Vichai, Cumberlidge & Daniels & Soma & Leever, 2023

Cumberlidge, Neil, Daniels, Savel R., Soma, Julia B. & Leever, Ellen M., 2023, Vichai cyanapelou gen. et sp. nov. (Crustacea: Deckeniidae: Hydrothelphusinae), a new genus and new species of freshwater crab from northern Madagascar, Journal of Natural History 57 (5 - 8), pp. 463-474 : 465-470

publication ID

https://doi.org/ 10.1080/00222933.2023.2192431

DOI

https://doi.org/10.5281/zenodo.7859819

persistent identifier

https://treatment.plazi.org/id/503B8E36-676C-B147-FDA0-A7AFE9555CB5

treatment provided by

Plazi

scientific name

Vichai
status

gen. nov.

Vichai gen. nov.

( Figures 1 View Figure 1 (a,b), 2(a–i), 3(a–d); Table 1 View Table 1 )

Nomenclatural statement

A life science identifier (LSID) number was obtained for the new genus: urn:lsid:zoobank.org:pub:46218584-43FE-4C05-9537-FFC81EACCFDB

Synonymy

′New genus E̍, Cumberlidge et al. (2020): fig. 1.

Type species

Vichai cyanalepou sp. nov., by present designation, gender masculine.

Diagnosis

Carapace moderate height (CH/FW 1.0); front broad (CW/FW = 3.1), deflexed; surface with faint carinae in anterolateral and posterlateral regions, otherwise smooth; anterolateral margin between exorbital tooth, epibranchial tooth concave, granulated,lacking intermediate tooth; epibranchial tooth reduced to small granule, close to exorbital tooth, positioned in line with postorbital margin; lateral margin strongly convex, lined with granules, posterior end curving inward, not continuous with posterolateral margin; postfrontal crest faint, incomplete, not traversing entire carapace, epigastric crests faint, in advanced position, in line with postorbital margin, postorbital crests faint, ending before meeting epibranchial teeth; semicircular, cervical sulci deep, cervical sulcus ending before meeting postorbital crest ( Figure 1 View Figure 1 (a)). Suborbital, subhepatic regions of branchiostegite with faint granules, pterygostomial region smooth except for granules along epimeral (longitudinal) sulcus; vertical sulcus on branchiostegite curved, granular, running downward from base of epibranchial tooth to epimeral sulcus ( Figure 1 View Figure 1 (b), 2(a)). Epistomial tooth triangular, deflexed, edges with faint granules, epistomial margins smooth ( Figure 2 View Figure 2 (a)); anterior lobe on terminal article of mandibular palp small (MPAL/MPTA = 0.4) ( Figure 2 View Figure 2 (i)). Ambulatory legs (P2–5) stout, not elongated (P2–5/CW = 5.4) ( Figure 1 View Figure 1 (a); Table 1 View Table 1 ); cheliped ischium margins smooth, rounded ( Figure 2 View Figure 2 (d)); third maxilliped exopod with long flagellum (~0.5× merus length) ( Figure 2 View Figure 2 (g,h)). G1TA medium length (G1TA/G1SA = 0.3), slim, basal two-thirds directed outward, distal third curving upward, tapering to blunt open tip; G1TA ventral side with faint sulcus between G1TA-G1SA junction ( Figure 3 View Figure 3 (a)); G1TA dorsal side with broad, trapezoid dorsal membrane (DM) at G1TA-G1SA junction; DM superior margin arrowhead-shaped, inferior margin U-shaped, lateral margin short, mesial margin elongated ( Figure 3 View Figure 3 (b)); G1SA lacking raised rounded shoulder on external margin near G1TA-G1SA junction ( Figure 3 View Figure 3 (a,b)); G2TA distinctly elongated, flagellum-like (G2TA/G2SA = 0.85) with pointed tip ( Figure 3 View Figure 3 (d)).

Distribution

Endemic to Madagascar. Vichai gen. nov. is currently known only from Marojejy National Park in the Sava Region in northern Madagascar.

Etymology

The genus is named in honour of Vichai Srivaddhanaprabha , the owner of the English Premier League football club Leicester City (LCFC) from 2010 until his death in a tragic helicopter crash at the King Power Stadium in October 2018. Vichai was not only extremely mindful of the Leicester community and the LCFC supporters, but under his leadership the Football Club won the 2015–16 English Premier League title against all expectations, after starting the season as 5000/1 rank outsiders. The generic name, Vichai , is used as a Latin noun in nominative singular and treated as masculine.

