Solinca aulix, Colavite, Jessica, Windsor, Amanda & Santana, William, 2019

Colavite, Jessica, Windsor, Amanda & Santana, William, 2019, Three new species and a new genus of majoid crabs from the eastern Pacific (Decapoda, Brachyura), ZooKeys 825, pp. 1-24 : 14-19

Solinca aulix sp. n. Figures 6 A–F, 7 D–G

Holotype.

Peru, off Paita, Piura, Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, stn 627-A, 05°01' / 05°02'S; 81°25'/ 81°24'W, 03.vi.1966, Smithsonian Oceanographic Sorting Center coll., 200-311 m, male holotype, cl 37.3 mm, cw 28.2 mm (USNM 1462734).

Paratypes.

Peru, off Paita, Piura, Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, stn 627-A, 5°01' / 05°02'S; 81°25' / 81°24'W; 3.vi.1966, Smithsonian Oceanographic Sorting Center coll., 200-311 m, 1 female (MZUSP 38891), 1 male (MZUSP 38892). Idem, 1 female, cl 39.5, cw 29.8 mm, 1 male and 1 juvenile (USNM 1462685). Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, cruise 16, stn 635-A, 06°45'S; 80°93'W, 5.ix.1966, Smithsonian Oceanographic Sorting Center coll., 160 m, 1 male, cl 40.31 mm, cw 32.05 mm (USNM 1462673).

Material examined.

Ecuador, Gulf of Guayaquil, northwest of Tumbes, Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, stn 768, 03°39'S; 80°41'W, 10.ix.1966, Smithsonian Oceanographic Sorting Center coll., 13 m, 1 juvenile female (USNM 1460378). Peru, off Paita, Piura, Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, stn 627-A, 05°01' / 05°02'S; 81°25' / 81°24'W, 03.vi.1966, Smithsonian Oceanographic Sorting Center coll., 200-311 m, 6 males, 3 juveniles males, 5 females, 1 ovigerous females (USNM 1462735), off Isla Lobos de Tierra, Southeast Pacific Biological Oceanographic Project (SEPBOP), R/V Anton Bruun, stn 635A, 06°27' / 06°23'S; 80°56' / 80°55'W, 05.vi.1966, Smithsonian Oceanographic Sorting Center coll., 160 m, 4 males, 7 ovigerous female (USNM 1462736).

Comparative material.

Chorilia longipes Dana, 1851. Canada, British Columbia, Queen Charlotte Islands, Port Hardy, United States Fish Commission, R/V Albatross, stn 2862, 50°49'N; 127°36'W, 1.ix.1888, 3 males, 5 females, 2 juveniles (USNM 15497). United States of America, Alaska, vicinity of Yes Bay, Behm Canal, east end Square Island, Spacious Bay S, 48W, 19 miles, 130-193 m, 8.vii.1903, 2 males, 2 females (USNM 31637). California, Farallon Island, R/V Velero, EPA Farallon Study Expedition, stn 1, R Carney coll. det., 17 specimens (USNM 1420706). California, NE of Santa Barbara Island, Channel Islands, United States Fish Commission, R/V Albatross, stn 4416, 591-819 m, 12.iv.1904, 13 specimens (USNM 46534).

Pugettia nipponensis Rathbun, 1932. Japan, Honshu Island, Doumiki-saki, R/V Albatross, stn 3771, 05.vi.1900, MJ Rathbun det., male holotype (USNM 48254).

Pugettia quadridens (De Haan, 1839). South Korea, Dolsan Island, Sea of Japan, 1 juvenile, DNA only (ULLZ 13538). Japan, Honshu Island, Suruga Bay, Omae Zaki, R/V Albatross, stn 3730, 16.v.1900, MJ Rathbun det., 1 male, 1 female (USNM 49925).

Scyramathia vesicularis Rathbun, 1907. Ecuador, South of Española, Galapagos Islands, 1°50'83"S; 89°58'33"W, R/V Albatross, stn 4642, 549 m, 7.xi.1904, MJ Rathbun det., male holotype (USNM 32860).

Scyra acutifrons Dana 1851. United States of America, Washington, Port Orchard, Puget Sound, vi.1889, OB Johnson coll., MJ Rathbun det., 8 males, 3 females (USNM 14966). Washington, Lopez Island, Rock Point, 48N; 122W, G Paulay coll., 22.vi.2007, DNA only (UF 11955).

Type-locality.

Peru, off Paita, Piura, 05°01'S to 05°02'S; 81°25'W to 81°24'W, 200-311 m.

Diagnosis.

Same as for the genus.

Description.

Carapace distinctly sub-circular in outline, surface prominently inflated, particularly swollen at protogastric and branchial regions. Urogastric region compressed by metabranchial lobes into a deep furrow. Four spines - mesogastric, metagastric, cardiac, intestinal - along dorsal carapace midline. Dorsal carapace sparsely covered with long simple and hooked setae. Gastric region with two lateral spines, one protogastric, one mesogastric. One hepatic, one small sub-hepatic spines. Branchial region with four protobranchial spines; mesobranchial with four long, five shorter spines; two metabranchial, one lateral, one mesial spine above metabranchial lobe. Mesial border of branchial region with one distinct spine near the furrow, one cardiac and one intestinal spine. Branchiostegal region with two rows of spines, superior row with five strong, acute spines along most of posteroinferior half of molt line, at least five smaller spines in lower row. Gastric region delimited by shallow grooves; branchial, cardiac, intestinal regions delimited by well-marked grooves. Gastric, branchial regions with few tubercles or small spines. Pterygostomial region sub-triangular with five acute spines, few tubercles on lateral margin, smooth medially, inflated, visible in dorsal view. Thoracic pleurites V–VII gymnopleura.

