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Length measurement axes in sample photographs of the studied Owens tui chub Siphateles bicolor snyderi scales and bones. Samples were obtained from 211 individuals from 16 localities from the Owens River and neighboring basins along the border between California and Nevada during summers of 2001 and 2002.
Source publication
Regression parameters for the length of several bony structures against fish body length, and for body length against body weight, were determined for Owens tui chub Siphateles bicolor snyderi, Lahontan tui chub Siphateles bicolor obesa, and hybrid swarm deriving from the two species. Two-hundred eleven individuals from 16 localities from the Owens...
Context in source publication
Context 1
... and bone lengths were measured from the focus to the posterior margin in scales; from the dorsal tip to the ventral tip in the pharyngeal arches; from the mandibular symphysis to the posterior ventral tip in dentaries; from the dorsal tip to the anterior tip in the cleithra; and from the articular process to the inferior angle in the opercula (Figure 2). Bone lengths were measured from both left and right bones (as per Hansel et al. 1988;Prenda and Granado-Lorencio 1992) and measurements were averaged; only one measurement was used when a single bone was available. ...
Citations
... Based on archaeological data, Talcott (2019) argued that thicktail chub, along with other endemic Delta fish species, were harvested when flood waters receded in the summer, leaving spawning fish stranded in residual pools where they could be caught easily by hand, net, or basket. Despite its popularity in midden deposits, Yokuts thought that these fish were not very palatable (Latta 1949;Wallace 1978). ...
... Robust hybrid populations now occupy lakes and streams throughout the Owens River basin (Chen et al., 2007). The phenotypic consequences of this rapid introgression and its effects on population fitness are largely unknown (but see Galicia et al., 2015;Leunda et al., 2013). ...
Introgressive hybridization may erode phenotypic divergence along environmental gradients, collapsing locally adapted populations into a hybrid swarm. Alternatively, introgression may promote phenotypic divergence by providing variation on which natural selection can act. In freshwater fishes, water flow often selects for divergent morphological traits in lake versus stream habitats. We tested the effects of introgression on lake–stream morphological divergence in the minnow Owens Tui Chub (Siphateles bicolor snyderi), which has been rendered endangered by introgession from the introduced Lahontan Tui Chub (Siphateles bicolor obesa). Using geometric morphometric analysis of 457 individual Tui Chub from thirteen populations, we found that both native and introgressing parent taxa exhibited divergent body and caudal fin shapes in lake versus stream habitats, but their trajectories of divergence were distinct. In contrast, introgressed populations exhibited intermediate body and caudal fin shapes that were not differentiated by habitat type, indicating that introgression has eroded phenotypic divergence along the lentic–lotic gradient throughout the historic range of the Owens Tui Chub. Individuals within hybrid populations were less morphologically variable than those within parent populations, suggesting hybrid adaptation to selective agents other than water flow or loss of variance by drift. Introgressive hybridization can either erode or promote adaptive phenotypic divergence along environmental gradients. We tested the effects of widespread introgressive hybridization on morphological divergence between lake and stream habitats in the minnow Tui Chub. We found that hybridization has eroded morphological divergence, but comparisons of morphological variance between parent and hybrid populations suggest this outcome may not be maladaptive.
... Live length of BL Cypriniformes fishes was estimated using regression models provided by Leunda et al. (2013) for tui chub pharyngeal, cleithrum, and opercle, and the regressions provided by Rood et al. (1995) for minnow/sucker vertebrae (Table 6). These provided size estimates from 12 to 21 cm (fork length) and 12-40 cm (standard length). ...
... Orthoptera consumption in the Great Basin and nearby regions is reflected in the archaeological record primarily by the remains of grasshoppers (Drover, 1979;Hubbell, 1942;Jones, 1948;Madsen and Kirkman, 1988;Madsen and Schmitt, 1998;Orr, 1952;Stiger, 1977) and Mormon crickets (Frison and Huseas, 1968;Frison, 1971), though other Orthoptera remains have also been recovered (Hockett, 2015). The ethnographic record is even more plentiful (Bancroft, 1889;Clark, 1904;Coville, 1897;Douglas, 1959;Egan, 1917;Essig, 1934;Fowler and Fowler, 1971;Holt, 1946;Leechman, 1944;Mooney, 1890;Parkman, 1872;Riddell, 1978;Sapir, 1907Sapir, , 1909Skinner, 1910;Wakeland, 1959). Yet the majority of Orthoptera remains in the BL units at Paisley Caves are the remains of the Jerusalem cricket, Stenopelmatus sp. ...
... Extracted bones were left to air-dry at room temperature and were photographed with a digital single-lens reflex camera (Nikon D100; 6 megapixel) with a macro lens. Further details on sample preparation for biometry along with results of bone-to-body relationships can be found elsewhere (Leunda et al. 2013). Morphometric and statistical analyses.-The ...
The Owens Tui Chub Siphateles bicolor snyderi has become endangered by introgressive hybridization with the Lahontan Tui Chub S. bicolor obesa since the 1960s. Adequate conservation strategies require prior identification of pure populations, which is usually difficult because the diagnostic features presented in the formal subspecies description do not always allow unequivocal determination of populations. In the present study, the shape and some meristic features of the scales, along with the shape of other bones with taxonomic value, were analyzed to distinguish both parental subspecies and their hybrids in samples diagnosed in a previous work using microsatellite DNA. Scales, pharyngeal arches, dentaries, cleithra, and opercula of 211 individuals from 16 localities across the Owens River and neighbouring basins in California and Nevada were compared. The results show that the meristic parameters of the scales were in agreement with values provided by Miller (1973)13.
Miller, R. R. 1973. Two new fishes, Gila bicolor snyderi and Catostomus fumeiventris, from the Owens River basin, California. Occasional Papers of the Museum of Zoology University of Michigan 667. View all references for the parental subspecies. Shape analyses were based on landmark or Fourier methods, depending on the shape characteristic of each structure. Geometric morphometric analyses provided variable discriminatory power between subspecies depending on the studied bone. In scales, pharyngeal arches, and dentaries, the derived morphological patterns matched the shape descriptions set forth by Miller (1973)13.
Miller, R. R. 1973. Two new fishes, Gila bicolor snyderi and Catostomus fumeiventris, from the Owens River basin, California. Occasional Papers of the Museum of Zoology University of Michigan 667. View all references for both parental subspecies. In all cases, the observed morphometric variability of hybrids was too high to separate them from parental subspecies. However, joint analysis of the five structures produced groupings that were concordant with the genetic analyses: localities of parental subspecies in separate groups and an intermediate group with the hybrid swarm localities that was morphologically closer to Lahontan. Finally, a new derived parameter (the ratio between scale lengths from the anterior and posterior body) is suggested as a promising tool for rapid discrimination of Owens Tui Chub from Lahontan Tui Chub and their hybrid populations.Received August 5, 2014; accepted December 4, 2014
