Arcoscalpellum epeeum, Chan, Benny K. K., Corbari, Laure, Rodriguez Moreno, Paula A. & Jones, Diana S., 2014

Chan, Benny K. K., Corbari, Laure, Rodriguez Moreno, Paula A. & Jones, Diana S., 2014, Two new deep-sea stalked barnacles, Arcoscalpellum epeeum sp. nov. and Gymnoscalpellum indopacificum sp. nov., from the Coral Sea, with descriptions of the penis in Gymnoscalpellum dwarf males, Zootaxa 3866 (2), pp. 261-276 : 263-269

publication ID	https://doi.org/ 10.11646/zootaxa.3866.2.5
publication LSID	lsid:zoobank.org:pub:66371FFC-45B2-47BF-98D1-33315EA8B4A8
DOI	https://doi.org/10.5281/zenodo.6136315
persistent identifier	https://treatment.plazi.org/id/03D587FC-8624-4E1D-FF25-FE1B6BAA5F64
treatment provided by	Plazi
scientific name	Arcoscalpellum epeeum
status	sp. nov.

Treatment

Arcoscalpellum epeeum sp. nov.

( Figs 2–6 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 )

Material examined. Holotype: MNHN-IU-2013-7431, 1 specimen, EBISCO Stn. (CP2579 New Caledonia, North Bellona, 20°21’S, 158°40’E, 14 Oct. 2005, depth: 440–455 m), CL 63 mm, CW 29 mm, PL 20 mm. Paratypes: MNHN-IU-2013-7432, 12 specimens, NORFOLK 1 Stn. DW1733 ( New Caledonia, Norfolk Ridge, 22°56’S, 167°15’E, 28 Jun. 2001, depth: 427–433 m), CL 22.95–27.15 mm, CW 14.28–17.33 mm, PL 7.11–11.98 mm; MNHN-IU-2013-8582, 1 specimen, NORFOLK 2 Stn. CP2146 ( New Caledonia, Isle of Pines, 22°50’S, 167°17’E, 4 Nov. 2003, depth: 518 m), CL 26.27 mm, CW 18.32 mm, PL 5.37 mm; MNHN-IU-2013-8583, 1 specimen, EBISCO Stn. DW2603 (Coral Sea, Chesterfield Plateau, 19°36’0”S, 158°43’0”E, 18 Oct. 2005, depth: 568–570 m), CL 33.05 mm, CW 21.91 mm, PL 4.76 mm; MNHN-IU-2013-8584, 10 specimens, NORFOLK 1 Stn. DW1734 ( New Caledonia, Norfolk Ridge, 22°53’S, 167°12’E, 28 Jun. 2001, depth: 403–429 m), CL 23.30–31.80 mm, CW 12.99–19.98 mm, PL 7.07–12.71 mm; MNHN-IU-2013-8585, 3 specimens, EBISCO Stn. DW2606 (Coral Sea, Chesterfield Plateau, 19°37’S, 158°42’E, 18 Oct. 2005, depth: 442–443 m), CL 24.53–32.39 mm, CW 12.33–20.63 mm, PL 12.95 mm, others PL broken; MNHN-IU-2013-8586, 5 specimens, EBISCO Stn. DW2610 (Coral Sea, Chesterfield Plateau, 19°34’S, 158°41’E, 19 Oct. 2005, depth: 486–494 m), CL 21.40–35.43 mm, CW 13.20–28.06 mm, PL 7.08–22.87 mm; MNHN-IU-2013-8587, 2 specimens, EBISCO Stn. DW2608 (Coral Sea, Chesterfield Plateau, 19°33’S, 158°40’E, 19 Oct. 2005, depth: 393–396 m), CL 25.96 mm, CW 18.86 mm, PL 7.15 mm; MNHN-IU-2013-8588, 3 specimens, EBISCO Stn. DW2613 (Coral Sea, Chesterfield Plateau, 19°37’S, 158°42’E, 19 Oct. 2005, depth: 519–522 m), CL 20.58–31.95 mm, CW 12.12–21.55 mm, PL all broken; MNHN- IU-2013-8589, 2 specimens, EBISCO Stn. CP2611 (Coral Sea, Chesterfield Plateau, 19°34’S, 158°41’E, 19 Oct. 2005, depth: 492–506 m), CL 32.97 mm, CW 26.31 mm, PL 18.14 mm; MNHN-IU-2013-8590, 1 specimen, EBISCO Stn. DW2607 (Coral Sea, Chesterfield Plateau, 19°33’S, 158°40’E, 18 Oct. 2005, depth: 400–413 m), CL 30.44 mm, CW 20.45 mm, PL 11.93 mm; MNHN-IU-2013-8591, 1 specimen, EBISCO Stn. DW2617 (Coral Sea, Chesterfield Plateau, Lansdowne, 20°6’S, 160°22’E, 20 Oct. 2005, depth: 427–505 m), CL 17.38 mm, CW 11.78 mm, PL 4.96 mm; MNHN-IU-2013-8592, 2 specimens, EBISCO Stn. DW2604 (Coral Sea, Chesterfield Plateau, 19°37’S, 158°440’E, 18 Oct. 2005, depth: 569–578), CL 31.86 mm, CW 20.33 mm, PL broken; MNHN-IU-2013- 8593, 4 specimens, NORFOLK 2 Stn. DW2155 ( New Caledonia, Isle of Pines, 22°52’S, 167°13’E, 5 Nov. 2003, depth: 453–455 m), CL 19.88–25.34 mm, CW 