Rostrum bifurcated, short, straight, more divergent in juveniles. Supraorbital spine acute, pointed forward. Postorbital spine long, curved beyond eyes. Eyes not retractable. Basal article of antenna narrow, second article long with two spines, one anterolateral, one posterolateral; one small sub-orbital spine in line with antennal gland. Antennae exceeding the rostral length, visible dorsally, flagellum short, thin; third antennal article longest; third and fourth antennal articles thick, cylindrical. Antennular fossae longitudinally ovate, longer than wide; interantennular septum long compressed laterally, forming ventrally-directed keel.

Epistome narrower than antennular fossae, anterior margin smooth, posterior margin crenulated; antennal gland open in epistome. Endostome with two obliquely prominent, longitudinal, very curved endostomial ridges. Buccal field sub-rectangular, longer than wide, narrower at posterior edge with smooth anterolateral angles.

Third maxillipeds covering buccal frame posteriorly, incompletely covering in anterior margin. Exopod long, nearly reaching distal margin of merus; ventral face with small process extending to posterolateral margin of merus. Ischium distinctly longer than broad, dorsal face smooth, deeply sculpted; crista dentata with very small, rounded teeth. Merus slightly longer than half of ischium, anteromesial border partially covering the propodus; anterior margin deeply incised, anterolateral margins slightly expanded, rounded. Palp cylindrical, slightly overreaching ischiomeral suture. Carpus, propodus and dactylus smooth; Propodus short, dactylus long and thin, with row of long setae on the distal margin. Male chelipeds equal, long, strong; merus, carpus and propodus sculpted by distinct sulcus in lateral and mesial faces; ischium smooth; merus armed with four dorsal spines, two smaller ventral spines; carpus with 3-4 blunt tubercles; propodus smooth; dactylus and fixed finger smooth, with same size as palm, cutting edges with sub-equal teeth in distal half, distinct proximal tooth in larger males; juvenile males and females fingers without gap.

P2-P5 long, slender, cylindrical, armed with distinct spine in distal margin of merus. P2 much longer than cheliped; P3-P5 progressively decreasing in length. Females with long, slender chelipeds. All legs covered with sparse, long simple setae.

Male thoracic sternite I-IV fused, broadly triangular, smooth; posterior half strongly sloping down in ventral view, forming a carina along lateral margin of telson. Sterno-pleonal cavity longer than telson, leaving gap between telson and anterior margin. Male sternites V–VII smooth; sternite VIII extending laterally beyond sterno-pleonal cavity, visible in ventral view. Margin of male episternites IV–VII smooth; female episternites IV–VII smooth, densely covered with small pubescence.

Male pleonal somites I–VI, telson free, smooth, slightly raised medially forming a low longitudinal ridge; first somite with distinct spine. Female pleonal somites I–IV, telson free; pleon markedly arched covering entire sterno-pleonal cavity; second somite with a distinct tubercle, sometimes forming a spine. Telson sub-triangular, terminating in rounded apex in males; female telson transversely oval.

First gonopod longer than thoracic sternal suture IV-V, straight proximally and medially, distinctly curved inwards sub-distally, convergent anteriorly; apical plate curved down with three well-pronounced lobes. Mesial lobe small, densely spinulate, curving toward sternal margin; distal lobe bilobed, long, tip rounded upwards; lateral lobe shorter than distal lobe, curved upward. G2 slender, straight, about 1/4 of G1 total length.

Distribution.

Ecuador, from Tumbes to Peru, Isla Lobos de Tierra at depths between 13 to 311 m.

Etymology.

The specific epithet aulix is the feminine Latin noun for “furrow” or “sulcus”, and alludes to the furrow in the intestinal region formed by the junction of the highly inflated branchial regions.

Remarks.

Solinca aulix can be distinguished from Chorilia longipes by a unique set of characters, which include: (i) rostral spines of Solinca aulix shorter than C. longipes (Fig. 6A, B, G); (ii) postorbital spines long, curved beyond eyes in Solinca (vs. truncated postorbital process curved medially in C. longipes ) (Fig. 6A, B, G); (iii) protogastric and branchial regions distinctly swollen in Solinca aulix (vs. protogastric and branchial regions weakly swollen in C. longipes ) (Fig. 6A, B, G); (iv) urogastric region compressed by metabranchial regions forming a furrow in Solinca aulix (vs. urogastric region not compressed and with some tubercles in C. longipes ) (Fig. 6A, B, G); (v) anterolateral border of the merus of the third maxilliped rounded in Solinca aulix (vs. anterolateral border of the merus of the third maxilliped pointed in C. longipes ) (Fig. 6C, D, H); (vi) pterygostomial region inflated, visible in dorsal view in Solinca aulix (vs. pterygostomial region not inflated and not visible in dorsal view in C. longipes ) (Fig. 6C, D, H); (vii) third and fourth antennal articles short and cylindrical in Solinca aulix (vs. third and fourth antennal articles long and flattened in C. longipes ); and (viii) G1 slightly overreaching the thoracic sternal suture IV-V in Solinca aulix (Fig. 7 D–G) (vs. G1 distinctly overreaching the thoracic sternal suture IV-V in C. longipes ).