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The basic anatomy of the lacertid hemipenis (intromittent organ) and methods for its investigation are described. In many members of the Lacertidae, the hemipenis has a structure quite unlike that of other squamate reptiles: the distal lobes of the retracted organ are complexly folded and there is a well-defined supporting structure of dense connective tissue, the armature. This incorporates blood sinuses and has an intramuscular portion embedded in the m. retractor penis magnus and two club-shaped bodies, the clavulae, that support the lobes in the erect organ. Unarmatured hemipenes occur in some lacertids and, like those of other squamates, possess sac-like lobes in the retracted state, but they are singular in having the lobes invested by the m. retractor penis magnus. It is argued that many of these apparently primitive hemipenes are in fact secondary derivatives of the armatured type. There is considerable inter-specific variation in hemipenial structure which is described systematically. In some cases this involves differences in size, asymmetry and simplification, which may arise as physical isolating mechanisms and is useful in distinguishing otherwise very similar species, particularly in the genus Mesalina (p. 1253). Other shared derived hemipenial features provide useful information about relationships between species and higher taxa and a summary of the hypotheses that they support is given (p. 1254).

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The east Asian lacertid lizard genus, Takydromus, is well-defined but its relationships to other primitive Palaearctic lacertids are still uncertain and, although it has similarities to the lower Miocene Miolacerta. Takydromus does not appear to be identical with this. The 16 or 17 recognizable species are reviewed and a key provided for their identification; the remaining area of uncertainty about species boundaries is the Takydromus sexlineatus group in Assam. A phylogeny for Takydromus is estimated using a data set of 35 morphological characters drawn from external features, skeleton and soft-parts. There are two main constituent clades which may be informally recognized as Takydromus s.s. and Platyplacopus. Platyplacopus is subtropical and perhaps relict, whereas Takydromus ranges from temperature to tropical areas. The two clades have different ranges of eggs per clutch. In both of them, elongate forms that climb-extensively in flimsy vegetation have evolved and have independently acquired similar features that confer performance advantages in this situation. Interestingly, the order of assembly of these features is markedly different.

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DNA sequence indicates the Lacertidae contain two subfamilies, Gallotiinae and Lacertinae, the latter comprising two monophyletic tribes, the Eremiadini of Africa and arid southwest and central Asia, and the Lacertini of Europe, northwest Africa and southwest and east Asia. Relationships within the 108 species of Lacertini are explored using mtDNA (291 bp cytochrome b; 329 bp 12S rRNA for 59 nominal species, and reanalysis of the data of Harris et al. 1998, and Fu 2000). The morphology of the tribe is reviewed and 64 of its characters (equivalent to 83 binary ones) also used to assess relationships. The Lacertini are assigned to 19 monophyletic units of 1 to 27 species, recognised here as the following genera (contents are indicated in brackets): Algyroides, Anatololacerta gen. nov. (L. danfordi group), Apathya (L. cappadocica group), Archaeolacerta (L. bedriagae), Dalmatolacerta gen. nov. (L. oxycephala), Darevskia (L. saxicola group), Dinarolacerta gen. nov. (L. mosorensis), Hellenolacerta gen. nov. (L. graeca), Iberolacerta (L. monticola group), Iranolacerta gen. nov. (L. brandtii and L. zagrosica), Lacerta s. str. (sand and green lizards, L. agilis group), Parvilacerta gen. nov. (L. parva and L. fraasii), Phoenicolacerta gen. nov. (L. laevis group), Podarcis (wall lizards), Scelarcis (L. perspicillata), Takydromus (Asian grass lizards), Teira (L. dugesii), Timon (ocellated lizards, L. lepida group) and Zootoca (L. vivipara). Both mtDNA and morphology indicate that Lacerta and Timon are sister taxa, and DNA suggests further possible relationships among genera (Fig. 1, p. 6). Neither DNA nor morphology indicates that the archaeolacertas (sometimes formalised as Archaeolacerta sens. lat.) form a clade. Instead, they are representatives of an ecomorph associated with living on rock exposures and using the narrow crevices that these contain. The Lacertidae probably arose in the European area, with the Gallotiinae later reaching Northwest Africa and the Canary Islands, and the ancestor of the Eremiadini invading Africa in the mid-Miocene. The Lacertini spread through much of their present European range and diversified, perhaps largely by repeated vicariance, around 12–16 My ago, producing the ancestors of the present mainly small-bodied genera, which then underwent often modest speciation. Three units spread more widely: the Lacerta-Timon clade of large-bodied lizards probably dispersed earliest, followed by Algyroides and then Podarcis. Overall, European Lacertidae show a pattern of repeated spread, often accompanied by restriction of previous groups. Expansion of Lacertini may have displaced earlier lacertid lineages from all or much of Europe; while spread of Podarcis may have restricted many other genera of Lacertini. The earlier expansion of the Lacerta-Timon clade probably did not have this effect, as difference in adult body size restricted competitive interaction with other forms. Several invasions of more distant areas also occurred: of East Asia by Takydromus over 10 My ago, and more recently of northwest Africa by Podarcis, Scelarcis and Timon, and Madeira by Teira. Relationships within the Eremiadini estimated from both mtDNA, and nDNA differ considerably from those based on morphology. They indicate relatively mesic forms may have diversified widely across Africa and given rise to at least three independent invasions of arid habitats. MtDNA also indicates that Lacerta andreanskyi belongs in the Eremiadini and may occupy a basal position there. It is assigned to a further new genus, Atlantolacerta gen. nov.

