Polly K. Phillips

Thermal responses in some Eastern Cape African Cicadas (Hemiptera: Cicadidae)

Abstract 1. Thermal responses were measured in cicadas collected in the Eastern Cape Province of South Africa. 2. The thermal responses of 22 species from 5 biomes were determined. 3. Shade-seeking temperature was the most variable and related to the various biomes. 4. Mean shade-seeking temperature was greatest for species inhabiting the thicket biome and lowest for species inhabiting the forest biome. 5. The animals that live in the thicket biome may adapt to the greater thermal stress to take advantage of a habitat that permits lower predation pressure. 6. There is a correlation between body size and shade-seeking temperatures with smaller species exhibiting lower thermal responses within a particular habitat. This may be related to the greater heat exchange in smaller species. 7. Heat torpor temperatures did not differ between the various biomes.

Reevaluation of the Diceroprocta texana Species Complex (Hemiptera: Cicadoidea: Cicadidae)

ABSTRACT The Diceroprocta texana species complex is currently composed of Diceroprocta texana texana (Davis, 1916) and Diceroprocta texana lata Davis, 1941. We analyzed physiological, morphological, and biogeography to determine whether these taxa in fact represent two distinct species rather than subspecies. There are statistically significant differences in morphological, acoustic, and thermal parameters as well as the biogeographic patterns of the two taxa. From these data, we suggest that the two taxa actually represent two species and that D. texana lata be elevated to species full species rank with the name Diceroprocta lata Davis, 1941 n. stat. We provide the first records of D. lata collected in the United States.

Hot-blooded singers: endothermy facilitates crepuscular signaling in African platypleurine cicadas (Hemiptera: Cicadidae: Platypleura spp.)

The cicada genus Platypleura has a wide distribution across Africa and southern Asia. We describe endothermic thermoregulation in four South African species that show crepuscular signaling behavior. This is the first evidence of thermoregulation in platypleurine cicadas. Field measurements of body temperature (Tb) show that these animals regulate Tb through endogenous heat production. Maximum Tb measured was 22.1°C above ambient temperature during calling activity at dusk. The mean Tb during dusk activity did not differ from the mean Tb during diurnal activity. A unique behavior for cicadas, a temperature-dependent telescoping pulsation of the abdomen, was observed in the laboratory during endogenous warm-up. This behavior is part of a unique method of heat generation in endothermic cicadas. Males generally call from trunks and branches within the canopy and appear to use endothermy even when the sun is available to elevate Tb. Endothermy may provide the cicadas with the advantage of decreasing predation and acoustic competition by permitting calling from perches that most complement their cryptic coloration patterns and that ectotherms cannot use due to thermal constraints. In addition, endothermy may permit calling activity during crepuscular hours when atmospheric conditions are optimal for acoustic communication and predation risks are minimal.

Thermal adaptation and diversity in tropical ecosystems: evidence from cicadas (Hemiptera, Cicadidae).

The latitudinal gradient in species diversity is a central problem in ecology. Expeditions covering approximately 16°54′ of longitude and 21°4′ of latitude and eight Argentine phytogeographic regions provided thermal adaptation data for 64 species of cicadas. We test whether species diversity relates to the diversity of thermal environments within a habitat. There are general patterns of the thermal response values decreasing in cooler floristic provinces and decreasing maximum potential temperature within a habitat except in tropical forest ecosystems. Vertical stratification of the plant communities leads to stratification in species using specific layers of the habitat. There is a decrease in thermal tolerances in species from the understory communities in comparison to middle level or canopy fauna. The understory Herrera umbraphila Sanborn & Heath is the first diurnally active cicada identified as a thermoconforming species. The body temperature for activity in H. umbraphila is less than and significantly different from active body temperatures of all other studied species regardless of habitat affiliation. These data suggest that variability in thermal niches within the heterogeneous plant community of the tropical forest environments permits species diversification as species adapt their physiology to function more efficiently at temperatures different from their potential competitors.

A new species of the genus Beameria (Hemiptera: Cicadidae) from North America

Cicadas of the genus Beameria Davis are small, grass dwelling species found across much of western North America. We provide the first detailed description of the genus and describe the new species Beameria ansercollis sp. nov. Sanborn and M. Heath with this work. The morphology, biogeography, song parameters and thermal tolerances of the new and known species of Beameria are described and comparisons between the species are made. There are significant statistical differences in morphology, song parameters and thermal tolerances between the species of the genus. The biogeography of all species is illustrated. A key to the species of Beameria is provided.

