Chanbria regalis Muma, 1951

Chanbria regalis Muma, 1951 View in CoL

( Figs 6A–F View Figure 6 , 7A–D View Figure 7 )

Chanbria rectus Muma, 1962 View in CoL , male holotype and immature female from Barstow , San Bernardino County County, CA, USA (AMNH). Image of type examined; new synonymy.

Chanbria tehachapianus Muma, 1962 View in CoL , male holotype from Tehachapi Mountains , Kern County, CA, USA (AMNH). Image of type examined; new synonymy.

Type material: Male holotype and one male paratype from Twentynine Palms, CA, USA. Female allotype from Palm Springs, CA, USA ( AMNH). Holotype examined.

Other material examined: México: Baja California: Ensenada: South of Punta Final , 29.743587°N, 114.292885°W, 25 April 2019, one ♂, H. Munillo; K. Munguia; E. Lopez, DMNS ( DMNS ZA.44237); GoogleMaps USA: Arizona: Pima Co.: South of Punta Final, 29.743587°N, 114.292885°W, 25 April 2019, one ♀, H. Munillo; K. Munguia; E. Lopez, DMNS ( DMNS ZA.44238); GoogleMaps Organ Pipe National Monument, 32.035706°N, 112.857283°W, 472 m, 23 May 1959, one ♂, K.E. Lucas, CAS ( CASENT 9033503); GoogleMaps California: Imperial Co.: near Ogilby, 32.814682°N, 114.841597°W, 545 m, 23 May 1959, three ♂, two ♀, V. Roth, CAS ( CASENT 9033512); GoogleMaps Salton Sea, 33.1872°N, 115.8376°W, July 2001, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16444); GoogleMaps Salton Sea, 33.1802°N, 115.8379°W, August 2001, one ♂, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16445); GoogleMaps Salton Sea, 33.1867°N, 115.8457°W, August 2001, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16447); GoogleMaps Salton Sea, 33.1974°N, 115.8374°W, 761 m, August 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16456); GoogleMaps Salton Sea, 33.1872°N, 115.8376°W, 763 m, April 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16457); GoogleMaps Salton Sea, 33.1868°N, 115.8431°W, 780 m, July 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16458); GoogleMaps Salton Sea, 33.1734°N, 115.84°W, 80 7m, July 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16459); GoogleMaps Salton Sea, 33.1734°N, 115.84°W, July 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16460); GoogleMaps Salton Sea, 33.1872°N, 115.8376°W, June 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16461); GoogleMaps Salton Sea, 33.1802°N, 115.8379°W, April 2002, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16462); GoogleMaps Salton Sea, 33.197°N, 115.8452°W, August 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16463); GoogleMaps Salton Sea, 33.1872°N, 115.8376°W, August 2001, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16464); GoogleMaps Salton Sea, 33.173°N, 115.8518°W, July 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16465); GoogleMaps Salton Sea, 33.2039°N, 115.8407°W, August 2001, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16466); GoogleMaps 3 miles down dirt road off Olgilby Road headed N road on left, 32.7965°N, 114.871°W, 9 May 2001, one ♀, M. Hedin; D. Wood, DMNS ( DMNS ZA.16467); GoogleMaps Algodones Sand Dunes Cahuilla Ranger Station Gecho Road just S of Highway 78, 32.94°N, 115.13°W, 8 October 2004, one ♀, Wendell R. Icenogle, DMNS ( DMNS ZA.17219); GoogleMaps Algodones Sand Dunes Ted Kipf Road 11/2 & S of Highway 78 ( GIAMIS), 32.76°N, 114.84°W, 61 m, 8 September 2005, one ♀, Wendell R. Icenogle, sand dunes below low Palo Verde tree