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A complete catalogue is provided for the type specimens of lacertid lizards in the herpetological collection of the Zoological Museum, Berlin, as of December, 1993. The collection contains a total of 514 type specimens, representing 63 taxa, of which 42 are currently regarded as valid at the specific or subspecific level. Types representing an additional four taxa appear to have been lost from the collection. The collections are especially rich in African lacertid types and in historically significant specimens collected early in the Nineteenth Century by Pallas, Eversmann, and Hemprich & Ehrenberg. Also present are the type series of many subspecies of Podarcis lilfordi and P. pityusensis described by Eisentraut.

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Helminths from Eumeces latiscutatus (n = 17) and Takydromus tachydromoides (n = 34) from Japan are reported. Two species of Nematoda, Kurilonema markovi and Meteterakis japonica, and 1 taxon of Acanthocephala, cystacanths of Centrorhynchus sp., were found in E. latiscutatus; 1 species of Digenea, Plagiorchis taiwanensis, and 2 species of Nematoda, K. markovi and Oswaldocruzia filiformis, were found in T. tachydromoides. Oswaldocruzia yezoensis is proposed as a synonym of Oswaldocruzia filiformis. Takydromus tachydromoides represents a new host record for P. taiwanensis and Japan is a new locality record.

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The present paper attempts to elucidate the taxonomic status of five species of Takydromus (T. amurensis, T. wolteri, T. tachydromoides oldi, T. kwagakunesis and T. auroralis) reported in Korean Peninsula to date. For this purpose 114 Takydromus specimens were collected from April 2003 to october 2004 in Southern Korean peninsula and morphological characters inclusive of the presence of contact between front-nasal and fostral and the number of femoral pores have been analyzed. The analysis reveals that T. kwagakunesis and T. auroralis should be synonymized to T. amurensis. In addition, the Korean Takydromus consists of two species of T. amurensis and T. wolteri.

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Cytochrome b (cyt b) gene complete sequences (1143bp) of Takydromus sylvaticus were sequenced. In order to clarify the phylogenetic position of the Takydromus sylvaticus, we investigated the phylogeny of 15 Takydromus spp. distributed in East-Asia by Maximum Parsimony (MP), Bayesian Inference (BI), and Maximum Likelihood (ML) methods using DNA fragments of cyt b genes. The results supported that the Platyplacopus merged into Takydromus and negated the validity of Platyplacopus. Furthermore, the prediction of tertiary structures of cyt b exhibited the CD loop region contain two short helices forming a hairpin arrangement, namely cd1 and cd2. Thermostability analysis shows that the CD-loop region is unstable thermodynamically and may provide mobility to amino acids located at the heme, and might provide high flexibility to the top of ISP (iron–sulfur protein) and the cavity region of Qo binding site. It suggested that the two short helices of CD loop region of cyt b was a dominating portion for ISP binding site.

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The feeding and development of Amblyomma testudinarium Koch larvae on the lizard, Takydromus tachydromoides (Schlegel) were observed at 24℃ under a 16L-8D photoperiod and compared with those of the larvae on mice. The mean feeding periods of the larvae were 13.7 and 5.4 days on the lizards and the mice, respectively. The mean feeding period on the lizards was significantly longer than that on the mice. However, the molting success of the engorged larvae was 97% or more on both hosts. The mean developmental periods of the engorged larvae were 22.4 and 22.6 days on the lizards and the mice, respectively. The difference in the mean developmental period between the two hosts was not significant, suggesting that the difference in the host suitability between the two hosts is slight. Thus, the reasons why the immature ticks of A. testudinarium infest more frequently on mammals than on reptiles can not be explained by the difference in the host suitability between the cold-blooded and warm-blooded animals.

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The Japanese lacertid lizard Takydromus tachydromoides and the praying mantis Tenodera aridifolia are sympatric generalist predators feeding on similar prey. To confirm reciprocal predation between them, we observed the behavioural interactions between the lizards and the mantises of different sizes in a laboratory condition. The lizards caught small mantises (from first to fifth instars), but sometimes escaped from large mantises (from sixth instar to adult). Large mantises occasionally showed catch responses to the lizards. The lizards sometimes caught the mantis without a tongue-flick response (sampling of chemical cues), and they sometimes did not catch the small mantises showing immobile or cryptic responses that prevent visual detection. These results suggested the primary role of vision on recognition of the mantis as a prey. The lizards spent a longer time to approach larger mantises. The time from orienting to catch was longer when the lizards showed tongue-flick responses. The lizard also spent a longer time before deciding to escape from the mantis than to catch it. Biological significance of these differences in timing was discussed.

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It is important to investigate visual orienting in reptiles to better understand the basic organization of the oculomotor system in vertebrates. However, quantitative analyses of visual orienting behavior in reptiles have rarely been conducted, except in chameleons. In the present study, we videorecorded the head and body movements of the lizard Takydromus tachydromoides during visual tracking of moving prey and analyzed them frame-by-frame. Before approaching prey, visual tracking mainly consisted of brief intermittent turns of the head (saccade). After the head saccades, the angular position of the prey relative to the lizard head was kept at 10–70° (laterally) in most cases, rather than at 0° (in front). In addition, the ratio of the amplitude of the head saccades to prey position was 0.2–0.3, which is much smaller than 1, suggesting that the head did not orient exactly toward the prey after most saccades. These results were observed under both white (homogeneous) and grating (structured) backgrounds. Possible functions of head saccades in the lizard are discussed.