Temperature responses and habitat selection by mangrove cicadas in Florida and Queensland (Hemiptera Cicadoidea)

The thermal responses of cicadas inhabiting mangrove swamps in Queensland, Australia and in Florida, USA show a remarkable convergence in selected temperature and thermal tolerance. Cicadas inhabiting the foreshore, Arunta perulata (Guérin-Méneville 1831) in Queensland, and Diceroprocta biconica (Walker 1850) in Florida, use similar habitats and the same activity period. Arunta perulata and Diceroprocta biconica show nearly identical temperature selection (32.8 ± 2.57 °C [n = 10] and 33.2 ± 2.86 °C [n = 26] respectively) and temperature tolerance (45.7 ± 1.53 °C [n = 8] and 45.3 ± 1. 59 °C [n = 27] respectively). Arunta interclusa (Walker 1858), which lives in the intertidal region, has lower temperature selection (29.4 ± 1.11 °C [n = 7]), sings earlier in the day and has higher temperature tolerance (47.8 ± 0.78 °C [n = 8]) than the other species. These observations suggest that adaptation to habitat rather than phylogenetic origin controls thermal responses in cicadas.

Elevation of a Subspecies of tibicen (Hemiptera: Cicadoidea: Cicadidae) to a Full Species

Abstract The Tibicen bifidus species complex is composed of T. b. bifidus (Davis, 1916) and T. b. simplex Davis, 1941. We analyzed biogeographical, morphological, and physiological parameters to determine if these taxa represent two species. There are significant differences in biogeography, as well as selection of host-plant and several morphological characteristics. Comparisons of their calling songs approach statistical significance. Sound-pressure level of alarm calls and thermal responses of the two taxa do not differ significantly. Our data suggest that the two taxa represent distinct species.

Endothermy in African Platypleurine Cicadas: The Influence of Body Size and Habitat (Hemiptera: Cicadidae)

The platypleurine cicadas have a wide distribution across Africa and southern Asia. We investigate endothermy as a thermoregulatory strategy in 11 South African species from five genera, with comparisons to the lone ectothermic platypleurine we found, in an attempt to ascertain any influence that habitat and/or body size have on the expression of endothermy in the platypleurine cicadas. Field measurements of body temperature (Tb) show that these animals regulate Tb through endogenous heat production. Heat production in the laboratory elevated Tb to the same range as in animals active in the field. Maximum Tb measured during calling activity when there was no access to solar radiation ranged from 13.2° to 22.3°C above ambient temperature in the five species measured. The mean Tb during activity without access to solar radiation did not differ from the mean Tb during diurnal activity. All platypleurines exhibit a unique behavior for cicadas while warming endogenously, a temperature‐dependent telescoping pulsation of the abdomen that probably functions in ventilation. Platypleurines generally call from trunks and branches within the canopy and appear to rely on endothermy even when the sun is available to elevate Tb, in contrast to the facultative endothermy exhibited by New World endothermic species. The two exceptions to this generalization we found within the platypleurines are Platypleura wahlbergi and Albanycada albigera, which were the smallest species studied. The small size of P. wahlbergi appears to have altered their thermoregulatory strategy to one of facultative endothermy, whereby they use the sun when it is available to facilitate increases in Tb. Albanycada albigera is the only ectothermic platypleurine we found. The habitat and host plant association of A. albigera appear to have influenced the choice of ectothermy as a thermoregulatory strategy, as the species possesses the metabolic machinery to elevate to the Tb range observed in the endothermic species. Therefore, size and habitat appear to influence the expression of thermoregulatory strategies in African platypleurine cicadas.

The genus Neocicada Kato, 1932 (Hemiptera: Cicadomorpha: Cicadidae), with descriptions of three new species

Abstract.  A revision of the genus Neocicada Kato, 1932 previously known only by two species and a subspecies (N. hieroglyphica (Say), N. hieroglyphica var. johannis (Walker), N. chisos (Davis)), is expanded to include three additional species described here: N. australamexicana, sp.n., N. centramericana, sp.n., and N. mediamexicana, sp.n. To facilitate comparison of the species and for consistency and completeness in descriptions, the original genus and species descriptions have been expanded and keys to the genus have been included. The biogeography and eco‐ethology of the genus are discussed, including habitat preference and song production activity. This genus appears unrelated to any other in North America, its closest relative being the genus Cicada L., 1758, from which it is separated geographically.

Neotype and Allotype Description of Tibicen superbus (Hemiptera: Cicadomorpha: Cicadidae) with Description of Its Biogeography and Calling Song

Abstract We redescribe the cicada Tibicen superbus (Fitch, 1855) and designate a neotype and an allotype for the species. The biogeography of the species is provided, including the first records from Mexico. The calling song for the species also is described.