limb, DMNS ( DMNS ZA.17248); GoogleMaps Algodones sand dunes Ted Kipf Road 1.5 miles S Highway 78 Chamis, 33.02°N, 115.1°W, 207 m, 9 September 2005, one ♂, Wendell R. Icenogle, DMNS ( DMNS ZA.17279); GoogleMaps Salton Sea, 33.20293°N, 115.84905°W, 98 m, August 2001, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.19092); GoogleMaps Highway 78 at junction San Felipe Creek 10.5 miles W. junction Highway 86, 33.12563°N, 116.0443°W, 195 m, 26 September 2009, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25437); GoogleMaps Highway 78 at junction San Felipe Creek, 10.5 miles W. junction Highway 86, 33.12563°N, 116.0443°W, 195 m, 17 June 2010, one ♂, Wendell R. Icenogle, Alcohol Sprayed, At Lights, DMNS ( DMNS ZA.25439); GoogleMaps Highway 78 at junction, San Felipe Creek, 10.5 miles W. junction Highway 86, 33.1256°N, 116.0443°W, 109 m, 7 June 2008, one ♂, Wendell R. Icenogle, Alcohol Sprayed, At Lights, DMNS ( DMNS ZA.25442); GoogleMaps Highway 78 at junction, San Felipe Creek, 10.5 miles W. junction Highway 86, 33.1256°N, 116.0443°W, 7 m, 1 May 2008, one ♂, Wendell R. Icenogle, Alcohol Sprayed, At Lights, DMNS ( DMNS ZA.25443); GoogleMaps Imperial Sand Dunes, 32.80883°N, 114.89218°W, 545 m, 15 May 2021, one ♂, one ♀, Paula E. Cushing; E.L. Garcia, Pitfall trap, DMNS ( DMNS ZA.42066); GoogleMaps Imperial Sand Dunes, 32.8105°N, 114.89265°W, 545 m, 15 May 2021, one ♂, one ♀, Paula E. Cushing; E.L. Garcia, DMNS ( DMNS ZA.42071); GoogleMaps San Bernardino Co.: Pisgah Crater, 34.756044°N, 116.38388°W, 392 m, 22 August 1968, one ♂, W. Savary; R.M. Haradon, CAS ( CASENT _NoNumber); GoogleMaps Pisgah Lava Flow, 34.756044°N, 116.38388°W, 472m, 1 August 1974, one ♂, B. Banta, CAS ( CASENT 9033500); GoogleMaps Pisgah Lava Flow, 34.756044°N, 116.38388°W, 472 m, 28 July 1956, one juvenile, B. Banta, CAS ( CASENT 9033508); GoogleMaps Pisgah Lava Flow, 34.756044°N, 116.38388°W, 488 m, 24 May 1960, one ♂, B. Banta, CAS ( CASENT 9033511); GoogleMaps Marine Corps Air Ground Combat Center, 34.2994°N, 116.32067°W, August 1999, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16442); GoogleMaps Marine Corps Air Ground Combat Center, 34.2998°N, 116.3003°W, July 1999, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16443); GoogleMaps Marine Corps Air Ground Combat Center, 34.3177°N, 116.26689°W, 816 m, October 1999, one ♀, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16448); GoogleMaps Marine Corps Air Ground Combat Center, 34.2834°N, 116.2998°W, 780 m, July 1999, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16449); GoogleMaps Joshua Tree National Park, 33.90925°N, 115.85617°W, May 2000, one ♀, Jack Brookhart, DMNS ( DMNS ZA.16450); GoogleMaps Marine Corps Air Ground Combat Center, 34.2826°N, 116.2414°W, August 1999, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16451); GoogleMaps Maine Corps Air Ground Combat Center, 34.3177°N, 116.26689°W, August 2000, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16452); GoogleMaps Marine Corps Air Ground Combat Center, 34.2998°N, 116.3003°W, 766 m, June 2001, one juvenile, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16453); GoogleMaps Marine Corps Air Ground Combat Center, 34.2994°N, 116.32067°W, 804 m, July 1999, one ♂, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16454); GoogleMaps Joshua Tree National Park, 33.90925°N, 115.85617°W, 539 m, May 2000, one juvenile, USGS