13.11–18.96 mm, PL 6.22–9.10 mm; MNHN-IU-2013-8594, 1 specimen, NORFOLK 2 Stn. CP2090 ( New Caledonia, Norfolk Ridge, Kaimon Maru Bank, 24°44’S, 168°07’E, 29 Oct. 2003, depth: 274–281 m), CL 27.61 mm, CW 17.32 mm, PL 14.13 mm; MNHN-IU-2013-8597, 5 specimens, NORFOLK 1 Stn. DW1734 ( New Caledonia, Norfolk Ridge, 22°53’S, 167°12’E, 28 Jun. 2001, depth: 403–429 m), CL 23.86–29.28 mm, CW 15.07–21.68 mm, PL 7.34–9.90 mm; MNHN-IU-2013-8598, 2 specimens, NORFOLK 2 Stn. DW2156 ( New Caledonia, Isle of Pines, 22°54’S, 167°15’E, 5 Nov. 2003, depth: 468–500 m), CL 25.58–26.50 mm, CW 15.58–18.87 mm, PL: broken. Other material examined: MNHN-IU-2013-13100, 2 specimens, SMIB 2 Stn. DW4 ( New Caledonia, Isle of Pines, Norfolk Ridge, 22°53'S, 167°13'E, 17 Oct. 1986, depth: 410–417 m); MNHN-IU-2013-13101, 4 specimens, SMIB 2 Stn. DW12 ( New Caledonia, Isle of Pines, Norfolk Ridge, 22°53'S, 167°14'E, 18 Oct. 1986, depth: 445–460 m); MNHN-IU-2013-13102, photo, 1 specimen (peduncle missing), SMIB 2 Stn. DW13 ( New Caledonia, Isle of Pines 22°52'S, 167°13'E, 18 Oct. 1986, depth: 427–454 m); MNHN-IU-2013-13103, 1 specimen, SMIB 4 Stn. DW64 ( New Caledonia, Norfolk Ridge, 22°55’S, 167°16’E, 10 Mar. 1989, depth: 455–460 m); MNHN-IU-2013-13104, 1 specimen, SMIB 4 Stn. DW65 ( New Caledonia, Norfolk Ridge, 22°55’S, 167°14’E, 10 Mar. 1989, depth: 400–420 m); MNHN-IU-2013-13105, 1 specimen, BIOCAL Stn. DW44 (Loyalty Islands, 22°47’S, 167°14’E, 30 Aug. 1985, depth: 440–450 m); MNHN- IU-2013-13106, 1 specimen, MUSORSTOM 6 Stn. DW460 (Loyalty Islands, 21°01’72”S, 167°31’45”E, 20 Feb.1989, depth: 420 m); MNHN-IU-2013-13107, 3 specimens, MUSORSTOM 4 DW222 ( New Caledonia, Grande-Terre, 22°58’S, 167°33’E, 30 Sept. 1985, depth: 410–440 m); MNHN-IU-2013-13108, 3 specimens, MUSORSTOM 4 DW223 ( New Caledonia, Grande-Terre, 22°57’S, 167°30’E, 30 Sep. 1985, depth: 545–560 m); MNHN-IU-2013-13109, 3 specimens, MUSORSTOM 4 Stn. DW229 ( New Caledonia, Grande-Terre, 22°52’S, 167°13’E, 30 Sep. 1985, depth: 445–460 m); MNHN-IU-2013-13110, 2 specimens, MUSORSTOM 4 Stn. DW 230, ( New Caledonia, Grande-Terre, 22°52’S 167°12’ E, 30 Sep. 1985, depth: 390–420 m); MNHN-IU-2013- 13111, 5 specimens, MUSORSTOM 5 Stn. DW355 (Coral Sea, Chesterfield Plateau, 19°36’S, 158°43’E, 18 Oct. 1986, depth: 580 m); MNHN-IU-2013-13112, 2 specimens, MUSORSTOM 5 Stn. DW355 (Coral Sea, Chesterfield Plateau, 19°36’S, 158°43’E, 18 Oct. 1986, depth: 580 m); MNHN-IU-2013-13113, 2 specimens, no data, New Caledonia, MNHN-IU-2013-13114, 5 specimens, BATHUS 2 Stn. DW718 ( New Caledonia, 22°47’S, 167°14’E, 11 May 1993, depth: 430–436 m); MNHN-IU-2013-13115, many specimens, BATHUS 2 Stn. DW719 ( New Caledonia, 22°48’S, 167°16’E, 11 May 1993, depth: 444–455 m); MNHN-IU-2013-13116, 2 specimens (1 ovigerous), BATHUS 2 Stn. DW720 ( New Caledonia, 22°52’S, 167°16’E, 11 May1993, depth: 530–541 m); MNHN-IU-2013-13117, BATHUS 2 Stn. DW729 ( New Caledonia, 22°52’S, 167°12’E, 12 May 1993, depth: 349–400 m); MNHN-IU-2013-13118, 1 specimen, SMIB 8 Stn DW187 ( Norfolk Ridge, Banc Aztèque, 23°18’S, 168°06’E, 31 Jan. 1993; depth: 390–540 m); MNHN-IU-2013-13119, 1 specimen, SMIB 8 Stn DW193 ( New Caledonia, Isle of Pines, 22°59’S 168°19’E, 0 1 Feb. 1993; depth: 500–508 m); MNHN-IU-2013-13120, 1 specimen, MUSORSTOM 8 Stn. CP984 ( Vanuatu, 19°20’S, 169°26’E, 23 Sep. 1994, depth: 480–544 m); MNHN- IU-2013-13121, 1 specimen, MUSORSTOM 8 Stn. DW1061 ( Vanuatu, 16°15’S, 167°20’E, 0 2 Oct. 1994, depth: 458–512 m).