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Karyotype data are presented for 12 species of lacertid lizards. Of these, 4 Acanthodactylus, 2 Eremias, 1 Ophisops, and 4 Lacerta have n = 19, with all chromosomes acrocentric. This is the typical lacertid karyotype, as reported in previous literature. One species, Lacerta parva, is quite different from all the others. The haploid number is 12, consisting of 7 pairs of metacentric macrochromosomes and 5 pairs of microchromosomes. The fundamental number (number of arms in the karyotype) is the same in L. parva as in all the other species studied. The possibility of female sex chromosomal heteromorphism is raised, but data are not sufficient to confirm this.

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Scanning electron microscopy was employed to investigate the ultrastructure of oral epithelialcells of the lizard, Takydromus tachydromoides. The specimens were prepared by a methodinvolving osmium postfixation and acid treatment to remove extracellular attached material. Bump-shaped protuberances were arranged symmetrically on both sides of the median line of thepalate. Epithelial surfaces besides the bump-shaped protuberances were widely covered with fine folds.At higher magnification, a network pattern of microridges was closely distributed over the entiresurface of the palate, and each cell marginal thickening was clear. The protuberances were alsoobserved in the latero-posterior region of the floor of the mouth. A number of nicks were arrangedsymmetrically on both sides along the median line of the fore-region of the floor. Taste buds werescattered in the epithelial surfaces between nicks. At higher magnification, microvilli as well as microridgeswere observed on the epithelial cell surfaces of the floor. There were no papillar structures onthe ventral tongue surface. Fine pits were densely distributed over the entire epithelial cellsurface. The cell margin was clearly distinguishable as a depressed line. The epithelial surface ofthe laryngeal part of the pharynx was entirely covered with ciliated cells. Taste buds were alsoscattered on the inner gingival epithelial surfaces of the upper and lower jaws along the dentalarches. Relatively indistinct microridges were widely distributed on the gingival epithelial cell surfaceof the upper jaw. Scrollwork and network patterns of microridges were clearly observed on the gin -gival epithelial surface of the lower jaw.

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The Japanese lacertid Takydromus tachydromoides is an opportunistic, generalized predator; its diet consists chiefly of spiders and insects although other small arthropods and gastropods may be taken. Prey are lognormally distributed by size. Age-, season- and habitat-specific dietary differences are intimately related to the habits of this species. Such differences occur primarily in response to prey densities and are of adaptive value to the lizards. Most prominent among these differences is the ratio of insects to spiders in the diet. Competition between adult and juvenile lizards is reduced through partial nonoverlap of food resources and structural habitats. Takydromus displays certain aspects of predation recognized in the past predominantly from larger and better-known mammalian and reptilian carnivores. As a predator Takydromus probably exerts little limiting influence on its prey.

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The prey recognition system in the predatory behavior of T. tachydromoides was analyzed experimentally using unpalatabe Pryeria moths and edible mealworms. None of the Pryeria moths were either killed or eaten, while all the mealworms attacked were eaten. The learning of visual avoidance by T. tachydromoides, in which the lizard associates the unpalatability of Pryeria moth with its appearance and avoids it, seemed to exist, but its process appeared to be very slow. In the course of predatory behavior, the lizard first recognized the prey visually, but then checked it strictly through chemical cues. This suggested that not only visual but also other sensory cues such as olfactory and gustatory stimuli derived from the prey were necessary for the efficient avoidance learning in this lizard.

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We sequenced the mitochondrial genome of the Western green lizard (Lacerta bilineata) using Illumina technology and additional Sanger sequencing. The assembled 17 086 bp mitogenome had a GC content of 40.32% and consisted of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one control region (CR), with a gene order identical to the chordate consensus. In addition, we re-sequenced the mitogenome of the closely related Eastern green lizard L. viridis using the same techniques as for L. bilineata. The mitogenomes of L. bilineata and L. viridis showed a sequence identity of 94.4% and 99.9%, respectively, relative to the previously published L. viridis mitogenome. The phylogenetic reconstruction based on 17 Lacertinae mitogenomes using Anolis carolinensis as the outgroup supported L. bilineata and its sister species L. viridis as distinct lineages.

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Brown and green are the most commonly imitated colors in prey animals because both colors occur in a range of habitats. Many researchers have evaluated survival with respect to background color matching, but the pigment cell mechanisms underlying such coloration are not known. Dorsal coloration of East Asian Takydromus lizards has shifted from green to brown or from brown to green on multiple occasions during the diversification of the genus, thus giving us an opportunity to examine the cellular mechanisms of background color matching. Brown and green skin were found to differ with respect to the morphological characteristics of iridophores, with different thicknesses of the reflecting platelets and the cytoplasmic spacing between platelets, despite a shared vertical arrangement of pigment cells, i.e., xanthophores in the upper layer, iridophores in the middle layer, and melanophores at the bottom of the dermal layer, among the different Takydromus lizards. Iridophores of brown skin reflected longer wavelengths of light than those of green skin, which may be attributed to the thicker platelets and longer distances between platelets in brown skin. We discuss the potential role of genetic and intracellular mechanisms explaining the thickness and orientation of the light-reflecting platelets of iridophores in Takydromus lizards.