San Diego, Pitfall Trap Array, DMNS ( DMNS ZA.16455); GoogleMaps Twentynine Palms junction Utah Trail & Amboy Road, 34.1652°N, 116.0368°W, 207 m, 2 August 2006, one ♂, Wendell R. Icenogle, Sand dunes nearby, ground below yellowish street light, DMNS ( DMNS ZA.17246); GoogleMaps 29 Palms West of Surprise Springs, 34.18°N, 116.167°W, 1–30 June 2007, three ♀, three juveniles, G. Pratt, DMNS ( DMNS ZA.22756); GoogleMaps Coachella Valley at Train Station 1/ 2 mile S Junction Inoian Cyn Drive and Highway 10, 33.897367°N, 116.54835°W, 24 May 2007, one ♂, Wendell R. Icenogle, DMNS ( DMNS ZA.24696); GoogleMaps Wonder Valley, Amboy Road, 8.5 miles E. Twentynine Palms (at Adobe Road junction), 34.1657°N, 115.9037°W, 7 m, 2 May 2007, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25444); GoogleMaps Coachella Valley, Amtrak Station, 5 miles S junction Indian Canyon Drive and Highway 10, 33.89736°N, 116.54835°W, 487 m, 7 September 2009, one ♂, Wendell R. Icenogle, DMNS ( DMNS ZA.25456); GoogleMaps Twentynine Palms, Amboy Road 1 mile E junction Adobe Road, 34.164917°N, 116.038167°W, 550 m, 19 September 2011, one ♀, one juvenile, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.28407); GoogleMaps Twentynine Palms,AmboyRoad 1mileEjunctionAdobeRoad, 34.164917°N, 116.038167°W, 550 m, 25 July 2011, one♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.28408); GoogleMaps Twentynine Palms,Amboy Road 1mile E junction Adobe Road, 34.164917°N, 116.038167°W, 550 m, 29 August 2011, one ♀, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.28409); GoogleMaps Twentynine Palms, Amboy Road 1 mile E junction Adobe Road, 34.164917°N, 116.038167°W, 550 m, 17 October 2011, one ♀, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.28410); GoogleMaps Twentynine Palms, Amboy Road 1 mile E junction Adobe Road, 34.164917°N, 116.038167°W, 550 m, 1 August 2009, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.28411); GoogleMaps Amboy Road, 8.5 miles E. of Twentynine Palms (at Adobe Road Junction), 34.1657°N, 115.903383°W, 81 m, 30 July 2009, one ♀, Wendell R. Icenogle, On pavement below lights on building, DMNS ( DMNS ZA.29497); GoogleMaps Junction Amboy Road and Utah Trail, 34.09915°N, 116.02208°W, 82 m, 21 July 2009, one ♂, Wendell R. Icenogle, DMNS ( DMNS ZA.33730); GoogleMaps Amboy Road just W junction Utah Trail, 34.16458°N, 116.0382°W, 472 m, 26 August 2017, one ♂, Wendell R. Icenogle, At lights, On sand drifts and pavement, DMNS ( DMNS ZA.42121); GoogleMaps Amboy Road just W junction Utah Trail, 34.16458°N, 116.0382°W, 472 m, 26 April 2017, one ♂, Wendell R. Icenogle, At lights, On sand drifts and pavement, DMNS ( DMNS ZA.42127); GoogleMaps Amboy Road just W junction Utah Trail, 34.16458°N, 116.0382°W, 472 m, 3 September 2018, one ♂, Wendell R. Icenogle, At lights, On sand drifts and pavement, DMNS ( DMNS ZA.42128); GoogleMaps Amboy Road, 8.5 miles E of Twentynine Palms, Wonder Valley Community Center (Blower Road), 34.16567°N, 115.9038°W, 472 m, 9 May 2007, one ♂, Wendell R. Icenogle, At lights, DMNS ( DMNS ZA.42176); GoogleMaps Amboy Road, 8.5 miles E of Twentynine Palms, Wonder Valley Community Center (Blower Road), 34.16567°N, 115.9038°W, 17 May 2007, one ♂, Wendell R. Icenogle, At lights, DMNS ( DMNS ZA.42177); GoogleMaps San Diego County: Amboy Road, 8.5 miles E of Twentynine Palms, Wonder Valley Community Center (Blower Road), 