Callianidea mariamartae, Hernáez, Patricio & Vargas, Rita, 2013

Hernáez, Patricio & Vargas, Rita, 2013, A new species of Callianidea H. Milne Edwards, 1837 (Decapoda, Axiidea, Callianideidae) from the Pacific coast of Central America, with key to the genus, Zootaxa 3681 (2), pp. 147-154 : 148-152

Callianidea mariamartae , new species

Figs 1 A–I, 2A–H.

Type material. Holotype, male (CL: 12.4mm, TL: 50.1mm, Islotes Mogos, Osa, Golfo Dulce (08°38–03”N - 83°09–51”W), southern Pacific coast of Costa Rica, May 13 2012, collected by R. Vargas from intertidal zone, (specimen in excellent condition, not dissected, with both first pereiopods attached) ( MZUCR 2928-01). Paratype: female (CL: 11.1mm, TL: 42.6mm). Isla San José, Islas Murciélagos (10°50–59”N - 85°55–00”W), 10 Nov 2011, collected by R. Vargas from intertidal zone ( MZUCR 2921-09).

Other type material. Seventeen specimens were deposited in the Museo de Zoología, Escuela de Biología, Universidad de Costa Rica ( MZUCR: 2920-03, 2928-02, 2929-01, 2930-01, 2931-01, 2932-01). All specimens of Callianidea mariamartae n. sp. examined were caught in the sand under rocks from intertidal zone along the Pacific coast of Costa Rica.

Etymology. Patronym: gender female, named in honour of María Marta Chavarría, government official of the Santa Rosa National Park in recognition of her many important contributions to conservation and bio-awareness of the unique and biologically diverse protected coastal area of Guanacaste, Costa Rica.

Diagnosis. Carapace strongly compressed laterally, cervical groove located in posterior third of carapace, lateral margin of carapace with hepatic groove, linea thalassinica very short. Eyestalks triangular, obtuse apically, slightly separated one from each other apically. Antennular peduncle distinctly shorter than antennal peduncle. Scaphognathite of maxilla with spinulose border and elongated seta on posterior lobe about half length of scaphognathite. Mxp2 with epipod short and foliaceous; palp of endopod with about five acute spines on distal region. P1 unequal and dissimilar; larger cheliped with ventral margin of propodus, merus and ischium dentate; margin ventral of propodus and carpus of smaller cheliped ornamented with long tufts of setae. P5 dactylus twisted, forming a true dentate claw with distal section of propodus, latter armed with teeth which increase in size toward distal end. Plp1 of 2 articles, distal article broadly triangular, with small mesial lobe bearing hooks. Pleopods 2–5 with both rami bearing marginal slender cylindrical accessory respiratory filaments unsegmented. Outer uropodal ramus with strong longitudinal carinae, margin dentate, inner ramus with longitudinal dorsal ridge bearing 2 spines.

Description. Medium in size shrimp, carapace length (CL) = 5.4–12.4mm. Carapace oval in shape, strongly compressed laterally and without cardiac prominence. Cervical groove located in posterior third of carapace, lateral margin of carapace with hepatic groove, linea thalassinica very short extending posteriorly from orbit ( Fig. 1 A). Rostrum conspicuous, triangular shape, pointed downward ( Fig. 1 B). Eyestalks triangular, obtuse apically, slightly separated one from each other apically; cornea well formed, suboval, small, subterminal ( Fig. 1 B). Antennular (Al) peduncle distinctly shorter than antennal (A2) peduncle, reaching to distal margin of fourth antennal segment, antennular terminal segment about 1.5 times as long as penultimate; A2 scaphocerite lacking, article 4 slender and elongated about as long as three anterior segments ( Fig. 1 B), antennal flagellum about 2 times as long as peduncle antennal. Incisor process of mandible with four teeth on the mandible crest, two smaller located on molar base; palp of 3 articles with abundant setae on distal margin and one row of fine spines through lateral margin ( Fig. 1 C). Maxillule with distal endite thin and long, proximal short and broad, latter with long epipod and setae with dentate tips; palp thin with two long setae on tip ( Fig. 1 D). Proximal and distal endite of maxilla bilobed, external margin of both densely covered with setae; palp two-segmented; scaphognathite with spinulose border and elongated seta on posterior lobe about half length of scaphognathite ( Fig. 1 E). Maxilliped 1 with two strong and setose endites; endopod provided with digitiform projection; exopod larger than endopod, epipod elongated and strong ( Fig. 1 F). Maxilliped 2 with exopod well-developed, flagellum segmented, epipod short and foliaceous; palp of endopod with about five acute spines on distal region, half length of second segment, fourth segment 2.4 times as long as posterior segments ( Fig. 1 G). Exopod of Mpx3 extending to mesial zone of merus, latter with an acute spine on internal margin close to carpus-merus articulation, epipod reduced; propodus slightly larger than carpus; merus shorter than ischium ( Fig. 1 H), ischium with crista dentate on inner surface, row of teeth increasing in size toward distal end ( Fig. 1 I).

