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The only known population of Conolophus marthae (Reptilia, Iguanidae) and a population of C. subcristatus are syntopic on Wolf Volcano (Isabela Island, Galápagos). No gene flow occurs suggesting that effective reproductive isolating mechanisms exist between these two species. Chemical signature of femoral pore secretions is important for intra- and inter-specific chemical communication in squamates. As a first step towards testing the hypothesis that chemical signals could mediate reproductive isolation between C. marthae and C. subcristatus, we compared the chemical profiles of femoral gland exudate from adults caught on Wolf Volcano. We compared data from three different years and focused on two years in particular when femoral gland exudate was collected from adults during the reproductive season. Samples were processed using Gas Chromatography coupled with Mass Spectrometry (GC–MS). We identified over 100 different chemical compounds. Non-Metric Multidimensional Scaling (nMDS) was used to graphically represent the similarity among individuals based on their chemical profiles. Results from non-parametric statistical tests indicate that the separation between the two species is significant, suggesting that the chemical profile signatures of the two species may help prevent hybridization between C. marthae and C. subcristatus. Further investigation is needed to better resolve environmental influence and temporal reproductive patterns in determining the variation of biochemical profiles in both species.

The extensive use of pesticides in agricultural environments produces drastic effects on wildlife, hence the need for less invasive indicators of environmental stress to monitoring the impact of agriculture treatments on biological systems. Fluctuating asymmetry (FA), as measure of developmental instability, has recently been proposed as reliable biomarker of populations stress due to environmental disturbance. We investigate femoral pores (FP) and dorsal head shape (HS) traits in populations of the Italian wall lizard inhabiting agricultural environments to examine whether different pesticide exposures (conventional, organic and control) can cause distinctive degree of FA. High-resolution photographs of FP and HS were taken in the field with a digital camera. The number of FP were counted twice on both sides and HS was analysed using geometric morphometrics with 25 landmarks and 12 semilandmarks. Individuals under conventional management showed higher levels of FA compared to control ones, and females exhibited higher FA levels than males for the FP. However, no significant difference was found for the HS trait. Our study provided evidence that FA may have a real potential as biomarker of population stress in wall lizards, highlighting the importance in the choice of the experimental design and the traits adopted for estimating DI.

Identifying the processes that lead to the evolution and maintenance of links between colour morphs and behavioural strategies has implications for the evolution of reproductive isolation and sympatric speciation. Sexual selection may play a significant role in the evolution of colour pattern complexity in reptiles, particularly when there are fitness consequences associated with mating with males of different colour morphs. In this article, we explored if common wall lizard females (Podarcis muralis) actively select males according to their morph in a colour-assortative pattern using a multiple-choice experiment with both visual and chemical cues. We failed to identify female active mate choice, as females did not choose males based on male colouration or femoral pore secretions. Indeed, females equally entered the three preference compartments and spent nearly the same amount of time within them, irrespective of both colour and odour of males. Consequently, our results do not support the hypothesis that colour polymorphism in this species may be driven by colour-assortative mating promoted by females. However, we cannot exclude the possibility that females may choose males according to their colour following a flexible choice strategy, nor the possibility that females actively discriminate among males according to qualities that are not directly related to morph-specific strategies.

Animals communicate via a variety of sensory channels and signals. Studies on acoustic and visual communication systems suggest that differences in the physical environment contribute to the variety of signalling behaviour, with species investing in those signals that are transmitted best under the local conditions. Whether or not environmental tuning also occurs in chemical communication systems has received much less attention. In the present study, we examined the effect of several aspects of the physical environment on the chemical communication system of lacertid lizards (family Lacertidae). The numbers of femoral pores are used as a proxy reflecting how much a particular species invests in and relies upon chemical signalling. Femoral pores are specialized epidermal structures that function as a secretion channel for the waxy substance produced by glands. In some lacertid species, the secretion carries infochemicals that play an important role in social communication. The number of femoral pores varies considerably among species. We have compiled data on femoral pore numbers for 162 species and tested for the effects of climate and substrate use. After correcting for body size and taking the phylogenetic relationships among the species into account, we found no effect of climate conditions or latitude on species pore numbers. Substrate use did affect pore numbers: shrub-climbing species tended to have fewer femoral pores than species inhabiting other substrates. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114, 44–57.

