RESUMO
Based on morphological and molecular analyses, we herein describe a new species of Achalinus from northern Vietnam. Achalinus quangi sp. nov. differs from its sister taxon, A. emilyae, and other members of the genus Achalinus by at least 4% in terms of genetic divergence based on fragments of the mitochondrial COI and Cytb genes and a combination of the following morphological characters: (1) maxillary teeth 27-29; (2) suture between the internasals distinctly longer than that between the prefrontals; (3) loreal not fused with prefrontal, extending from the nasal to the eye; (4) supralabials six; (5) infralabials five; (6) postocular absent, temporals 2+2, only the upper one in broad contact with eye; (7) dorsal scales in 25(23)-23-23(21) rows, keeled; (8) ventrals 139-141 in males, 141-154 in females; (9) subcaudals 75-84 in males, 69 in the female, all unpaired; (10) cloacal entire; (11) dorsum reddish brown to brown. Achalinus quangi sp. nov. consists of two subclades, the first one occurring on the northern side of the Da River in Son La and Tuyen Quang provinces and another subclade found on the southern side in Thanh Hoa, Nghe An, and Ha Tinh provinces. These two subclades are separated from each other by 1.8 to 2.3% genetic divergence and are slightly differing in ventral scalation.
RESUMO
A new, critically endangered species of softshell turtle, Pelodiscusvariegatus sp. n. is described from north-central Vietnam and Hainan Island, China, distinguished by a unique set of genetic and morphological traits from all other congeners (P.axenaria, P.maackii, P.parviformis, P.sinensis, and unnamed genetic lineages). Morphologically, P.variegatus is characterized, among others, by its strong ventral ornamentation in all age classes.
RESUMO
Strongyluris calotis is a heterakid nematode in the large intestine of agamid lizards (Reptilia: Sauria: Agamidae) from the Oriental Region. The standard light microscopic definition of the species counts the "caudal papillae" as 10 pairs on male worms. However, previous work from our group using scanning electron microscopy (SEM) on the heterakid from agamid lizards in Japan, Taiwan, and Singapore revealed that this counting contained a pair of phasmids and that two pairs of postcloacal papillae were completely fused to form a pair of united papillae, thus resulting in "10 pairs." In the present study, we examined S. calotis specimens from the Emma Gray's forest lizard, Calotes emma (Agamidae), living in the plain forest at low altitude, and the Vietnam false bloodsucker, Pseudocalotes brevipes (Agamidae), living in the mountainous forest at high altitude in the northern part of Vietnam. Using SEM, the arrangement of caudal papillae in male worms from an Emma Gray's forest lizard was found to be comparable to classical S. calotis specimens from agamid lizards collected in Japan, Taiwan, and Singapore. However, male worms from Vietnam false bloodsuckers did not have a pair of united papillae but had 10 pairs of independent caudal papillae with a pair of phasmids. Molecular genetic analyses of the ribosomal RNA gene (rDNA) of worms of the classical S. calotis morphotype from Japan and Singapore and two S. calotis morphotypes from Vietnam demonstrated absolutely identical nucleotide sequences of partial 18S rDNA (at least 1764 base pairs (bp)) and 5.8S rDNA (158 bp). However, intraspecific differences were detected in other regions of the rDNA, related to the geographical distribution of hosts regardless of morphotype: 97.8-98.5 % identity (443-446 bp/453 bp) in the internal transcribed spacer (ITS)-1 region, 96.6-98.0 % identity (425-431 bp/440 bp) in the ITS-2 region, and 99.6-99.7 % identity (1149-1151 bp/1154 bp) in the 28S rDNA. Thus, in the future, taxonomic relationships of S. calotis distributed widely in the Oriental Region as well as other nominal Oriental Strongyluris spp., currently six in number, need to be extensively explored based on molecular genetic analyses in addition to intensive morphological characterization.