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Takydromus Daudin is a group of Lacertidae lizards with slender bodies and long tails. Half of the Takydromus spp. are endemic to islands of eastern Asia aligned along the Pacific margin of the East Asian continent. This feature offers a good opportunity to study the effects of glaciations and land connections on the speciation of East Asian fauna. We reconstructed the molecular phylogeny of Takydromus species via the mitochondrial 12S rRNA gene. Phylogenetic analyses using maximum-parsimony, neighborjoining, and maximum-likelihood options do not support a two-subgenera scheme of Takydromus and Platyplacopus proposed earlier. In contrast, the phylogeny of Takydromus species on islands fits the sequential separation of island groups influenced by changes in sea level. The hypothesis in our prediction supports the process of vicariant speciation and multicolonization of grass lizards on eastern Asian islands. At least two obvious colonization events were followed by vicariance events. Because the molecular clock of the 12 rRNA gene was not rejected in our model test, it is possible to estimate times of speciation events. As the most isolated and basal species compared to other temperate and subtropical species of Takydromus, the separation period of T. smaragdinus in the central Ryukyus is the crucial point in estimating the evolutionary rate. Quaternary-origin or Tertiary-origin models are proposed and discussed

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Two new grass lizard species, previously confused with Takydromus formosanus, were identified in Taiwan using mitochondrial DNA sequences. In the present study, 40 morphological characters and their taxonomic significances were assessed using principal components analysis and discriminant analysis. The three species can be distinguished by morphology of body sizes, dorsal and caudal scales, and most importantly, by male coloration during the breeding seasons. The present study increases the total number of Takydromus to 19 species, of which 10 are insular endemics, with six only occurring in Taiwan.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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Thermal reaction norms of sprint speed were examined in three lacertid lizard species (Takydromus tachydromoides, T. smaragdinus, and T. dorsalis). We found inter- and intraspecific variations in maximum sprint speed, optimal body temperature, and thermal performance breadth for the best sprints. The thermal performance breadth of T. smaragdinus was broader than that of T. tachydromoides or T. dorsalis, whereas T. dorsalis sprinted faster than the others. In T. smaragdinus, individuals with narrower performance breadths run faster within their thermal range of expertise. There were “specialist” individuals of which performance depended heavily on high temperatures, as well as “generalist” individuals that performed well over a broad range of temperatures even within a single population. We discussed that the spatiotemporal instability of habitats might favor more than one type of thermal reaction norm of sprint performance, and this phenomenon may be driven by specialist–generalist trade-offs.

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Behavioral responses of the Japanese lacertid lizard,Takydromus tachydromoides, to its natural predator, the Japanese striped snake,Elaphe quadrivirgata, were examined under laboratory conditions.T. tachydromoides often thrashed its tail rapidly from side to side for short intervals (less than 0.5 s), usually just before fleeing away from an approaching snake. This tail vibration behavior appears to distract the snake away from the vulnerabl parts of the body to the tail, as tail vibration occurred more frequently when the head of the snake was closer to the lizard`s head than its tail. Distraction of snake attack by this action is suggested to be an antipredator tactic, because it was demonstrated that the vibration increased the chance of escape.

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Frequencies of movement, as an index of propensity for immobility, of Takydromus tachydromoides were measured in the encounters with a potential predator Elaphe quadrivirgata (Session A) or a sympatric non-predator Eumeces latiscutatus (Session B), or in the absence of other animals (Session C). Frequency of movement in Session A was significantly lower than in Sessions B and C. In Session B, T. tachydromoides moved significantly less frequently during the first 10min than during the latter 10min. The lizards previously exposed to E. quadrivirgata reduced their movements in the subsequent Session B with significantly high frequency when compared with animals without such experience. It is suggested that immobility of T. tachydromoides is an adaptive antipredator behavior to avoid detection by a visually orienting predator.

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Animals possess systems for sensing environmental temperature using temperature-sensitive ion channels called transient receptor potential channels (TRPs). Various TRPs have been identified and characterized in mammals. However, those of ectotherms, such as reptiles, are less well studied. Here, we identify the V subfamily of TRP (TRPV) in two reptile species: Japanese grass lizard (Takydromus tachydromoides) and Japanese four-lined ratsnake (Elaphe quadrivirgata). Phylogenetic analysis of TRPVs indicated that ectothermic reptilian TRPVs are more similar to those of endothermic chicken and mammals, than to other ectotherms, such as frog and fish. Expression analysis of TRPV4 mRNA in the lizard showed that its expression in tissues and organs is specifically controlled in cold environments and hibernation. The mRNA was ubiquitously expressed in seven tissues/organs examined. Both cold-treatment and hibernation lowered TRPV4 expression, but in a tissue/organ-specific manner. Cold-treatment reduced TRPV4 expression in tongue and muscle, while in hibernation it was reduced more widely in brain, tongue, heart, lung, and muscle. Interestingly, however, levels of TRPV4 mRNA in the skin remained unaffected after entering hibernation and cold-treatment, implying that TRPV4 in the skin may act as an environmental temperature sensor throughout the reptilian life cycle, including hibernation. This is the first report, to our knowledge, to describe reptilian TRPV4 in relation to hibernation.

