Dardanus cf. longior

Asakura, Akira, 2006, Dardanus sanguinocarpus Degener, 1925 (Crustacea: Decapoda: Anomura: Diogenidae) species complex: a redescription of D. sanguinocarpus and descriptions of three new species, Zootaxa 1230, pp. 1-54 : 48-51

publication ID	https://doi.org/ 10.5281/zenodo.172729
DOI	https://doi.org/10.5281/zenodo.6259133
persistent identifier	https://treatment.plazi.org/id/039D87E1-C43C-1F74-4B5C-FEB9DB9DF925
treatment provided by	Plazi
scientific name	Dardanus cf. longior
status

Treatment

Dardanus cf. longior View in CoL

( Figs. 15 View FIGURE 15 B, 30–32)

Dardanus sanguinocarpus View in CoL . — Poupin, 1998: 38; 2004 (not Dardanus sanguinocarpus Degener, 1925 View in CoL )

Material examined

1 ♂, SL 12.2 mm, Anao Bay, Huku Hiva, Marquesas, French Polynesia, coll. P. Laboute by snorkeling, 21 Sept. 1997, MNHN Pg 5907.

Diagnosis

Shield and cephalic appendages similar to those of D. longior except for larger number of spines (9–11 spines) on dorsomesial margin of antennal acicle.

Left cheliped ( Fig. 30 View FIGURE 30 AC) with palm and fixed finger outer face bearing prominent, truncate corneoustipped spines each accompanied with single short seta ( Fig. 30 View FIGURE 30 C) (number of spines comparatively fewer and spines much larger than those of D. longior ), longitudinal row of corneous spines present on midline of outer face, lower half of outer face concave; lower margin with row of prominent truncate corneoustipped spines (this structure lacking in D. longior ) and stiff setae; lower portion of inner face with numerous short corneous spines and many tufts of stiff setae (spines much larger than those in D. longior ); upper face of palm with 1 or 2 irregular rows of prominent sharp corneoustipped spines. Carpus, merus and ischium similar to those of D. longior .

Right cheliped with numerous tufts of setae on outer, upper and lower faces; armature similar to that of D. longior . Second and right third pereopods similar to those of D. longior .

Left third pereopod ( Figs. 30 View FIGURE 30 D–F, 31) with dactyl similar to that of D. longior except for dorsal row of generally unarmed lobes ( Fig. 30 View FIGURE 30 E) (vs. distally armed with spines in D. longior ) and unarmed dorsomesial face ( Fig. 30 View FIGURE 30 F) (vs. armed with numerous strong spines in D. longior ). Propodus with lateral face bearing dorsal row of lobes (Fig. 31Aa) each armed distally with generally 1 (ranging 1–4) flattened, elongate rectangularcorneous spines, dorsal half with very deep longitudinal concavity (Fig. 31Ab), separated by narrow medial longitudinal elevation (Fig. 31Ac) armed with 1 irregular row of protuberances each with marginal 1–8 flattened, elongate rectangular corneous spines, ventral 0.3–0.4 (Fig. 31Ad) with 1–3 irregular rows of protuberances each armed with marginal flattened, elongate rectangular corneous spines; ventromesial margin (Fig. 31C) with series of deep furrows producing row of large lobes each bearing 1–4 very large, conical corneous spines and stiff setae. Carpus and merus similar to those of D. longior .

Sternite of third pereopods with single protrusion, fourth and fifth pereopods and uropod similar to those of D. longior .

Male pleon with small, hookshaped fleshy membranous protuberance present between fourth and fifth pleopods. Female pleon unknown.

Dardanus cf. longior : ɗ, SL 12.2 mm, Marquesas, French Polynesia, MNHN Pg 5907. Propodus of left third pereopod: A, lateral, a, dorsal row of lobes; b, dorsal deep longitudinal concavity; c, medial longitudinal elevation; d, ventral concavity; B, dorsomesial; C, ventromesial margin.

Telson generally similar to that of D. longior , with posterior lobes bearing 7 (right) or 9 (left) spines on terminal margin.

Color in life ( Fig. 15 View FIGURE 15 B)

Dorsal surface of shield pinkish gray, with bright red area, midanteriorly. Ocular peduncles pinkish gray, gradually changed to yellow distally. Chelipeds and ambulatory pereopods generally pinkish gray, tips of fingers of chelipeds and dactyls of ambulatory pereopods whitish; carpi and meri of chelipeds and carpi of ambulatory pereopods each with bright red area; articulation of carpi and meri of ambulatory pereopods whitish. Posterior carapace and pleon generally pinkish gray, with mottled white and red.

Remarks

Several minor differences are noted between this specimen and Dardanus longior , sp. nov., as mentioned above. This specimen is comparatively larger than the specimens of D. longior so that the difference may be attributable to allometry. Since only one specimen is presently known, however, I tentatively refer this specimen to Dardanus cf. longior until more material becomes available.