Remarks

The genus Vichai is established for a new species, V. cyanalepou (see later). The recognition of the present new genus is based on phylogenetic and morphological evidence. The molecular phylogeny in Cumberlidge et al. (2020, fig. 1, ′New genus E̍) indicates that V. cyanalepou sp. nov. is part of a unique basal clade that is clearly genetically separate from all other Malagasy genera. Mophologically, Vichai gen. nov. can be distinguished from the three other genera found in the Marojejy National Park (i.e. Foza Reed and Cumberlidge, 2006 , Hydrothelphusa A. Milne-Edwards, 1872 , and Marojejy Cumberlidge, Boyko and Harvey, 2002 ) as follows. The G1TA of Vichai gen. nov. is medium in length (G1TA/ G1SA = 0.3) and slim where the basal two-thirds are directed outward and the distal third curves upward ( Figure 3 View Figure 3 (a–c)) vs a G1TA that is short (G1 TA/ SA = 0.25), straight, and broadly conical in Foza (see Leever et al. 2022, fig. 7 g,h). The exorbital and epibranchial teeth in Vichai gen. nov. are separated by a shallow notch ( Figure 1 View Figure 1 (a)), whereas these teeth are separated by a deep cleft in Hydrothelphusa A. Milne-Edwards, 1872 (see Cumberlidge and Sternberg 2002, fig. 1a–c; Cumberlidge et al. 2007, figs 1, 16). Finally, the ambulatory legs of Vichai gen. nov. are short and stout (ΣP2–5/CW = 5.4) ( Figure 1 View Figure 1 (a); Table 1 View Table 1 ) and its eyestalks and corneas are of normal length ( Figures 1 View Figure 1 (a), 2(a)), whereas the ambulatory legs of Marojejy Cumberlidge et al. (2002) are elongated and slender (ΣP2–5/ CW = 7.0) and its eyestalks are short, taper distally, and have a reduced cornea (see Cumberlidge et al. 2002, fig. 2f).

The medium-sized anterior lobe on the terminal article of the mandibular palp of Vichai gen. nov. (MPAL/MPTA = 0.4) ( Figure 2 View Figure 2 (i)) distinguishes it from three other Malagasy genera: Boreathelphusa ( Cumberlidge, 2010) , Madagapotamon Bott, 1955 and Skelosophusa Ng and Takeda (1994) . In all three of these genera, the anterior lobe on the mandibular palp is noticeably small (MPAL/MPTA = 0.2), and ledge-like (see Cumberlidge and Sternberg 2002, fig. 4 h–l) rather than a broad rounded lobe as in Vichai gen. nov. ( Figure 2 View Figure 2 (i)).

Vichai gen. nov. can be distinguished from the remaining Malagasy genera as follows. The postfrontal crest of Vichai gen. nov. is incomplete and faint and does not traverse the entire carapace ( Figure 1 View Figure 1 (a)), whereas the postfrontal crest is well defined and completely traverses the carapace in Agora (see Cumberlidge et al. 2020). The anterolateral regions of the carapace surface of Vichai gen. nov. are mostly smooth and only faintly carinated ( Figure 1 View Figure 1 (a)), vs anterolateral regions of the carapace that have fields of well-defined carinae in Crosnautes (see Cumberlidge et al. 2021, fig. 1a,b). The G1TA of Vichai gen. nov. is slim, tapers evenly, and curves upward distally ( Figure 3 View Figure 3 (a,b)), vs a G1TA that is broadest at the midpoint and is straight along its length in Glabrithelphusa Meyer et al. (2014) (see Meyer et al. 2014, figs 1a, 3a). The lateral carapace margin of Vichai gen. nov. is lined with small granules (Figure (1a)), vs a lateral margin that is lined with either small or medium-sized teeth in Malagasya Cumberlidge and Sternberg (2002) (see Cumberlidge and Sternberg 2002, fig. 1e,f; Cumberlidge et al. 2020, fig. 10a,c,e).

Vichai gen. nov. can be also distinguished from Toamasina Leever et al. (2022), as follows. The margins of the cheliped ischium of Vichai gen. nov. are smooth and rounded ( Figure 2 View Figure 2 (d,e)), vs cheliped ischium margins that are lined with small teeth (see Leever et al. 2022, fig. 4 g,h); the exopod of the third maxilliped of Vichai gen. nov. has a mediumlength flagellum (~0.5× merus length) ( Figure 2 View Figure 2 (g,h)), vs a third maxilliped exopod with an elongated flagellum (equal to the merus length) (see Leever et al. 2022, fig. 2 f). In addition, the ambulatory legs of Vichai gen. nov. (P2–5) are short and stout (ΣP2–5/ CW = 5.4) ( Figure 1 View Figure 1 (a); Table 1 View Table 1 ), vs ambulatory legs (P2–5) that are medium length (ΣP2–5/CW = 6.4) in Toamasina (see Leever et al. 2022, table 3).

Finally, Vichai gen. nov. can be distinguished from Vahatra Leever et al. (2022) by the characters of the chelipeds. The inner margin of the cheliped carpus of Vichai gen. nov. has a relatively small pointed distal tooth, a smaller acute proximal tooth, and granules between these teeth ( Figure 2 View Figure 2 (f)), vs a cheliped carpus inner margin with a relatively larger, pointed distal tooth and a significantly smaller, acute proximal tooth, with no granules between the teeth in Vahatra (see Leever et al. 2022, fig. 4f). The cutting edge of the fixed finger (pollex of propodus) of the major (left) chela of Vichai gen. nov. has one large molar tooth flanked by small teeth proximally ( Figure 2 View Figure 2 (e)), whereas the fixed finger of the major (right) chela of Vahatra has four large molars proximally (see Leever et al. 2022, fig. 4 g,h). Further, the cutting edge of the movable finger (dactylus) of the major (left) chela of Vichai gen. nov. is lined with small teeth only and lacks large teeth ( Figure 2 View Figure 2 (e)), whereas the cutting edge of the movable finger of the major (right) chela of Vahatra has two large teeth proximally and one large tooth midway (see Leever et al. 2022, fig. 4 g,h).

GBIF Dataset (for parent article) Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF