Mitogenomic phylogeny of Truncatelloidea with description of Aenigmula sinensis Tang, Han & Kong, sp. nov. (Mollusca, Gastropoda, Littorinimorpha, Truncatelloidea) Author Tang, Jiaze https://orcid.org/0009-0006-7148-8340 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China Author Gong, Jihang https://orcid.org/0009-0000-0083-5495 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China Author Han, Xiao https://orcid.org/0009-0002-6607-3002 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China Author Fan, Yan https://orcid.org/0009-0001-9709-7130 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China Author Zhang, Xinni https://orcid.org/0009-0007-6044-6804 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China Author Kong, Lingfeng 0000-0001-5263-1697 Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao 266003, China & Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao Marine Science and Technology Center, Qingdao, Shandong 266237, China text ZooKeys 2026 2026-05-19 1279 357 378 journal article 315223 10.3897/zookeys.1279.183841 59a08d42-dfc9-4676-9f4c-98e26b16abb6 9AB6EB9A-4A2F-43D2-95F3-4A7433102120

Table 4. Morphological comparison of the three species of Aenigmula.

Character and Habitat	A. criscionei	A. sinensis sp. nov.	A. sp.
Location	Northern Territory, Australia	Shangdong, China	Jiangsu, China
Habitat	Mangrove forest	Rocky reef in muddy intertidal zones	Rocky reef in muddy intertidal zones
Size (length, mm)	2.14–2.93	2.57–3.27	7.70
Shell
Shape	Ovate-conical	Elongated-conical	Fusiform
Color	Glossy, golden	Pale yellow and translucent	Yellowish-white and translucent; apex pale green (possibly environmentally induced)
whorls	5–6	5–6	6–7
Periphery	Straight-sided to slightly convex	Slightly convex to convex	Slightly convex
Suture	Smooth	Distinct	Smooth
Aperture	Teardrop-shaped	D-shaped	Teardrop-shaped
Protoconch	Dome-shaped	Dome-shaped	Dome-shaped
Sculpture	Smooth except for growth lines	Smooth except for growth lines	Smooth except for growth lines
Radula
Central tooth	3–4 + 1 + 3 - 4 / 1 + 1	3 + 1 + 3 / 1 + 1	3 + 1 + 3 / 1 + 1
Lateral tooth	4–5 + 1 + 5 – 6	5–6 + 1 + 5	8 + 1 + 3–5
Inner marginal	~ 20	~ 25	~ 20
Outer marginal	~ 20	10-15	Unknown
Operculum	Teardrop-shaped, paucispiral, nucleus eccentric	D-shaped, paucispiral, nucleus eccentric	Unknown