Lucasioides dissectus Li & Wang 2024, sp. nov.
Creators: name: Wang, Jin
name: Yao, Chong-Hui
name: Jiang, Chao
name: Li, Wei-Chun
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Agnaridae
Lucasioides
Lucasioides dissectus

description: 3.3. 1.Lucasioides dissectusLi & Wang sp. nov.
Figures 6 A, 7
Type material.
Holotype. CHINA • ♂; Jiangxi Province, Jiujiang City, Nanshan National Forest Park; 29.2514 ° N, 116.2071 ° E; el. 79 m a. s. l.; 17. viii. 2022; W. C. Li leg. (DNA nos. NS 2201, Prep. slide no. L 22090). — Paratypes. • 3 ♂♂, 2 ♀♀; same data as the holotype (DNA nos. NS 2002 - NS 2004); CHINA • 3 ♂♂, 5 ♀♀; Jiangxi Province, Pingxiang City, Nankeng Forest Farm; 27.4650 ° N, 113.8940 ° E, el. 590 m a. s. l.; 21. vi. 2011; W. C. Li leg. (DNA nos. NKLC 2001 - NKLC 2008, Prep. slide nos. L 17321 - L 17326).
Diagnosis.
Pereonite 1 with acute postero-lateral corner; pleopod 1 exopod with bilobed apex, and outer lobe approximate three times as long as inner lobe.
Description.
Body length of males 7.0- 8.5 mm, of females 7.5-9.5 mm. Color in alcohol brown, dorsum granulated, bearing irregular white muscle spots (Fig. 6 A). Pereonite 1 sinuous on posterior margin of epimeron, postero-lateral corner acute. Noduli laterales as in Fig. 7 A. Telson triangular, slightly wider than long, lateral margins concave, apex blunted round; uropod exopodite about twice as long as basipodite (Figs 6 A, 7 A). — Cephalon with triangular median lobe, median lobe shorter than lateral lobes (Figs 6 A, 7 A). Antennula with several aesthetascs on distal tip and antero-lateral margins of third article (Fig. 7 B). Antennal flagellum with first segment two thirds as long as second one (Fig. 7 C). — Pereopod 1 with brush of long setae on carpus and merus (Fig. 7 D). Pereopod 7 ischium with deep depression on rostral surface, carpus slightly expanded near middle on dorsal margin (Fig. 7 E). — Pleopods 1-5 exopods with Protracheoniscus - type pseudotrachea (Fig. 7 F-J). — MALE: pleopod 1 exopod conspicuously bilobed at posterior tip, outer lobe approximate three times as long as inner lobe, endopod with broad basal part, narrowed towards beak-shaped posterior tip (Fig. 7 F); pleopod 2 endopod styliform, nearly as long as exopod (Fig. 7 G).
Etymology.
Latin “ dissectus ” = partite. The new species name refers to the male pleopod 1 exopod conspicuously bilobed at apical apex.
Remarks.
The new species is very similar to L. isseli (Arcangeli, 1927) in having the apical tip of pleopod 1 exopod conspicuously bilobed, and the outer lobe much longer than the inner lobe. But it can be distinguished by the shape of median lobe of the cephalon angled in anterior middle margin, and pereonite 1 with an acute postero-lateral corner (Fig. 6 A). In L. isseli, the median lobe of the cephalon is arched in anterior middle margin, and pereonite 1 with a broad rounded postero-lateral corner (Fig. 6 B). This species also resembles L. dianensis sp. nov. in having the apical tip of pleopod 1 exopod conspicuously bilobed (Figs 6 A, 7 versus 6 C, 8). But it can be distinguished in having the outer lobe of pleopod 1 exopod three times as long as inner lobe (Fig. 7 F). In L. dissectus, the outer lobe is twice as long as inner lobe (Fig. 8 F). However, the above three species with minor differences in the external appearances or mounted appendages. We are not sure these ambiguous different traits belong to intraspecific variations or interspecific divergences. In the morpho-geometric analysis of geometric morphometrics, the scatter diagrams indicate that the CVAs were able to clearly classify the three species with the first two canonical variables (Figs 3, 4). Furthermore, they can also be separated based on molecular analyses (Fig. 5). Thus, we clarified the above dilemma by using the integrative approaches.
description: Published as part of Wang, Jin, Yao, Chong-Hui, Jiang, Chao & Li, Wei-Chun, 2024, Integrative taxonomy reveals exceptional species diversity of Lucasioides from China (Isopoda: Oniscidea: Agnaridae), pp. 527-549 in Arthropod Systematics & amp; Phylogeny 82 on pages 527-549, DOI: 10.3897/asp.82.e113041