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Two exampls of double-tailed lizards, Takydromus tachydromoides SCHLEGEL and Anolis c. carolinensis, were examined. The Takydromus possessed a normally regenerated tail laterally, and an abnormally regenerated tail ventrally. X-ray photography showed the 38th vertebra bent ventrally at an angle of 90. Both the vertebra and the core of the ventral tail stained red with Mall`s Arizalin red-S, indicating that the core was formed of cartilage, or chondrin, or cartilagious tissue. This tail is presumed to have arisen from a broken bone. The regenerated tail of the Anolis was normal, without any Vertebrae.

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A morphological study on the monstered tail of two species of Lacertilia was done with X-ray photograph and Mall`s alizalin red-S staining method. One of them, Gekko japonicus, has a forked tail, and the other one, Takydromus tachydromoides, has a triple tail. The former`s regenerated tail develops at the level of the left transverse process of the 50th vertebra. It shows normal feature in structure. The latter`s primary regenerated tail develops at the caudal part of the 33rd vertebra and the secondary re- generated tail develops at the middle part of the primary regenerated tail. It seems to be constituted with cartilage or chondrin. These specimen were collected in Aichi Prefecture.

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A study of 3 spp. of the Lacertidae showed the chromosome number of Takydromus tachydromoides and T. smaragdinus as 2N = 38, each sp. having a pair of m-chromosomes of minute size; and of Lacerta vivipara as 2N = 36 with no m-chromosomes. A single specimen of T. smaragdinus possessed exceptionally large m-chromosomes, whereas they were of medium size in other specimens and extremely small in T. tachydromoides. Evidence of diminution in the size of the m-chromosomes by species and the assumption of their final disappearance may explain the numerical relation of the chromosomes found in Takydromus and L. vivipara.

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In 1967, the author conducted a herpetolog cal survey of the islands of Niijima, Shikinejima, and Kozushima, which belong to the Izu island chain of Japan. The harpetological fauna of thes islands is very poor, and no amphibians occur, but the author confirmed the occurrence of 4 species of reptiles belonging to 3 families, as listed below. Colubridae 1. Elaphe quadrivirgata (Boie, 1826) (Niijima, Kozushima). 2. Elaphe climacophora (Boie, 1826) (Niijima, Kozushima). Scincdae 3. Eumeces okadae Stejneger, 1907 (Niijima, Shikinejima, Kozushima). Lacertidae 4. Takydromus tachydromoides (Schlegel, 1838) (Kozushima).

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The fine structure and immunocytochemical localization of serotonin in the cells of the receptor line were studied in the parietal eye and pineal organ proper of the Japanese grass lizard, Takydromus tachydromoides. Typical photoreceptor cells (PC) were the predominant cell type in the receptor line of the parietal eye, the outer segments of which had regular stacks of numerous disks similar to those of cones. The pineal organ contained relatively few PCs, which showed less well-developed outer segments than those of the parietal eye. In contrast, rudimentary photoreceptor cells (SRPC) accounted for the majority of receptor cells in the pineal organ. These cells were structurally characterized by whorl-like lamellar outer segments and numerous dense-cored vesicles (80–280 nm in diameter). A small number of SRPC were also found in the parietal retina, which were similar to those in the pineal organ. In the parietal–pineal complex, numerous mitochondria located in the PC were larger and rounder than those in the SRPC. In the PC, basal processes prossessed only synaptic ribbons, whereas in the SRPC some of these processes contained synaptic ribbons and others contained dense-cored vesicles, rarely having both. Serotonin-immunoreactive cells were found not only in the pineal organ but also in the parietal eye, which closely resembled the cells of the receptor line in their size and shape. Furthermore, on immunoelectron microscopy for serotonin using the protein A-gold technique, gold particles indicating serotonin-immunoreactive sites were restricted in the core of dense-cored vesicles in the SRPC of the pineal organ. Regional differences in the distributions of the PC, SRPC and serotonin-immunoreactivity were found in the parietal-pineal complex.

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The Japanese grass lizard, Takydromus tachydromoides, is a species endemic to Japan. While several studies have investigated the reproductive ecology of T. tachydromoides, the embryogenesis of this species has not been reported in detail. In the current study, we observed the external morphological characteristics of 247 embryo specimens that developed under a constant temperature (28°C) throughout the duration from oviposition to hatching. We identified 17 consecutive developmental stages for the postovipositional developmental process of this species based on the staging criteria that have been widely used for the description of embryogenesis of lizards. The youngest embryos on the day of oviposition corresponded to stage 26, which is a relatively early period in pharyngula stages, and juveniles hatched at stage 42, approximately 30 days after oviposition. The entire developmental sequence of key morphological features was shared with other species of Lacertidae, except for the timing of the beginning of the first body pigmentation. This is the first description of the complete sequence of postovipositional developmental stages for the oviparous species of Lacertidae, providing valuable information for further evolutionary developmental studies.

