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The Critically Endangered Chapman's pygmy chameleon Rhampholeon chapmanorum is endemic to the low elevation rainforest of the Malawi Hills in southern Malawi. Much of this forest has been converted to agriculture and it was uncertain whether chameleon populations have persisted. We used current and historical satellite imagery to identify remaining forest patches and assess deforestation. We then surveyed forest patches for the presence of this chameleon, and assessed its genetic diversity and structure. We estimated that 80% of the forest has been destroyed since 1984, although we found extant populations of the chameleon in each of the patches surveyed. Differentiation of genetic structure was strong between populations, suggesting that gene flow has been impaired. Genetic diversity was not low, but this could be the result of a temporal lag as well as lack of sensitivity in the mitochondrial marker used. Overall, the impact of forest loss is assumed to have led to a large demographic decline, with forest fragmentation preventing gene flow. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted on the sympatry of Trioceros species of chameleons, including T. montium, T. pfefferi and T. q. quadricornis, in a tropical forest in Cameroon from February 15, 2011 to March 3, 2011. Topics discussed include recording of the position of specimens from different locations through global positioning system (GPS), smaller dietary niche segregation of T. pfefferi compared to T. montium and T. q. quadricornis and the observations of their syntopic occurrence.

Temperature strongly affects whole-organism performance through its effect on muscle contractile rate properties, but movements powered by elastic recoil are liberated from much of the performance decline experienced by muscle-powered movements at low temperature. We examined the motor control and muscle contractile physiology underlying an elastically powered movement - tongue projection in chameleons - and the associated muscle powered retraction to test the premise that the thermal dependence of muscle contractile dynamics is conserved. We further tested the associated hypothesis that motor control patterns and muscle contractile dynamics must change as body temperature varies, despite the thermal robustness of tongue-projection performance. We found that, over 14-26°C, the latency between the onset of the tongue projector muscle activity and tongue projection was significantly affected by temperature (Q10 of 2.56), as were dynamic contractile properties of the tongue projector and retractor muscles (Q10 of 1.48-5.72), supporting our hypothesis that contractile rates slow with decreasing temperature and, as a result, activity durations of the projector muscle increase at low temperatures. Over 24-36°C, thermal effects on motor control and muscle contractile properties declined, indicating that temperature effects are more extreme across lower temperature ranges. Over the entire 14-36°C range, intensity of muscle activity for the tongue muscles was not affected by temperature, indicating that recruitment of motor units in neither muscle increases with decreasing temperature to compensate for declining contractile rates. These results reveal that specializations in morphology and motor control, not muscle contractile physiology, are responsible for the thermal robustness of tongue projection in chameleons. [ABSTRACT FROM AUTHOR]

Information on micrurus alleni from Florida including informations related to topics like its diet, the habitat in which it is found, and its physical traits is presented.

An abstract of the article "Anolis Roquet (Martinique' Anole) by Christopher V. Anderson and colleagues is presented.

We studied an established population of Furcifer oustaleti (Oustalet's Chameleon) in southeastern Florida to understand aspects of reproductive biology in this nonnative species. Reproduction of Oustalet's Chameleon had not been documented in the field in Florida, and limited information is available about its reproduction in its native range. We conducted surveys from July 2011 to October 2012 in the Persea americana (Avocado) grove where this species was introduced in Miami-Dade County, FL. During these surveys, we removed more than 430 chameleons. We encountered 23 gravid females from June to October. Mean clutch size was 42.3 eggs, and we recorded a new maximum clutch size of 72 eggs. Utilizing radio-telemetry, we were able to track a gravid female to a nest cavity, and herein describe the first Oustalet's Chameleon nest in Florida. Our findings suggest that management for eradication of the species should include ongoing surveys, with removal efforts intensified from June to October, when females are known to be gravid. [ABSTRACT FROM AUTHOR]

Numerous chameleon species possess an out-pocketing of the trachea known as the gular pouch. After surveying more than 250 specimens, representing nine genera and 44 species, we describe two different morphs of the gular pouch. Species of the genera Bradypodion and Chamaeleo, as well as Trioceros goetzei, all possess a single gular pouch (morph one) formed from ventral expansion of soft tissue where the larynx and trachea meet. Furcifer oustaleti and Furcifer verrucosus possess from one to four gular pouches (morph two) formed by the expansion of soft tissue between sequential hyaline cartilage rings of the trachea. In Trioceros melleri, examples of both morphs of the gular pouch were observed. Morphometric data are presented for 100 animals representing eight species previously known to possess a gular pouch and two additional species, Bradypodion thamnobates and Bradypodion transvaalense. In the species with the absolutely and relatively largest gular pouch, Chamaeleo calyptratus, a significant difference was found between sexes in its width and volume, but not its length. In C. calyptratus, we show that an inflated gular pouch is in contact with numerous hyoid muscles and the tongue. Coupled with the knowledge that C. calyptratus generates vibrations from the throat region, we posit that the tongue (M. accelerator linguae and M. hyoglossus) and supporting hyoid muscles (i.e., Mm. sternohyoideus profundus et superficialis and Mm. mandibulohyoideus) are involved in the production of vibrations to produce biotremors that are amplified by the inflated gular pouch and used in substrate-borne communication., (© 2019 American Association for Anatomy.)