Morphological identification and phylogenetic analysis of pentastomids in snakes from Guangxi

doi:10.12140/j.issn.1000-7423.2026.04.016

Abstract

Abstract:

Objective To investigate the prevalence of pentastomid infections in snakes from Guangxi and conduct phylogenetic analysis. Methods Snakes that died during rescue and management at the Nanning Municipal Wild Animals and Plants Protection Station between September 2011 and December 2022 were collected and necropsied, and pentastomid adults and nymphs were recovered. Parasite morphology was examined under an optical microscope, and body length, number of abdominal annulations, hook measurements, and male copulatory spicules were recorded, while tegumental ultrastructure was examined by scanning electron microscopy. In addition, the pentastomid 18S ribosomal RNA (18S rRNA) gene was amplified using PCR assay, followed by sequence alignment and phylogenetic analyses. Results A total of 158 snakes were collected, and the detection rate of pentastomids was 15.19% (24/158). A total of 162 pentastomid specimens were recovered, with a mean infection intensity of 6.75 worms per infected snake. Based on morphological characteristics, the specimens were provisionally characterized as Raillietiella, Kiricephalus, and Waddycephalus. Sequencing of pentastomid adults and nymphs revealed that the 18S rRNA gene sequences had valid sequence lengths of 1 776 to 1 796 bp, and were deposited in GenBank under accession numbers KC904945, KC904947, MH194559, and KC904946. These sequences showed 98.62% similarity to Hispania vulturis (GenBank accession No. AY304520), 99.22% similarity to Kiricephalus sp. (GenBank accession No. MZ919326), and 98.50% similarity to Levisunguis subaequalis (GenBank accession No. MN065568), respectively. Phylogenetic analysis revealed that R. orientalis was located within the Raillietiella-related lineage, whereas K. pattoni adults and nymphs and W. radiata were located within the Porocephalus-related lineage. K. pattoni adults and nymphs were clustered into a clade with 99% bootstrap support. The genetic distance between sequences of K. pattoni adults (GenBank accession number: KC904947) and nymphs (GenBank accession number: KC904946) was 0.002 4, with only four nucleotide differences, while the genetic distances between each of these sequences and the reference sequence of Kiricephalus sp. (GenBank accession number: MZ919326) were both 0.007 9. Conclusion Pentastomids were detected in snakes from Guangxi, and the recovered specimens were identified as R. orientalis, K. pattoni, W. radiata, and Waddycephalus sp.

Key words: Pentastomida, Morphological identification, Scanning electron microscopy, 18S rRNA, Phylogenetic analysis

CLC Number:

R383.9

ZHOU Qing’an, CHEN Zimei, ZHENG Min, BI Jingshan, LI Yiqin, HU Wei, LI Jian. Morphological identification and phylogenetic analysis of pentastomids in snakes from Guangxi[J]. CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES, 2026, 44(4): 565-571.

Figures/Tables 6

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宿主 Host	蛇数 No. examined	检出率/% Detection rate/%	感染度 Infection intensity range	寄生部位 Site of infection
眼镜蛇 N. atra	49	15（30.6）	1~33	肺部和体腔 Lungs and body cavity
滑鼠蛇 P. mucosa	105	7（6.7）	1~5	肺部、皮下 Lungs; subcutaneous tissue
草腹链蛇 A. stolatum	1	1（1/1）	51	肺部和体腔 Lungs and body cavity
三索锦蛇 C. radiatus	1	1（1/1）	2	肺部 Lungs
王锦蛇 E. carinata	2	0	0	-