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Squamate reptiles rely on the vomeronasal organ for chemoperception of their environment. This organ functionally associates with several structures, such as the nasolacrimal duct and choanal groove, which are morphologically diverse among species. In this study, we investigated the morphological characteristics and embryogenesis of the vomeronasal organ and its associated structures in the Japanese Grass Lizard (Takydromus tachydromoides). Separation of the complex of the nasolacrimal duct from the vomeronasal organ was observed in this species, a characteristic morphological feature among squamates. Additionally, we integrated the morphological characteristics of the vomeronasal organ and associated structures among squamates, focusing on topological relationships among the structures. The parsimony and likelihood methods for ancestral state reconstruction suggested the parallelism of several morphological characteristics during the evolutionary history of squamates: loss or reduction of the choanal groove, fusion between the nasolacrimal duct and choanal groove, and separation of the nasolacrimal duct from the vomeronasal organ.

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Historical relationships were inferred for the oriental lizards of the genus Takydromus Daudin 1802 (Lacertidae) on the basis of DNA sequences. Of the 17 species currently recognized for the genus, 13 species represented by 42 specimens from 29 localities were examined. Maximum-likelihood and maximum-parsimony analyses of data for 829 aligned sites from parts of the mitochondrial 12S and 16S rRNA genes yielded relationships that, while showing no substantial discrepancy with each other, were strikingly different from a currently prevailing phylogenetic hypothesis from a parsimony analysis of morphological characters. Based on the results of these molecular analyses, supplemented by results of the morphological analysis that offered robust evidence for positions of two additional species (T. khasiensis and T. sylvaticus), the following interrelationships were hypothesized as the most preferred phylogeny: (kuehnei (sexlineatus khasiensis))(tachydromoides ((smaragdinus (sauteri (dorsalis sylvaticus))) (amurensis (((formosanus wolteri) hsuehshanensis)(toyamai (septentrionalis stejnegeri)))))). These interrelationships indicate: (1) invalidity of Platyplacopus Boulenger 1917, which was recently resurrected as a subgenus of Takydromus on the basis of the morphological analysis; (2) homoplasy in states of some morphological characters, such as green dorsal coloration, that were considered as synapomorphs of certain nodes in the morphological analysis; and (3) involvement of the genus in a series of vicariances in both the continental and insular parts of eastern Eurasia. Due to the paucity of available samples, phylogenetic status of T. intermedius and T. haughtonianus remain to be examined in future studies.

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Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.

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The area traversed by an animal during food gathering, mating, and other routine activities is termed the home range (HR), and its size is believed to reflect behavioral and physiological requirements (e.g., access to mates and food). We evaluated both biological and methodological factors that may affect estimated HR sizes of lizards. We compiled a database of nearly 500 published sex 3 population data sets. These yielded usable data for 108 populations from 60 species, all with both sexes represented. Initial analyses indicated pervasive sex differences, so sexes were analyzed separately with both conventional and phylogenetically based statistical methods. First, we conducted conventional analyses of covariance, which treat each data point as statistically independent. Second, we repeated these analyses while comparing members of two major clades represented in our database, Iguania and Autarchoglossa. Third, we repeated the analyses after designating smaller clades, nested within major clades. Fourth, we performed a fully phylogenetic analysis via independent contrasts and a composite phylogeny assembled from published studies. All analyses showed highly significant effects of both biological (body size, diet, habitat type) and most methodological (calculation method and minimum number of sightings per individual, but not study duration) factors and covariates tested. The conventional analysis comparing Iguania and Autarchoglossa en toto indicated a significant difference, as has been suggested in the literature. The analysis with nested minor clades, however, revealed differences among these but not between the two major clades. The analysis with phylogenetically independent contrasts indicated no statistically significant differences either among minor clades or between major clades. We also used our database to compare the scaling of HR area to body mass, using recently published allometric equations for field metabolic rates of lizards. The similarity of allometric slopes suggests that, interspecifically, HR size scales directly with energetic requirements. Intraspecifically, however, we found that males in both Autarchoglossa and Iguania consistently had larger HRs than did females. This difference, presumably related to the need to maximize access to females, may impose a ‘‘cost of reproduction’’ on males.

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The squamates are composed of many taxa, among which there is morphological variation in the vomeronasal organ (VNO). To elucidate the evolution of chemoreception in squamate reptiles, morphological data from the VNO from a variety of squamate species is required. In this study, the morphology of the VNO of the grass lizard Takydromus tachydromoides was examined using light and electron microscopy. The VNO consists of a pair of dome-shaped structures, which communicate with the oral cavity. There are no associated glandular structures. Microvilli are present on the apical surfaces of receptor cells in its sensory epithelium, as well as on supporting cells, and there are centrioles and ciliary precursor bodies on the dendrites. In addition to ciliated cells and basal cells in the non-sensory epithelium, there is a novel type of non-ciliated cell in T. tachydromoides. They have constricted apical cytoplasm and microvilli instead of cilia, and are sparsely distributed in the epithelium. Based on these results, the variation in the morphology of the VNO in scincomorpha, a representative squamate taxon, is discussed.

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We investigated the genetic population structure of the Japanese grass lizard, Takydromus tachydromoides, based on polymerase chain reaction—restriction fragment length polymorphisms (PCR-RFLPs) and DNA sequence analyses of the mitochondrial cytochrome b gene. The PCR-RFLP analysis of 163 specimens collected from the main islands of Japan and the adjacent islands identified a total of 25 mitochondrial haplotypes (mitotypes). The phylogeny of the mitotypes revealed that Osumi and Tokara Island populations were remarkably diverged from all other populations on the main islands of Japan. Furthermore, several regional groups were also recognized at the western part of Japan, namely mitotype groups in Kyushu, those in the western Honshu, and those in the central Honshu and Shikoku. In contrast, little genetic diversity was observed throughout eastern Japan. The regional genetic differentiation and recent range expansion of this species are considered to be associated with past geological events and climate changes.

