. wrigleyi.