Colour pattern influences behaviour and affects survival of organisms through perception of light reflectance. Spectrophotometric methods used to study colour optimise precision and accuracy of reflectance across wavelengths, while multiband photographs are generally used to assess the complexity of colour patterns. Using standardised photographs of sand lizards (Lacerta agilis), we compare how colours characterised using point measurements (using the photographs, but simulating spectrophotometry) on the skin differ from colours estimated by clustering pixels in the photograph of the lizard's body. By taking photographs in the laboratory and in the field, the experimental design included two 2-way comparisons. We compare point vs. colour clustering characterisation and influence of illumination in the laboratory and in the field. We found that point measurements adequately represented the dominant colour of the lizard. Where colour patterning influenced measurement geometry, image analysis outperformed point measurement with respect to stability between technical replicates on the same animal. The greater colour variation derived from point measurements increased further under controlled laboratory illumination. Both methods revealed lateral colour asymmetry in sand lizards, i.e. that colours subtly differed between left and right flank. We conclude that studies assessing the impact of colour on animal ecology and behaviour should utilise hyperspectral imaging, followed by image analysis that encompasses the whole colour pattern.
Six new species of coccidia are described from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) endemic to Mauritius, Indian Ocean. Five new species (3 Eimeria and 2 Isospora species) are described from Phelsuma rosagularis Vinson et Vinson; all lack a micropyle and an oocyst residuum, and all have a sporocyst residuum. Oocysts of Eimeria swinnertonae sp. n. are ellipsoidal, 22.2 × 17.8 (20.8-24.8 × 16.8-18.4) μm; SI 1.25; polar granule absent. Sporocysts are ellipsoidal, 8.8 × 7.0 (8.0-9.6 × 6.4-8.0) μm; SI 1.3; Stieda body absent. Oocysts of Eimeria stebbinsi sp. n. are ellipsoidal, 17.4 × 11.7 (16.0-19.2 × 11.2-12.8) μm; SI 1.5; polar granules present. Sporocysts are elongate-ellipsoidal, 7.7 × 4.0 (7.2-8.0 × 3.2-5.6) μm; SI 1.9; Stieda body present. Oocysts of Eimeria raleighi sp. n. are spheroidal to sub-spheroidal, 17.0 × 15.5 (16.0-19.2 × 14.4-16.8) μm; SI 1.1; polar granule present. Sporocysts are sub-spheroidal, 7.8 × 6.6 (7.2-8.0 × 6.4-7.2) μm; SI 1.2; Stieda body absent. Oocysts of Isospora cottinghamae sp. n. are ellipsoidal, 19.8 × 15.5 (17.6-21.6 × 14.4-17.6) μm; SI 1.3; polar granules present. Sporocysts are ellipsoidal, 10.8 × 6.9 (9.6-12.8 × 6.4-8.0) μm; SI 1.6; Stieda body present. Oocysts of Isospora pearlae sp. n. are ellipsoidal, 16.0 × 11.5 (15.2-17.6 × 9.6-12.8) μm; SI 1.4; polar granule present. Sporocysts are ellipsoidal, 8.8 × 5.4 (8.0-9.6 × 4.8-6.4) μm; SI 1.6; Stieda and substieda bodies present. One new Eimeria species is described from the blue-tailed day gecko, Phelsuma cepediana Merrem. Oocysts of Eimeria hartleyi sp. n. are sub-spheroidal to ellipsoidal, 18.2 × 14.5 (16.0-20.8 × 13.6-16.0) μm; SI 1.26; polar granules present. Sporocysts are ellipsoidal to cylindroidal, 7.5 × 5.3 (6.4-8.0 × 4.8-6.4) μm; SI 1.4; Stieda body present. We report the presence of tetrazoic spheroidal to sub-spheroidal oocysts or sporocysts 10.2 × 8.5 (9.9-10.4 × 8.3-8.8) μm; SI 1.2 from an individual of P. cepediana. These oocysts or sporocysts are significantly larger than the Cryptosporidium species so far described from reptiles, and likely represent excretion of spuriously ingested sporocysts of a Sarcocystis or Adelina coccidian.