Nove zoološke študije

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Ker nimam časa prevajati novosti, bom tu na hitro samo podal nekaj zanimivih novih naslovov zadnjih dni s področja teraristike. Tega je sicer veliko, škoda ker ne utegnemo vsega prebrati

Leache AD. 2009. Species Tree Discordance Traces to Phylogeographic Clade Boundaries in North American Fence Lizards (Sceloporus). Systematic Biology 58(6): 547-559.

San Mauro, Diego; David J. Gower, Tim Massingham, Mark Wilkinson, Rafael Zardoya and James A. Cotton. 2009. Experimental design in caecilian systematics: phylogenetic information of mitochondrial genomes and nuclear rag1. Systematic Biology 58: 425-438.

Townsend TM, Vieites DR, Glaw F, Vences M. 2009. Testing Species-Level Diversification Hypotheses in Madagascar: The Case of Microendemic Brookesia Leaf Chameleons. Systematic Biology 58(6): 641-656.

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Janzen FJ, Warner DA. 2009. Parent-offspring conflict and selection on egg size in turtles. Journal of Evolutionary Biology 22(11): 2222-2230.

http://www3.interscience.wiley.com/jour ... 1&SRETRY=0
Abstract
The trade-off between offspring size and number can present a conflict between parents and their offspring. Because egg size is constrained by clutch size, the optimal egg size for offspring fitness may not always be equivalent to that which maximizes parental fitness. We evaluated selection on egg size in three turtle species (Apalone mutica, Chelydra serpentina and Chrysemys picta) to determine if optimal egg sizes differ between offspring and their mothers. Although hatching success was generally greater for larger eggs, the strength and form of selection varied. In most cases, the egg size that maximized offspring fitness was greater than that which maximized maternal fitness. Consistent with optimality theory, mean egg sizes in the populations were more similar to the egg sizes that maximized maternal fitness, rather than offspring fitness. These results provide evidence that selection has maximized maternal fitness to achieve an optimal balance between egg size and number.


Mississippijska mehkoščitka, Apalone mutica, Le Sueur, 1827
Samica te vrste izleže 3-28 jajc maja ali junija.
Foto: Department of Wildlife Conservation, Oklahoma (photo credit: Suzanne L. Collins, CNAH)

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Marešová J, Landová E, Frynta D. 2009. What makes some species of milk snakes more attractive to humans than others? Theory in Biosciences 128(4): 227-235.
http://www.springerlink.com/content/c07x521g64435274/



Abstract
Animals are ancestrally important stimuli for humans who pay disproportional attention to animal objects and exhibit an outstanding ability to categorize animal species, especially those most relevant to them. Humans as well as other primates perceive snakes as ambivalent stimuli that elicit unspecific arousal and attention. We assessed human aesthetic preferences toward milk snakes, the traditional model for studies of Batesian mimicry. The genus is fairly uniform in size and shape, but includes a great variety of color forms; some possessing aposematic patterns while others being rather cryptic. This provides an opportunity to test which features are responsible for positive aesthetic evaluation of the species. We asked the respondents to rank 34 pictures of milk snakes according to perceived beauty. The sets (whole bodies, heads, and skin fragments) covered most of naturally occurring variation in milk snake appearance. While ranking the beauty, the respondents spontaneously classified the species according to two dimensions. In each set, one of the dimensions corresponds to perceived beauty. The respondents’ ranking revealed several distinct clusters of species instead of a continuous gradient. The species clustered in a similar way irrespective of evaluated set. One dimension of the ranking associated with the relative representation of red color and the number of transversal stripes, the other corresponded to a low proportion of red and a high proportion of black color. When the whole body of the snake is evaluated, aposematic coloration contributes to its perceived beauty. In conclusion, humans showed a surprising ability to classify milk snake patterns; they repeatedly formed the same distinct groups of species, thus completing a process that resembles unsupervised categorization.

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Nova vrsta legvana rodu Enyalioides.
Torres-Carvajal O, de Queiroz K, Etheridge R (2009) A new species of iguanid lizard (Hoplocercinae, Enyalioides) from southern Ecuador with a key to eastern Ecuadorian Enyalioides. ZooKeys 27: 59–71. doi:10.3897/zookeys.27.273

Abstract
We describe a new species of Enyalioides from mid-elevation rainforests in southeastern Ecuador. This represents the fifth species of Enyalioides known to occur east of the Andes in South America; the other four species are E. cofanorum, E. laticeps, E. microlepis and E. praestabilis. Among other characters, the new species can be distinguished from other Enyalioides by having distinct caudal whorls, fewer than 32 longitudinal rows of dorsals at midbody, and bright orange to red gular scales bordered with black in adult males. Morphological similarity suggests that the new species, which we call E. rubrigularis, is closely related to E. praestabilis.

Glava samca Enyalioides rubrigularis (QCAZ 8460).