P1 unequal and dissimilar. Larger cheliped massive; dactylus and fixed finger armed with prominent teeth on internal surface, inner surface of fixed finger with five prominent rounded teeth one very conspicuous and two rows of smaller teeth; palm and dactylus similar in length; ventral margin of propodus with dentate border; carpus conical, half length of merus, armed with a hook on ventral margin; merus subovoid, dentate border on ventral margin of merus and ischium ( Fig. 2 A). Smaller cheliped slender and less massive than larger cheliped; dactylus armed with one rectangular conspicuous tooth, dactylus similar in length than immobile finger; fixed finger with prominent triangular tooth distally on cutting edge, palm 2.0 times as long as dactylus; insertion carpus-merus subtriangular; merus and carpus similar in length, margin ventral of propodus and carpus ornamented with long tufts of setae ( Fig. 2 B).

Pereopod 2 chelate; dactylus with setal tufts; movable finger armed with acute spines on distal end; internal edge of fixed finger armed with acute spines, cutting edges straight, long tufts of setae on ventral margin of propodus and carpus; carpus triangular in shape; merus with long setal rows restricted to the ventral margin, ventral margin of merus strongly convex ( Fig. 2 C). P3 subchelate, palm with notch, dactylus thick and short with two setal rows, propodus laterally flattened with ventral margin covered with dense setal tufts, carpus triangular in shape, both sides of merus convex ( Fig. 2 D). P4 slightly subchelate; dactylus digitiform; propodus with strong distal spine and rows of setal on dorsal margin; carpus subtriangular in shape, carpus-merus insertion incomplete; merus about 2.0 times as long as carpus ( Fig. 2 E). P5 dactylus twisted, forming a true dentate claw with distal section of propodus, latter armed with teeth which increase in size toward distal end ( Fig. 2 F); dactylus and distal section of propodus covered with dense setal tufts; dorsal margin of carpus rounded; merus similar in long than three posterior segments; ischium subtriangular ( Fig. 2 G).

Abdominal somites smooth, with irregular oblique tufts of setae through abdominal region; abdominal somite 1 with sclerotized anterodorsal lobe, posterior region of lobe articulated in last part of cephalothorax; abdominal somite 1 different in shape from remaining somites ( Fig. 1 A). Pleopod 1 in male of 1 article, distal article broadly triangular, with small mesial lobe bearing hooks ( Fig. 2 H). Pleopod 2 with rod-shaped setose appendix masculina and short free appendix interna ( Fig. 2 I). Pleopods 2–5 with both rami bearing marginal slender cylindrical accessory respiratory filaments unsegmented ( Fig. 2 I). Uropodal ramus rounded, outer uropodal ramus with strong longitudinal carinae, distal margin dentate, inner ramus with longitudinal dorsal ridge bearing 2 spines; lateral ridge of telson converge distally, slightly wider than longer, ornamented with long tufts of setal ( Fig. 2 J).

Habitat. The specimens were collected by hand, in the sand under rocks in the intertidal zone.

Colour. Carapace white, cardiac region pale salmon, without any kind of chromatophores. Pereopods l and 2 strongly calcified and white. Pereopods 3–5 white, transparent. Abdomen white except for a tint of pale salmon on lateral face. Tail fan and pleopods white.

Type locality. Islotes Mogos, Osa, Golfo Dulce (08°38?03”N - 83°09?51”W), southern Pacific coast of Costa Rica.

Distribution. Presently known only along the Pacific coast of Costa Rica.

Remarks. Callianidea mariamartae n. sp., and C. laevicauda from Caribbean Sea share some similarities i.e. very short linea thalassinica and maxilliped 3 with an acute spine on internal margin of the merus (between others morphological characters). However, the new species differs from C. laevicauda , among other aspects, in having (1) lateral margin of carapace with a distinct hepatic groove; (2) anterolateral carapace without vertical row of specialized setae in postantennal area; (3) seta on posterior lobe of maxilla about half length of scaphognathite (4) Mxp2 with acute spines on distal region of palp; (5) accessory respiratory filaments unsegmented; (6) outer uropodal ramus with strong longitudinal carinae ( C. laevicauda see Kensley & Heard 1991; p. 501–502; Fig. 3A, C; 4A, F, I). Callianidea mariamartae n. sp. differs from C typa from Indo Pacific region in having a linea thalassinica very short and pleopods filaments unsegmented. Callianidea typa is characterized by lacking any sign of a linea thalassinica and the presence of cylindrical pleopodal filaments with a constriction near the midpoint ( C. typa see Sakai 1992; p. 13, 15; Fig. 3A, 5H and Poore 1997; p. 350; Fig. 1 A).

Figures

FIGURE 1. Callianidea mariamartae n. sp. A, lateral view; B, anterior region of carapace; C, right mandible; D, right maxillule; E, right maxilla; F, right maxilliped 1, G, right maxilliped 2; H, right maxilliped 3; I, crista dentate on inner surface of merus Mxp 3. A, B, male holotype; C – H, male paratype. Scale bars equal 1.0 mm.

FIGURE 2. Callianidea mariamartae n. sp. A, major cheliped; B, minor chelipod; C, pereiopod 2; D, pereiopod 3; E, pereiopod 4; F, detail of dactylus pereiopod 5, G, pereiopod 5; H, pleopod 1 male; I, internal and external view pleopod 2 (AM, appendix masculine; AI, appendix internae); J, telson and uropods. A – F, H, male holotype; G, male paratype. Scale bars equal 1.0 mm.