Histological and histochemical characteristics of the oral, pharyngeal and accessory digestive organs in the water monitor lizard (Varanus salvator) from Thailand.

Srichairat, N., Taksintum, W., & Chumnanpuen, P. (2022). Histological and histochemical characteristics of the oral, pharyngeal and accessory digestive organs in the water monitor lizard (Varanus salvator) from Thailand. Anatomia Histologia Embryologia, 51, https://doi.org/10.1111/ahe.12846. The water monitor lizard (Varanus salvator) is largely distributed in Southeast Asia, especially Thailand, which the microanatomical structure studies on this particular species have been limited. Therefore, the purpose of this study is to examine and describe the oral, pharyngeal and accessory digestive organs' histological and histochemical characteristics. Histological and histochemical examinations were performed on the two specimens (male and female). The majority of V. salvator oral, pharyngeal and accessory digestive organs are similar to those of other vertebrates, according to the results of the histological investigation. However, several unique characteristics have been observed, such as the dentine lamella (plicidentine fold) at the tooth root structure was discovered to be attached to the jaw bone, the absence of lingual papillae and taste buds on the tongue, and the absence of inner surface folding structures in the gallbladder. Regarding mucin histochemical investigation, acid and neutral mucins were discovered in the pharyngeal glands of V. salvator, whereas only acid mucin was found in the mandibular salivary glands. This study reveals the histological and histochemical characteristics of V. salvator oral, pharyngeal and accessory digestive organs, which could be employed to improve digestive tract function, as well as the necessity of understanding animal digestive processes.

Two new species of Hemiphyllodactylus Bleeker (Squamata: Gekkonidae) from Thailand.

We investigate the taxonomy of slender geckos (Hemiphyllodactylus) in Thailand by means of molecular phylogenetics and morphological study using specimens from three provinces; Chiang Mai, Kamphaeng Phet, and Chanthaburi. The results of phylogenetic analyses had shown that the genetic data of populations from 2 provinces were distinctly different from known species. In addition, some morphological characters of these two populations such as lamellar formula on fore- and hindfoot differed from the other species. The integrated taxonomy using molecular phylogenetics and morphological study revealed two new species, Hemiphyllodactylus khlonglanensis sp. nov. from western Thailand, and Hemiphyllodactylus flaviventris sp. nov. from eastern Thailand as described herein.

A new caruncle-bearing Limnonectes (Anura: Dicroglossidae) from northeastern Thailand.

A new species of the dicroglossid frog genus Limnonectes is described from Ubon Ratchathani Province, northeastern Thailand. Limnonectes lauhachindai sp. nov. differs from its congeners by having males with a low-profiled, U-shaped caruncle with free posterior margin that completely occupies, but does not extend beyond, the interobital region. The new species is most closely related to L. gyldenstolpei and L. dabanus. Its description brings the total number of caruncle-bearing species of Limnonectes to five.

Annual changes in fecal sex hormones with corresponding changes in reproductive behaviors in Thai sarus crane, black-headed Ibis, and Lesser Adjutant Stork.

We monitored annual fecal sex hormones and reproductive displays of five individuals of males and females Thai sarus crane (Grus antigone sharpii), a flock of five males and females black-headed Ibis (Threskiornis melanocephalus), and five pair bonded lesser adjutant stork (Leptoptilos javanicus), all maintained in captivity at Bangprha Waterbird Breeding Research Center. Reproductive behaviors were observed during 0600-1800 h, for four days during the second week of each month and feces were collected monthly to determine annual male total testosterone (mTT) and female estradiol (fE2) levels by radioimmunoassay. Thai sarus crane exhibited a peak mTT in August following a fE2, with a surge in July. Black-headed ibis demonstrated a peak mTT in January prior to a fE2 with a surge in March. Lesser adjutant stork showed a maximal mTT coincidently with fE2 with a surge in October. Thai sarus crane frequently displayed courtship in May-October, corresponding well with higher mTT rather than fE2 levels. Black-headed ibis showed courtship-copulation displays in January, simultaneously with mTT, but not with fE2 surge. Lesser adjutant stork often displayed courtship-copulation in October-January, seemingly corresponded with higher mTT and fE2 levels during October-December and October-November, respectively. Male and female lesser adjutant stork displayed egg-incubation and chick-rearing behaviors in November-January and December-June, respectively. We suggest that mTT and/or fE2 apparently played an important role in regulation of courtship-copulation displays but did not relate to both egg-incubation and chickrearing behaviors.

Re-evaluating the taxonomic status of Chiromantis in Thailand using multiple lines of evidence (Amphibia: Anura: Rhacophoridae).

Because of general phenotypic similarities and distribution of species across two continents, the genus Chiromantis has proven somewhat enigmatic. Among Indochinese species, the validity of C. hansenae has been questioned by some who consider it a junior synonym of C. vittatus. We employ three lines of evidence to elucidate the taxonomic status and phylogenetic relationships of four congeneric species of Chiromantis frogs from Thailand. Results of molecular, morphological, and bioacoustic data analyses support at least four evolutionarily distinct and monophyletic clades: C. doriae, C. nongkhorensis, C. vittatus and C. hansenae. Genetic divergence between C. vittatus and C. hansenae is > 10%, significantly greater than C. doriae and C nongkhorensis (4.5%). Our results support the taxonomic validity of C. hansenae and suggest that there may be more diversity within C. hansenae and C. vittatus than is currently recognized.