34.16567°N, 115.9038°W, 3 June 2007, one ♂, Wendell R. Icenogle, At lights, DMNS ( DMNS ZA.42178); GoogleMaps Amboy Road, 8.5 miles E of Twentynine Palms, Wonder Valley Community Center, Blower Road, 34.16567°N, 115.9038°W, 2 May 2010, one ♂, Wendell R. Icenogle, At lights, DMNS ( DMNS ZA.42179); GoogleMaps Junction of Palm Canyon Road and Borrego Valley Road, Borrego Springs, 33.255782°N, 116.374497°W, 208 m, no date, three ♂, one ♀, W. Savary; R.M. Haradon, CAS ( CASENT 9033507); GoogleMaps Ocotillo Circle, just N of junction Palm Canyon Drive, 33.25758°N, 116.385083°W, 279m, 27 August 2008, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25435); GoogleMaps Ocotillo Circle, just N of junction Palm Canyon Drive, 33.257583°N, 116.385083°W, 195 m, 16 September 2009, one ♀, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25436); GoogleMaps Ocotillo Circle, just N junction Palm Canyon Drive, 33.257583°N, 116.385083°W, 7 m, 19 August 2010, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25440); GoogleMaps Highway 78, Ocotillo Wells Ranger Station (State Vehicular Recreation Area), 33.155°N, 116.168°W, 195 m, 12 September 2008, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25441); GoogleMaps Ocotillo Circle, just N junction Palm Canyon Drive, 33.25758°N, 116.385083°W, 7 m, 12 June 2008, one ♂, Wendell R. Icenogle, Alcohol Sprayed, DMNS ( DMNS ZA.25438); GoogleMaps Riverside County: 8 miles NW Palm Springs, 33.912332°N, 116.644096°W, 472 m, 1 May 1959, one ♂, M. Wasbauer, CAS ( CASENT 9033506); GoogleMaps Dos Palmas Reserve (San Andres Palm Oasis) 5 miles E Salton Sea State Rec Area headquarters Highway 111, 33.51°N, 115.89°W, 3 April 2004, one ♂, Wendell R. Icenogle, path to Palm Oasis, DMNS ( DMNS ZA.17210); GoogleMaps Coachella Valley, Palm Springs Amtrak Station 1/ 2 miles S junction Indian Canyon Drive Highway I-10, 33.8974°N, 116.5483°W, 21 May 2006, one ♀, Wendell R. Icenogle, Sand dunes, DMNS ( DMNS ZA.17213); GoogleMaps Coachella Valley Palm Springs Amtrak Station 1/ 2 mile S junction Indian Canyon Drive and Highway I-10, 33.8974°N, 116.5484°W, 549 m, 21 September 2006, one ♀, Wendell R. Icenogle, Netted, Sand dunes nearby, on concrete walkway below yellowish lights, DMNS ( DMNS ZA.17284); GoogleMaps Coachella Valley Palm Springs Amtrak Station 1/ 2 mile S junction Indian Canyon Drive and Highway I-10, 33.8974°N, 116.5484°W, 107 m, 24 May 2006, one ♂, Wendell R. Icenogle, Sand dunes nearby, pavement below yellowish lights, DMNS ( DMNS ZA.17285); GoogleMaps Cottonwood Road, 1/ 10 mile S Junction Snow Creek Road, 33.8897725°N, 116.6841503°W, 545 m, 1 May 2011, one ♂, Wendell R. Icenogle, DMNS ( DMNS ZA.42018); GoogleMaps Coachella Valley Palm Springs, Amtrak Station 1/ 2 mile S junction Indian Canyon Drive and Highway I-10, 33.8974°N, 116.54584°W, 71 m, 24 May 2006, one ♀, Wendell R. Icenogle, DMNS ( DMNS ZA.17235); GoogleMaps Coachella Valley Palm Springs Nature Station 1/ 2 mile S junction Indian Canyon Drive and Highway I-10, 33.8974°N, 116.5484°W, 3 m, 4 September 2006, one ♀, Wendell R. Icenogle, Sand dunes nearby, on ground beside concrete walkway under yellowish lights, DMNS ( DMNS ZA.17244); GoogleMaps Utah: Washington Co.: West of Gunlock Road, ~ 160 feet, ~ 1.8 miles south of Gunlock State Park, 37.2297°N, 113.780503°W, 1056 m, 19 July 2020, one ♂, Zach J. Valois, At lights, DMNS ( DMNS ZA.42397). GoogleMaps