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Growth of Takydromus tachydromoides was studied at Fukuoka in southwestern Japan. From the data of growth in SVL, the lizards were classified into three age classes. The growth rate of SVL did not differ between sexes. The mean body weight of adult lizards differed significantly between sexes, but SVL did not.

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The home range of Takydromus tachydromoides was studied in a grassland area from April 1977 to November 1978. The mean size of home range did not differ markedly between sexes; 136.5 m2 for males and 130.8 m2 for females. Home ranges of adults overlapped greatly in each sex, and the lizard was considered to be non-territorial. Individuals showed return movement to a definite area (sleeping site) within the home range, and the home range did not shift within a year or between years. Characteristics of the home range of this grassland-inhabiting lizard were discussed in relation to resource abundance and predation pressure.

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A field study of the Japanese grass lizard Takydromus tachydromoides was carried out at Mito in central Japan. The mean growth rate of yearling females was highest during late spring. They grew little during the reproductive season (mid-summer), but resumed growth somewhat in late summer. Most energy is apparently directed to body growth in yearling females before the first reproduction. Thereafter most energy is allocated to reproduction.

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Reproduction in females of the kanahebi lizard, Takydromus tachydromoides, was studied in Mito, Ibaraki Prefecture. Yearling females larger than 40mm SVL and not reproductive early in the reproductive season (April-May) might be judged to be mature because their largest unyolked follicles were the same size as those of reproductive females (1.3mm or larger). Most yearlings bred once or twice late in the reproductive season (June-July), and they had a mean clutch size of 3.0. Older females reproduced from April through July, and they had a mean clutch size of 4.2 for the first clutch and of 4.0 for the second and third. In this population the mean dry weight of oviducal eggs was 84mg, and the mean ratio of clutch weight to body weight was 0.729.

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Eimeria takydromi n. sp., a coccidian infecting the gall-bladder epithelium and bile-ducts, was found to parasitise three Takydromus species: T. tachydromoides of Honshu, Japan; T. smaragdinus of Amami Oshima, Ryukyu Islands, Japan; and T. sexlineatus of Thailand. Although differences were found in the mean oöcyst and sporocyst indices among the different hosts, the considerable overlap in morphometric characters demonstrated conspecificity. Eimeria takydromi is an addition to the symbiotic complex associated with Takydromus spp. in eastern and southeastern Asia that includes Plasmodium sasai, Trypanosoma takydromi, Schellackia sp. and Lizard Erythrocytic Virus. These host-symbiote associations may have persisted since a lacertid ancestral to the modern species of Takydromus dispersed throughout the region from the late Pliocene.

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A three year study of a population of Takydromus tachydromoides in central Honshu, Japan revealed that yolk deposition in follicles of juvenile lizards begins in the late spring following their first hibernation, at a body length exceeding 41 mm. Adult females emerge from hibernation with yolked follicles. Oviposition of first year lizards begins in early June, reaches a maximum in July and ends before mid-August. Older females begin oviposition in early May, reach their peak in the first half of June, and cease laying in late July. In experimental lizards corpora lutea regressed from an average of 2.1 mm on the day of oviposition to 1.0 mm five days postoviposition. These persist as corpora albicantia apparently for the life of the lizard. Estimates of age groupings by counts of corpora albicantia suggests that first year females contain none in spring and 4-13 in fall; second year lizards, 1-12 in spring and 14-26 in fall; third year females, 14-23 in spring and 26-39 in fall; and fourth year females, 31-40 in spring and 51-69 in fall. The incidence of corpora albicantia in adult lizards collected from 15 August until hibernation is 97%. Clutch size of first year lizards ranges from 1 to 4 for all clutches, with means of 2.6 for the first clutch and 2.4 for the second and third. Clutches of second year females range from 1 to 6, with means of 4.0 for the first and second, and 3.4 for the third clutch. Third year females lay clutches of 1-7 ova, with means of 4.4 and 5.1 for first and second clutches, respectively; third clutches approximate 3.5 eggs. Fourth year females apparently deposit 4-6 ova or more per clutch. Mean clutch number calculated by dividing average clutch size into the mean number of corpora albicantia in fall lizards is 2.9. A mean clutch number of 2.7 was obtained by dividing the length of the reproductive season by the time required to produce the first clutch. The reproductive season varied from 76 to 86 days for first year females, and from 112 to 127 days for older females. Reproductive potentials estimated by counts of yolked follicles, corpora lutea and oviductal eggs were 7.4, 11.4, and 12.8, for first, second and third year females, respectively. Estimated from the mean difference between counts of corpora albicantia in spring and fall lizards, they were 9.3, 12.9 and 11.6, in respective order. The latter method suggests a mean reproductive potential for fourth year females of 20.4. There is no difference in average clutch size between small and large females of the same age group, but second year females produce first clutches nearly twice as large as those of first year lizards. Average weights of individual eggs and total clutches increase as females age. Total clutch weight ranges from 30 to 50% of the females postovipositional weight. The sex ratio in all age groups in each season is 1:1. Of the total female sample, 62.5% had survived their first breeding season, 25.0% their second, 9.8% their third, and 2.7% their fourth season.

