Bioacoustics of Neduba radocantans

Etymology. l. rado “scrape” + cantans “singing”. Refers to the rasping, abrasive sound quality of the numerous minor PT in the male song. Notes. Distributed at the northern limit of the Sierranus Group, N. radocantans is sympatric with N. radicata , the species with the most southerly distribution in the Carinata Group where their elevational distributions overlap. Selection for mate recognition at a contact zone could have driven the evolution of the distinctive, elaborate song with numerous OPT in this species. The population near Kyburz, California was located with a bat detector while night driving. Males were common but no females could be found, even after trampling vegetation. N. radicata songs were heard in trees at this locality. The type locality of Finnon Lake is private property that is owned and managed by the Mosquito Volunteer Fire Association (www.gomvfa.org). The conservation prospectus of this area is unknown.

Distribution. West slope of the Sierra Nevada in the vicinity of the American River watershed. Stridulatory file. (n = 5) length 3.2–3.4 mm , 200–250 teeth, tooth density 70.6 ± 5.5 (62.5–76.9) teeth/mm. Song. (n = 19) Unique in the high PTN of 19.9 ± 3.9 (two-way ANOVA, P = 1.93×10 -15 ). The greater portion of airtime spent producing OPT makes the PTR slower (0.8 ± 0.3 s- 1, ANCOVA, P = 3.96×10 -9 ) than that of other Sierranus Group species. PTF is 16.2 ± 1.2 kHz. Karyotype. (n = 6) Unique. 2n♁ = 22 ( 2m + 18t + XmYt), T95-20, S95-62, paratopotype. Recognition. Males have both a high stridulatory file tooth density (68–73 teeth/mm) and a strongly constricted pronotum. Male N. sierranus have a similar high tooth density but the pronotum constriction is weak. N. inversa is difficult to separate but tends to have a lower stridulatory file tooth density. Female hind femora are shorter than other Sierranus and Sequoia group species. The song has the slowest PTR and highest PTN of the Sierranus Group. The latter song feature is temperature-invariate and distinct to a human listener, and thus may be used to identify this species in song surveys that lack temperature correction. Inhabiting the vicinity of the American River drainage, this species ranges the farthest north of any in the Sierranus Group ( Fig. 19 ).