Exposure to aggressive or courtship displays of conspecifics has been shown to alter the physiology and behaviour of observers. However, these effects are dependent on the information content of signals. Separate courtship signals that convey redundant information may be expected to have similar effects on female reproductive physiology or behaviour, while those that contain nonredundant information are expected to have differing effects. Using a mechanized model lizard painted to resemble a male sagebrush lizard, Sceloporus graciosus, we presented female sagebrush lizards with either a stationary model or one of two male display types: push-ups, a signal used in both aggressive and courtship displays, and shudders, a display used exclusively during courtship. Females exposed to push-ups showed more rejection behaviour when later paired with a live male lizard and produced less femoral pore secretions on the first day of stimulus presentation than females exposed to shudders. However, females exposed to either display were found in closer proximity to the live male than females exposed to the stationary model. These results suggest that both components of the courtship display (push-ups and shudders) cause lasting but distinctive changes in female behaviour, supporting a ‘multiple messages’ scenario for the evolution of the two signals.

Although many animals deposit scent marks, previous studies have focused almost entirely on rodents or on the chemical structure of the signal. Here, we study the quantity and temporal pattern of chemical deposition by the territorial sagebrush lizard Sceloporus graciosus, measuring both femoral pore and fecal deposits. Specifically, we tested whether variation in deposition is a good cue of individual and sexual identity and/or whether it is more closely associated with body size and reproductive state, indicators of physiological condition. The results support the latter hypothesis. We found that although the amount of fluid deposited on a single perch (rarely quantified in mammals) carries little information on individual or sexual identity, it reflects the physiological condition and reproductive state of individual lizards and is replenished on a roughly weekly cycle, potentially providing additional information on the producer's activity level. The amount of deposition may thus provide important information to chemical receivers making mate choice and territorial defense decisions. The results further suggest that seasonal increases in gland production allow lizards to mark more sites rather than to influence the quality of the signal on a single perch.

We provide an integrative analysis of the diversity of the E. multiocellata—E. przewalskii species complex in Central and Middle Asia using morphological and molecular (COI DNA-barcoding) data. We report preliminary data on mtDNA variation within this group and clarify the taxonomic status and distribution of the members of the species complex. We also provide a description of a new Eremias species from Eastern Kazakhstan and western Mongolia, where it occurs in sympatry with E. multiocellata sensu stricto, from which it can be clearly differentiated using both morphological and molecular characters. The new species, described as Eremias dzungarica sp. nov., is assigned to the subgenus Pareremias on the basis of the following features: subocular not reaching mouth edge; one frontonasal; two supraoculars; the row of small granular scales between supraoculars and frontal with frontoparietals absent; distance between the femoral pore rows being wide; femoral pore rows not reaching knee-joint; coloration pattern with light colored ocelli with black edging. The new species can be distinguished from its congeners on the basis of the following morphological attributes: a medium-sized lacertid lizard, maximum snout-vent length (SVL) = 64.5 mm, tail being ca. 1.5 times longer than body length (SVL), hindlimbs relatively long (hindlimb length to SVL ratio 0.46); subocular scale not reaching mouth edge, in touch with 6–8 supralabials; males with bright coloration consisting of 2–3 dorsolateral rows of light-colored ocelli with thick black edging; the ventral row of ocelli in life is greenish to bluish; dorsal pattern consisting of black irregular blotches along the middorsal line. We also report on the high genetic and morphological diversity of E. multiocellata in Mongolia and China, synonymize E. m. bannikowi with the nominative form E. m. multiocellata , discuss variation within E. przewalskii , synonymize E. p. tuvensis with the nominative form E. przewalskii , provide new data on E. cf. reticulata and E. m . tsaganbogdensis , confirm validity and clarify distribution ranges of E. stummeri , E. szczerbaki and E. yarkandensis and discuss further progress on taxonomic studies of the E. multiocellata—E. przewalskii species complex.

