Bioacoustics of Ammopelmatus lightfooti

Figs 572–581 , Tables 32 , 39 Distribution. ( Fig. 572 ). Only known from the sand dunes around Alvord Lake, Harney Co., in southeastern Oregon . Recognition characters. Member of Lightfooti Group. Medium sized, light colored, sand obligate taxon with a calling song of 3–3.2 drums/s, usually 3 outer rear leg tibial spines, and 2n ♂ =23. Most closely related to three other Lightfooti Group taxa: The more northern A. juniperdunes has a faster calling drum, 2n ♂ =21, and 4 outer rear leg tibial spines; the more eastern A. idaho has 2n ♂ =19; while the more western A. christmasvalleydunes has a slightly faster calling drum, 2n ♂ =19, and 4 or 5 outer rear leg tibial spines. Holotype : Adult male (in alcohol, Fig. 573 ): Oregon , Harney Co ., Alvord Lake Dunes , on dirt road between 42.618767° -118.380967° and 42.598283° -118.377333°, 1220m , 13-vi-2004 (S04-45), DBW and DC Lightfoot. R 04-11. Molt to adult 29-vii-2004 . Deposited CAS , Entomology type #20089. Measurements in mm: Body length 31.35, hind femur length 10.31, hind femur width 3.65. Fore leg tibia with 2 ventral spurs; middle leg tibia with 8 calcars, 2 ventral spurs; hind leg tibia ( Fig. 574 ) with 5 and 6 inner and 3 and 4 outer spines, 2 ventral spurs. Allotype : Adult female (in alcohol, Fig. 575 ): same data as holotype except R04-23. Molt to adult 25-viii-2004 . Deposited CAS , Entomology #9079348. Measurements in mm: Body length 32.15, hind femur length 8.96, hind femur width 3.37. Fore leg tibia with 3 ventral spurs; middle leg tibia with 8 calcars, 2 ventral spurs; hind leg tibia ( Fig. 576 ) with 4 and 5 inner and 3 outer spines, 2 ventral spurs. Ovipositor Fig. 577 . Paratypes . ♂ 4 ♀ 25. OREGON , Harney Co ., all individuals collected over a 2.6 km stretch of road as specified above under holotype . 10-viii-1983 (S83-109) DC Lightfoot ♀ 4; 14-ix-1998 (S98-91A) ♀ 4; 5-ix-1999 (S99-102) ♀ 8; 15-vi-2001 (S01-56) ♂ 1; 13-vi-2004 (S04-45) ♂ 2 ♀ 3; 25-vi-2014 (S14-27) ♂ 1 ♀ 6. Drum. Male and female calling drums similar except males with a sex clarification drum ( SCD ). Male : Holotype R04-11 ( Fig. 578 ) had 14 SCDs (to finger drumming) at a rate of ~12.5 drums/s, and then 1 calling drum ( Fig. 579 ) of 31 single drums over 10.0s (3.1 drums/s) at 21° C. Longest SCD was 22 drums in 1.74s (12.6 drums/s). Female : Allotype R04-23 ( Fig. 580 ) had 46 single drums over 14.6s (3.2 drums/s) at 20°C . Derivation of name. Named after David C. Lightfoot, who discovered this species, and also in appreciation for his many years of field companionship and collegiality. Habitat. Over the years, we have laid various oatmeal trails over a 2.6 km stretch of sandy road between northern site 42.618767° -118.380967°, 1230m ; and southern site 42.598283° -118.377333°, 1227m . Collected individuals always associated with sand, but results variable. For instance, on 5-ix-1999 (S99-102), we got 8 adult females at an oatmeal trail on large dunes and none collected elsewhere. In other years, we were most successful in getting late instars, earlier in the season, in areas with just a minimal depth of sand while having no or little success on large dunes. Perhaps mated adult females move to large dunes for oviposition since they probably oviposit deep in the sand? Life cycle and seasonal occurrence. On 5-ix-1999 (S99-102) we collected 8 adult females. On 13-vi-2004 (S04- 45), we collected 2 adult males and 4 adult females, 1 mid-late instar male and female, and 1 mid instar female. On 25-vi-2014 (S14-27), we collected 1 late instar male and 5 late instar females and 1 mid instar female. Variation. For 31 individuals, 10 had 2 and 20 had 3 fore leg tibial ventral spurs; 29 had 8 middle leg calcars and 2 ventral spurs; and for 31 specimens , 3 had 4, 26 had 5, and 2 had 6 hind leg inner spines, while 28 had 3 and 3 had 4 outer spines, all with 2 ventral spurs. DNA . Fig. 496 , p. 304 ). Type locality F1160 (S01-56) and F2413 (S14-27) recovered in Group 8 Lightfooti; and most closely related to other Lightfooti Group taxa A. christmasvalleydunes (2n ♂ =19) and A. juniperdunes (2n ♂ =21), while A. lightfooti has 2n ♂ =23. Karyotype. 2n ♂ =23. One type locality male checked: T01-48 ( Fig. 581 , S01-56) with 8 metacentric or submetacentric autosomal pairs; 3 acrocentric or telocentric autosomal pairs; and 1 metacentric X chromosome. Discussion. Near the most northern end of our 2.6 km long oatmeal trail transect, and not on sand, DC Lightfoot collected (S83-110, 10-viii-1983 ) one adult female of A. monolake ; while DBW and VF Lee collected (S98-91B, 14-ix-1998 ) an adult male of A. monolake in the same area, again off sand. Interestingly, only A. monolake has been found, and in moderate numbers, on nearby Crescent Dunes (S98-92), some 65 km due south of the Alvord Lake Dune area. More information on the Alvord Basin Sand Dune ecosystem can be found in Cobb et al. 1981 . The Alvord Dunes are part of the Lahontan Basin that also contains Blow Sand Mountain and Sand Mountain, Nevada ( Rahn & Rust 2000 ). Two species ( A. rusti and A. knighti ) in the Lightfooti Group of JCs occur at Blow Sand Mt, while one species (identity unknown since no adult males, drum, or DNA ) occurs at Sand Mt.