Macrobrachium valdonii nom. nov., 2021

Mantelatto, Fernando L., Pileggi, Leonardo G., Pantaleao, Joao A. F., Magalhaes, Celio, Villalobos, Jose Luis & Alvarez, Fernando, 2021, Multigene phylogeny and taxonomic revision of American shrimps of the genus Cryphiops Dana, 1852 (Decapoda, Palaemonidae) implies a proposal for reversal of precedence with Macrobrachium Spence Bate, 1868, ZooKeys 1047, pp. 155-198 : 155

Macrobrachium valdonii nom. nov. comb. nov.

Cryphiops sbordoni Baldari, Mejía-Ortíz & López-Mejía, 2010: 48, figs 2-4. - Mantelatto et al. 2020: 915 (key).

Cryphiops (Bithynops) sbordonii . - De Grave and Fransen 2011: 316 (catalog). - Palacios-Vargas and Reddell 2013: 43 (in list). - Palacios-Vargas et al. 2014-2015: 22. - Quiroz-Martínez et al. 2014: table S1 (list). - Alvarez and Villalobos 2016: 250, table 8.1 (list).

Material examined.

Holotype: Mexico - Chiapas • male, cl 25 mm; Las Margaritas, Cueva Chamburro ; 01 Mar. 2001; V. Sbordoni leg.; CNCR 25106 . Paratypes: 1 ovigerous female, cl 22.5 mm, allotype; same data as for holotype; CNCR 25107 • 1 female, cl 12.3 mm; same data as for holotype; CNCR 25108 .

Description.

Rostrum. Short, straight, tip not reaching distal border of scaphocerite, almost reaching third article of antennular peduncle; upper margin bearing eight teeth, lower margin smooth.

Cephalon. Eyes reduced, globular cornea with facets, pigmented area reduced to a black point. Scaphocerite 2.4 × as long as wide.

Carapace. Smooth, maximum length 25 mm, with only antennal spine; branchiostegal groove shallow; hepatic spine absent.

Pereiopods . P1: slender, smooth, with few tufts of setae on both fingers; palm surpassing distal margin of scaphocerite; palm slightly compressed, as long as dactylus; carpus 1.75 × as long as palm, 1.12 × as long as merus. P2: subequal in size, subequal in size, reaching with half of carpus beyond scaphocerite, without spines; ischium 0.9 × merus; carpus 0.8 × as long as merus, 0.85 × as long as palm; propodus 1.5 × as long as dactylus, 2.5 × as long as carpus; palm semi-cylindrical, 3.3 × as long as high, with dispersed tufts of setae, 0.8 × as long as dactylus; fingers elongated, not gaping, cutting edges covered with tufts of setae, dactylus without teeth. P3: propodus, dactylus with several short setae, row of seven spines on ventral margin, propodus 3 × as long as dactylus, 2.05 × as long as carpus. P4: sparsely pilose, propodus 3.4 × as long as dactylus, 1.8 × as long as carpus, propodus with row of nine movable spines on ventral margin, propodus-dactylus articulation with pair of setae. P5: longest, propodus, carpus pilose, with longitudinal row of 12 movable spines, distal four close together, propodus-dactylus articulation with one spine; propodus 4 × as long as dactylus, 2.1 × as long as carpus.

Pleon. Smooth; somites 1-3 with pleura broadly rounded; somites 4 and 5 with posteroventral margin of pleura rounded; pleura of all somites bearing setae on ventral border; somite 6 nearly 1.5 × as long as somite 5. Inter-uropodal sclerite without keel-shaped pre-anal carinae.

Telson. Nearly 1.5 × longer than abdominal somite 6, shorter than uropodal rami, bearing two pairs of dorsal spines, first pair on distal fifth, second pair on middle section, with a single spine in the middle on left side; posterior margin broadly triangular bearing two pairs of lateral spines, inner pair 5 × longer than outer one, with plumose setae between inner spines, center ending in acute tip.

Etymology.

Baldari et al. (2010) named this species in honor of Prof. Valerio Sbordoni, a studious of the cave fauna of Chiapas, Mexico, and collector of the specimens. We maintained this homage by forming the specific epithet with parts of his first and last name.

Size.

See in material examined.

Color.

Live specimens are white, without pigment in/on the body.

Type locality.

Mexico Chiapas, Las Margaritas, Cueva Chamburro.

Distribution.

Only known from the type locality ( Baldari et al. 2010).

Life cycle.

Stygobitic species exclusive of inland waters, therefore independent of brackish waters to complete its life cycle. Female allotype with eggs (not measured).

Remarks.

Mejía-Ortíz et al. (2008) described Macrobrachium sbordonii from Mexico, naming it after Valerio Sbordoni. Shortly thereafter, Baldari et al. (2010) pay homage to the very same person again by describing a new species of Cryphiops also from Mexico. Since the synonymization of both genera makes the names secondary homonyms, Macrobrachium valdonii nom. nov., comb. nov. is proposed as a replacement name for Cryphiops sbordonii Baldari, Mejía-Ortiz & López-Mejía, 2010.

Similar to M. luscus comb. nov. (see remarks of that species and Table 2 ).