Diagnosis

Chanbria regalis can be distinguished from C. serpentinus by the presence of fixed finger dentition on the male chelicerae and by a more robust base of the fixed finger. This species can be distinguished from all other Chanbria by a tapering sigmoidal male FF. Individuals are generally absent of dark pigmentation.

Measurements

All measurements are reported as averages, and ranges are in parentheses.

Males (n = 17): CL: 6.096 (3.154 –7.829); CH: 2.060 (1.189 – 2.589); FFH: 0.587 (0.356 –0.709); tip of MF to MM: 1.726 (1.078 –2.407); tip of MF to MP: 2.041 (1.309 –2.994); PL: 24.629 (20.880 –29.289); LI: 12.506 (10.063 –15.665); LIV: 21.618 (16.587 –27.282); PPW: 4.079 (3.126 –5.319); PPL: 3.014 (2.261 –3.793); TL: 22.289 (17.467 –27.841).

Females (n = 9): CL: 6.06 (3.367 –7.354); CH: 2.154 (1.1555 – 2.612); FFH: 0.682 (0.333 –0.939); tip of MF to MD: 1.644 (0.733 –2.124); tip of MF to MP: 1.830 (1.384 –2.596); tip of FF to FD: 0.905 (0.759 –1.020); PL: 20.403 (17.190 –23.738); LI: 11.633 (10.335 –13.182); LIV: 21.268 (18.046 –23.454); PPW: 4.385 (3.832 –5.200); PPL: 2.977 (2.219–4); TL: 23.467 (19.818 –26.549); GOL: 1.401 (1.244 –1.557); GOW: 0.619 (0.492 –0.746); GOD: 1.930 (1.7425 –2.117).

Redescription: males

Coloration: Overall coloration light tan. Legs infuscate distally near ends of tibiae, femurs, and tarsi. Pedipalps darken near end of the tibiae. Palpal tibia, metatarsi, and tarsi darker reddish orange. Propeltidium darkens slightly along margins. FF and MF of the chelicerae darken distally.

Chelicera: FF sigmoidal, with dentition present ventrally. In some populations, dentition is reduced. Between three and four teeth present on MF. MP tooth largest, prominent, and recurved. When present, MSD tooth is smallest. Fondal notch absent. Fondal teeth vary in length.

Redescription: females

Coloration: Coloration as in males.

Chelicera: FF with seven to nine teeth. The following FF states were recorded among C. regalis females: seven teeth with FF formula FD- 2FSD-FM-2FSM-FD, eight teeth with FD- 2FSD-FM-3FSM-FP, or nine teeth with FD- 3FSD-FM-3FSM-FP. The last two states are the most common. Moveable finger with four teeth. MP tooth largest, followed by MM tooth, with two smaller MSM teeth between them. Many of the chelicerae examined have FST and MST.

Operculum: Opercular morphology is highly variable between individual females. AMNH allotype with rounded opercular plates resembling isosceles triangles. Other morphologies present include elongate tapered lobes in specimen DMNS ZA.16442, broad anterior pillars with laterally curving lobes resembling an L-shape in specimen DMNS ZA.17213, or elongate, ovoid lobes as in specimen DMNS ZA.44238 ( Fig. 7 View Figure 7 ).

Distribution

Sonoran Desert. This species is wide ranging, occurring from the southwestern corner of Utah to the Sonoran Desert/Peninsular Desert in Baja California. It is restricted primarily to the eastern side of the Colorado River. One record is from the western side on the southern end of the distribution in Pima County, Arizona, suggesting that they might occur on both sides of the southern end of the river.

Discussion

Individuals of this widespread species are notable for a high level of intraspecific morphological variation in both the male chelicerae and the female genital operculum ( Fig. 7A–D View Figure 7 ), and these structures have been used historically for species delimitation in eremobatids ( Muma 1951, 1962). Such variability, especially in the relative lengths of the fondal teeth and general shape of the FF of the male chelicerae, challenges previous taxonomic assumptions about the usefulness of these ‘sexually selected’ structures for delimiting species within the genus. Chanbria regalis and C. rectus were differentiated by Muma (1962) based on the lack of curvature of the dorsal profile of the male FF (Supporting Information, Fig. S5 View Figure 5 ) and the presence or absence of palpal scopula (papillae). However, the results of the PCAs from the SNP and mitochondrial dataset, the small K80 genetic distance, the relatively recent divergence time, and the lack of a distinct geographical barrier support the synonymization of these two species. More sampling from populations across the C. regalis range is necessary to determine whether the variable morphological traits we observed are stable across the geographical range or are aberrant traits. Given the little divergence in genetic data and inconsistent morphological traits, we are therefore in favour of a single-species hypothesis that maintains subtle variation of traits across populations.

Owing to this, our genetic results, and the level of intraspecific variation that we observe within this clade, in addition to our observation of the type material, we suggest the synonymization of Chanbria tehachapianus with C. regalis . This decision is motivated by the nearly identical morphology that C. tehachapianus shares with individuals of C. regalis , and the diagnostics used to erect the species [i.e. constricted base at the FF and lack of scopula (also known as papillae; Muma 1962)] are insufficient to maintain the species status confidently. Additionally, a lack of known specimens other than the holotype identified as C. tehachapianus and the lack of a distinct geographical barrier between its collection locality and the known range of C. regalis are evidence in favour of synonymizing these two species.

The high degree of variable morphology in the opercula of female C. regalis suggests that mating complementarity in C. regalis is not dependent on the shape of the genital opercular plate, and instead internal structures might be more important for facilitating mating complementarity than external structures, as noted in other studies ( Garcia et al. 2024). Alternatively, this variation might simply be explained by the recent divergence and is an example of characters that have yet to reach fixation.