Vietnamella maculosa, Auychinda & Sartori & Boonsoong, 2020
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publication ID |
https://dx.doi.org/10.3897/zookeys.902.46844 |
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publication LSID |
lsid:zoobank.org:pub:5086252D-43AC-4214-9D74-0987C59AB555 |
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persistent identifier |
https://treatment.plazi.org/id/E75B83EC-A077-4533-83EC-224D5A26E1DA |
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taxon LSID |
lsid:zoobank.org:act:E75B83EC-A077-4533-83EC-224D5A26E1DA |
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treatment provided by |
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scientific name |
Vietnamella maculosa |
| status |
sp. nov. |
Vietnamella maculosa sp. nov. Figs 1A View Figure 1 , 2A-G View Figure 2 , 3A-L View Figure 3 , 4A, D, G, J View Figure 4 , 5A, B View Figure 5 , 6A-C View Figure 6
Material examined.
Holotype: 1 male larva Thailand, Chiang Rai Province, Mueang Chiang Rai, Pong Phra Bat waterfall, 20°00'41.0"N, 99°48'15.0"E, 470 m, 6.V.2019, D. Chainthong leg. [ZMKU]. Paratypes: 2 larvae same data as holotype; 1 larva on slide [ZMKU] and another in ethanol [MZL GBIFCH00673059]. Both paratypes were used for DNA extraction.
Description.
Mature larva (in alcohol, Fig. 1A View Figure 1 ). Body length 11.25 mm without cerci; cerci 4.8 mm; body brown with dark brown markings on thorax and femora.
Head. Brown with a pair of occipital tubercles, a single sub-occipital tubercle medially; two projections below eyes; inner pairs of projections small, spine-like and sharp (Fig. 2A View Figure 2 ); outer pair large, triangular, cone shaped without any serrated spines (Fig. 4A, D View Figure 4 ). Labrum, similar to other vietnamellid mayflies, anterior half of dorsal surface and margins with relatively long setae, ventral surface with short setae (Fig. 2B View Figure 2 ). Labium, glossae width greater than length, glossae and paraglossae with dense setae on surface, setae on dorsal surface and margins longer; labial palpi three segmented, basal segment broader and longer than the second, apical segment very small; palpi with tiny setae (Fig. 2C View Figure 2 ). Left mandible, slender, a little concave at sub-median area; molar block-like shape with a tuff of short setae below inner molar margin (Fig. 2D View Figure 2 ). Right mandible, slender, slightly concave at sub-median area; molar block-like shape with a row of setae below inner molar margin (Fig. 2E View Figure 2 ). Maxillae slender; maxillary palpi three segmented, with tiny setae; length ratio from basal to apical = 1.3:1.2:1 (Fig. 2F View Figure 2 ). Hypopharynx, lingua square and superlinguae nearly round, with setae on surface (Fig. 2G View Figure 2 )
Thorax. Pronotum with small moderately sharp anterolateral projections, and slightly pointed protuberances below the anterolateral projection (Fig. 3A View Figure 3 ). Forefemur, strongly expanded with serrations or teeth projections on ventral margin (Fig. 3B View Figure 3 ); transverse ridge serrated with small rounded setae (Fig. 5A, B View Figure 5 ) and long thin setae near inner dorsal margin. Midfemur without any projection, expanded, dorsal margin convex apically and with a row of hair-like setae (Fig. 3C View Figure 3 ). Hindfemur without any projection, expanded, longer than midfemur, dorsal margin with a row of hair-like setae (Fig. 3D View Figure 3 ). All claws similar, strongly hooked with a single small denticle basally (Fig. 3E View Figure 3 ).
Abdomen. Tergites I-X with a pair of median ridges or tubercles; posterolateral angles of tergites II-X extended into sharp projection; tergite VII with a pair of tubercles (Fig. 4G View Figure 4 ) and tergite X with well-developed a pair of tubercles (Fig. 4J View Figure 4 ); lateral margins of tergite with dense setae. Gill on segments I-VII: gill I finger-like with setae (Fig. 3F View Figure 3 ); gills on segments II-VI similar in structure, with dorsal and ventral lamellae, the latter further divided into two clusters, each with several smaller lobes (Fig. 3G-K View Figure 3 ); gill on segment VII small, with two lamellae but ventral lamella divided into three lobes (Fig. 3L View Figure 3 ). Caudal filaments with dense lateral setae on inner and outer margins of middle part.
Eggs. (dissected from mature larva). Length 200 µm, width 144 µm; oval shape, chorionic surface with small protuberances, half of egg covered with helmet-shaped polar cap (Fig. 6A View Figure 6 ); rod shaped KCT (Knob Terminated Coiled Thread) around egg body (Fig. 6B View Figure 6 ); 2 or 3 tagenoform-type micropyles at centre (Fig. 6C View Figure 6 ).
Diagnosis.
The larva of Vietnamella maculosa sp. nov. is most similar to that of V. thani and V. sinensis in the lack of serrations on the outer projection on the head, but it can be separated from V. thani based on the following characteristics: i) the pattern of serration on the ventral margin of the forefemur, ii) the setae on the transverse ridge of the forefemur, iii) a well-developed pair of median ridge projections of tergite X. It can be separated from V. sinensis by the proportion of the maxillary palp on the second segment, which is slightly longer than on the third segment (1.2:1), whereas in V. sinensis it is clearly longer (1.6:1).
Remarks.
The larvae of Vietnamella maculosa sp. nov. have a unique colour pattern, with brown and dark brown banding spread over the body and femurs. However, this colour can change in intensity depending on the life stage and environment. Other species, like V. thani , have variation in body colour but do not have this pattern.
Etymology.
The name maculosa (Latin for having spot or macula), refers to the brown and dark brown banding of the species.
Distribution.
Chiang Rai Province
Adult.
Unknown
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.