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easonal fluctuations in liver and fat body weights were studied in a population of Takydromus tachydromoides (Lacertidae) during two annual cycles. Liver and fat body weights are at minimum levels in late summer and rise rapidly in September and early October prior to hibernation. Livers of adult females and juveniles of both sexes show no apparent weight loss, but livers of adult males decrease in weight during hibernation, and continue to decline throughout spring and early summer. Livers of juvenile males and all females increase in weight during spring; those of adult females decrease during formation of clutches two and three in June and early July. Fat bodies of each age group of both sexes decrease in weight by approximately 50% during hibernation. Fat bodies of males continue to decline until July, although those of juvenile males increase immediately following hibernation. Adult and juvenile females increase fat reserves until vitellinogenesis for the first clutch increases sharply in the last half of April by adults and in late May by juveniles. Later clutches then exhaust remaining fat reserves. Fat bodies of adult females decreased in weight by 83 and 74% during formation of clutch one in 1966 and 1967. Age differences exist in proportionate organ weights of each sex during much of the season. During formation of clutch one, second year females had available approximately three times as much fat as did first year females.

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Three mantid species, Tenodera aridifolia (Stoll), Hierodura patellifera (Serville), and Statilia maculata Thunberg, of varying body size and habitats, exhibited defensive reactions when faced with a natural enemy, the Japanese skink, Takydromus tachydromoides (Schlegel). Defensive reactions were analyzed as primary or secondary defenses for all stages. Of the primary defenses, the cryptic reaction was the main defensive reaction: mantids lowered the prothorax and simultaneously stretched the prothoracic legs, the antennae were arranged forward, and the abdomen was sometimes extended posteriorly. The frequency of the subcryptic reaction as a primary defense tended to increase with more advanced developmental stage. The primary defensive strategy switched at specific developmental stage and also depended on the distance between the prey mantid and the natural enemy. In some instars, T. aridifolia and H. patellifera displayed the cryptic reaction when the mantid—foe distance was long, whereas they displayed the subcryptic reaction when the mantid—foe distance was short. However, S. maculata did not switch defense strategies based on the mantid—foe distance. The secondary defenses of young instar nymphs of T. aridifolia and H. patellifera were primarily defensive reactions, whereas the frequency of aggressive reactions tended to increase with developmental stage. S. maculata did not display aggressive reactions during any stage. We concluded that the primary and secondary defenses used by mantids depend on the developmental stage and mantid—foe distance. Moreover, three mantid species that vary in both body size and habitat showed different defensive reactions when faced with a natural enemy.

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The final-instar larvae of Pryeria sinica Moore, 1877 (Zygaenidae) are conspicuously colored yellow-green with black stripes and are known to escape from attacks after predators learn of the cyanogenic fluids secreted on their body surface. Ivela auripes (Butler, 1877) (Lymantriidae) is often found in the same habitat during the same season as P. sinica, and its pupa (not larva) is similar to larval P. sinica in shape and color. Mature larvae of P. sinica search for pupation sites during the daytime and pupate in cryptic, pale-brown cocoons. On the other hand, I. auripes pupates without cocoons on substrates near and above the ground, where they appear to be exposed to predators. In this study, it was observed that Japanese tits, Parus minor Temminck & Schlegel, 1848, ate I. auripes pupae attached to a wall, but no tit individual ever attacked them repeatedly. When fed pupae or larvae in the laboratory, Japanese grass lizards, Takydromus tachydromoides (Schlegel, 1838), rarely ate larval P. sinica or pupal I. auripes or regurgitated them soon after eating them, suggesting their unpalatability. If discrimination of pupal I. auripes from larval P. sinica is not precise for these potential predators, their similar warning colors might constitute a rare case of Müllerian mimicry between different developmental stages of unrelated moth species.

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Extraretinal photoreceptor cells have been found in the pineal complex and deep brain of a variety of non-mammalian vertebrates. Light signals received by these photoreceptor cells seem to be a potent regulator of diverse physiological responses. Here, the pineal complex and deep brain of the Japanese grass lizard, Takydromus tachydromoides, were immunohistochemically analyzed to localize the photoreceptive molecule (opsin) and the light signal-transducing G-protein (transducin). In addition to the pineal organ and parietal eye constituting the pineal complex, we unexpectedly found a parapineal organ, which is located just below the parietal eye and is morphologically similar to the pineal organ. Both organs had photoreceptor-like cells with outer segments immunostained by anti-rhodopsin and anti-pinopsin antibodies. Neither opsin- nor transducin-like immunoreactivities were detected in the parietal eye with all the antibodies tested in this study, although its morphology resembles that of the lateral eyes. In the deep brain region, rhodopsin-like immunoreactivities were observed in the posterior pallial commissure and median eminence. The cerebrospinal fluid-contacting neurons in the paraventricular organ were immunoreactive to an antibody against α-subunit of cone transducin. In lizards, this is the first report showing (1) rhodopsin- and pinopsinlike immunoreactivities in the parapineal organ, (2) rhodopsin-like immunoreactivity in the deep brain, and (3) putative photoreceptive areas in the hypothalamus.