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RÖSLER H, NGUYEN TQ, DOAN KV, HO CT, NGUYEN TT, ZIEGLER T. 2010. A new species of the genus Gekko Laurenti (Squamata: Sauria: Gekkonidae) from Vietnam with remarks on G. japonicus (Schlegel). Zootaxa 2329: 56-68.
Abstract[*]
We describe a new species of the gekkonid genus Gekko from northern Vietnam on the basis of four specimens from Lang Son and Lao Cai provinces. Gekko canhi sp. n. is distinguished from the remaining congeners by the combination of the following characters: body size moderate (SVL < 100 mm); supralabials 12–14, infralabials 10–13; nares in contact with rostral, internasal single, nasals 3; interorbitals 47–50; dorsal tubercle rows 10–13; scales between mental and cloacal slit 205–229; midbody scales 164–170; subdigital lamellae below first toe 13–16, below fourth toe 14–17; extensive webbing between fingers and toes minimal; tibial tubercles present; precloacal pores 5; postcloacal tubercles 2–3; tail round, not thickened at base; caudal tubercles present; subcaudals enlarged. We also provide new information on the taxonomy and distribution of G. japonicus in Vietnam.

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Dennis M. Hansen & Christine B. Müller - Invasive Ants Disrupt Gecko Pollination and Seed Dispersal of the Endangered Plant Roussea simplex in Mauritius - newscientist, 2008
ABSTRACT
In Mauritius, the endemic blue-tailed day-gecko Phelsuma cepediana is currently the sole pollinator and seed disperser of the critically endangered endemic plant Roussea simplex (Rousseaceae). The flowers and fruits are often visited by the invasive ant Technomyrmex albipes, which forages on the nectar and fruit pulp, and tends honeydew-producing mealybugs on the fruits. Here, we experimentally explore how the presence of this alien ant species influences geckos foraging at flowers and fruits of R. simplex by removing and excluding ants from flowers and fruits. Gecko visitation rates to ant-free control flowers and fruits, and flowers and fruits where ants had been removed and excluded, were higher than those to ant-infested flowers and fruits. The resulting seed set of ant-infested flowers was greatly reduced, compared to ant-free control flowers. Similarly, for fruits with ants, very few seeds were likely to be ingested and dispersed by the geckos. Thus, T. albipes monopolizes flowers and fruits of R. simplex, and prevents access of pollinating and seed-dispersing P. cepediana geckos by aggressive interference competition. For a critically endangered plant like R. simplex, this double-disruption of two vital mutualistic interactions is of urgent conservation concern.

Slika: Phelsuma cepediana foto © Dennis Hansen http://www.spektrumdirekt.de

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Shih L, Zhao H. 2010. A new species of Cyrtodactylus (Reptilia: Squamata: Geckkonidae) from Xizang Autonomous Region, China. Zootaxa 2336: 51-60.
Abstract
A new species of Cyrtodactylus described from Nyemo County, Xizang Autonomous Region, China is here referred to a new species, Cyrtodactylus zhaoermii sp. nov. It is distinguished from all other Cyrtodactylus by the following characters: dorsal surface of the body with fine granules intermixed with larger sub-conical tubercles arranged into 20 more or less regular rows; proximal subdigital lamellae transversely expanded; 19–20 subdigital lamellae on toe IV; 30–32 midbody ventral scales; most scales in femoral region small, granular, series of 12–14 enlarged femoral scales lacking pores; a series of precloacal pores (4) present in male; tail with distinct segments, large, posteriorly directed tubercles in whorls, numbering nine to ten per caudal annulus, three on each side and three to four on the dorsum, situated at the posterior edge of each annulus; subcaudals not transversely expanded. The new species is the fourth Cyrtodactylus known from Xizang Autonomous Region.

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Jacobson ER, Berry KH, Stacy B, Huzella LM, Kalasinsky VF, Fleetwood ML, Mense MG. 2009. Oxalosis in wild desert tortoises, Gopherus agassizii. Journal of Wildlife Diseases 45(4): 982-988.
Abstract
We necropsied a moribund, wild adult male desert tortoise (Gopherus agassizii) with clinical signs of respiratory disease and elevated plasma biochemical analytes indicative of renal disease (blood urea nitrogen [415 mg/dl], uric acid [11.8 mg/dl], sodium [>180 mmol/l] and chloride [139 mmol/l]). Moderate numbers of birefringent oxalate crystals, based on infrared and electron microscopy, were present within renal tubules; small numbers were seen in colloid within thyroid follicles. A retrospective analysis of 66 additional cases of wild desert tortoises was conducted to determine whether similar crystals were present in thyroid and kidney. The tortoises, from the Mojave and Sonoran deserts, were necropsied between 1992 and 2003 and included juveniles and adults. Tortoises were classified as healthy (those that died due to trauma and where no disease was identified after necropsy and evaluation by standard laboratory tests used for other tortoises) or not healthy (having one or more diseases or lesions). For all 67 necropsied tortoises, small numbers of crystals of similar appearance were present in thyroid glands from 44 of 54 cases (81%) and in kidneys from three of 65 cases (5%). Presence of oxalates did not differ significantly between healthy and unhealthy tortoises, between age classes, or between desert region, and their presence was considered an incidental finding. Small numbers of oxalate crystals seen within the kidney of two additional tortoises also were considered an incidental finding. Although the source of the calcium oxalate could not be determined, desert tortoises are herbivores, and a plant origin seems most likely. Studies are needed to evaluate the oxalate content of plants consumed by desert tortoises, and particularly those in the area where the tortoise in renal failure was found.