A new species of the genus Hemiphyllodactylus is described from Huishui County, Guizhou Province, Southwest China. Hemiphyllodactylus huishuiensis sp. nov. is distinguished from all other congeners by having the unique combination of the following characters: a maximum SVL of 51.2 mm; 8 or 10 chin scales; enlarged postmental scales; 3 circumnasal scales; 2 or 3 scales between the supranasals; 9–11 supralabials; 9–11 infralabials; 13–15 dorsal scales; 7–9 ventral scales; a lamellar hand formula of 3-4-4-4 or 4-4/5-5-4; a lamellar foot formula of 4-4/5-5-4/5; 3 subdigital lamellae on the first finger and first toe; a continuous precloacal and femoral pore series of less than 20; one cloacal spur in both males and females; no enlarged subcaudal scales; dark dorsal transverse blotches; dark postorbital stripe; a brown postsacral mark bearing anteriorly projecting arms; and unpigmented caecum and gonads. The new species also occurs in Ziyun County, Guizhou Province, China.

A new species of the genus Hemiphyllodactylus is described from mountainous area of Changning County, Yunnan Province, China. Hemiphyllodactylus changningensis sp. nov. is distinguished from all other congeners by morphology and a significant genetic divergence of greater than 17% (ND2 gene). The new species from Changning is characterized by the following features: a maximum SVL of 40.1 mm in males and 43.8 mm in females; 11-15 dorsal scale rows; 6-8 ventral scale rows; a forefoot lamellar formula of 3-3/4-3/4-3; a hindfoot lamellar formula of 3-4-4-4 or 3-3-3-3; precloacal and femoral pore series continuous; cloacal spurs present in both sexes; dark dorsal transverse blotches; dark postorbital stripe; a brown postsacral mark bearing anteriorly projecting arms; and unpigmented caecum and gonads. The new species occurs also in Longyang District of Baoshan City, Yunnan Province, China.

Non-random female mating preferences may contribute to the maintenance of phenotypic variation in color polymorphic species. However, the effect of female preference depends on the types of male traits used as signals by receptive females. If preference signals derive from discrete male traits (i.e., morph-specific), female preferences may rapidly fix to a morph. However, female preference signals may also include condition-dependent male traits. In this scenario, female preference may differ depending on the social context (i.e., male morph availability). Male tree lizards (Urosaurus ornatus) exhibit a dewlap color polymorphism that covaries with mating behavior. Blue morph males are aggressive and defend territories, yellow males are less aggressive and defend smaller territories, and orange males are typically nomadic. Female U. ornatus are also polymorphic in dewlap color, but the covariation between dewlap color and female behavior is unknown. We performed an experiment to determine how female mate choice depends on the visual and chemical signals produced by males. We also tested whether female morphs differ in their preferences for these signals. Female preferences involved both male dewlap color and size of the ventral color patch. However, the female morphs responded to these signals differently and depended on the choice between the types of male morphs. Our experiment revealed that females may be capable of distinguishing among the male morphs using chemical signals alone. Yellow females exhibit preferences based on both chemical and visual signals, which may be a strategy to avoid ultra-dominant males. In contrast, orange females may prefer dominant males. We conclude that female U. ornatus morphs differ in mating behavior. Our findings also provide evidence for a chemical polymorphism among male lizards in femoral pore secretions.

We describe the third new species of the genus Cyrtodactylus from Ba Den Mountain, Tay Ninh Province, southern Vietnam based on a type series consisting of eleven specimens. Cyrtodactylus thuongae sp. nov. is distinguished from the remaining Indochinese Bent-toed Geckos by a combination of the following morphological characters: size medium, with a maximum SVL of 77.6 mm; dorsal pattern consisting of blotches between limbs and on occiput and a sometimes medially opened nuchal loop; dorsal tubercles in 16-18 irregular rows; ventrals in 29-44 longitudinal rows at midbody; lateral skin folds present, lacking tubercles; femoral pore series separated from precloacal pore series in males, 0-3 on each side; precloacal pores in males absent or only one; enlarged femoral scales and precloacal scales present, separated by a series of 15-16 smaller scales; postcloacal spurs two or three; subcaudal scales slightly enlarged. This is the 32nd described Cyrtodactylus species from Vietnam.

Two new species of the gekkonid lizard genus Cyrtodactylus Gray, C. tigroides, sp. nov. and C. chanhomeae, sp. nov. are described on the basis of material collected in Kanchanaburi and Saraburi provinces, bringing the number of species of this genus in Thailand to 14. Both species have relatively slender bodies and elongate tails, limbs and digits. They differ significantly, however, with respect to precloacal and femoral pore arrangement and color pattern. They share a common habitus with the recently described C. sumonthai Bauer et al., which may reflect a close relationship or a similar limestone outcrop and cave dwelling ecology.