Diagnosis. Fourteen fully calcified capitular plates, surfaces pubescent, carina sword-shaped, long, narrow, straight, apex sharp, 1/4 of total carinal length extending beyond apices of terga.

Description of holotype. Female. Fourteen fully calcified, white plates, surfaces pubescent, covered by pale yellow, short setae ( Fig. 2 View FIGURE 2 A–C). Tergum quadrangular, carinal margin longest, 1/3 of distal end of carinal margin bent away from carina, occludent margin straight, umbo apical, apex acute ( Fig. 2 View FIGURE 2 A–C). Scutum quadrangular, occlusal margin slightly convex, tergal margin concave, lateral and basal margins straight, umbo apical ( Fig. 2 View FIGURE 2 A). Upper latus triangular ( Fig. 2 View FIGURE 2 A), tergal margin convex, scutal and lateral margins straight, umbo apical ( Fig. 2 View FIGURE 2 A). Inframedian latus small, triangular, umbo apical. Rostrolatus quadrilateral, flattened, width 4 times height ( Fig. 2 View FIGURE 2 A). Carinolatus quadragular, umbo recurved ( Fig. 2 View FIGURE 2 A). Carina very long, narrow, sword-shaped, apex acute, carina extending beyond tergum about 1/4 its total length ( Fig. 2 View FIGURE 2 A, C). Rostrum minute, almost covered by paired rostral-laterals ( Fig. 2 View FIGURE 2 B, E).

Maxilla bilobed ( Fig. 3 View FIGURE 3 A), serrulate setae distributed along cutting edge ( Fig. 3 View FIGURE 3 B), dense setae apically. Maxillule cutting edge without notch ( Fig. 3 View FIGURE 3 C), cutting edge wide, with 20 or more cuspidate setae ( Fig. 3 View FIGURE 3 C). Mandible with 3 equally spaced teeth ( Fig. 3 View FIGURE 3 D), inferior angle blunt, with about 12 cuspidate setae ( Fig. 3 View FIGURE 3 D, E). Mandibular palp narrow ( Fig. 3 View FIGURE 3 F), elongated, serrulate setae on superior margin and distally ( Fig. 3 View FIGURE 3 G), inferior margin naked. Labrum bullate, cutting margin slightly concave, cutting edge smooth ( Fig. 3 View FIGURE 3 H).

Cirrus I short, separated from cirri II–VI, rami subequal ( Fig. 4 View FIGURE 4 A); anterior ramus shorter, flattened, 10 ovalshaped segments; posterior ramus longer, slender, 17-segmented ( Fig. 4 View FIGURE 4 A); both rami bearing serrulate setae ( Fig. 4 View FIGURE 4 B). Cirri II–VI long, slender, similar in length. Cirrus II with anterior ramus 21-segmented, posterior 28- segmented ( Fig. 4 View FIGURE 4 C); intermediate segments of both rami with 4 pairs of long, serrulate setae and 1 pair of short, serrulate setae ( Fig. 4 View FIGURE 4 D). Cirrus III with anterior ramus 24-segmented, inner ramus 24-segmented (broken) ( Fig. 4 View FIGURE 4 E); intermediate segments of both rami bearing 4 pairs of long, serrulate setae and 1 pair of short, serrulate setae ( Fig. 4 View FIGURE 4 F). Cirrus IV with anterior ramus 25-segmented, posterior ramus 23-segmented ( Fig. 4 View FIGURE 4 G), intermediate segments of both rami bearing 3 pairs of long serrulate setae and 1 pair of short serrulate setae ( Fig. 4 View FIGURE 4 H). Cirrus V, anterior ramus 24-segmented (broken at distal ends), posterior ramus 25-segmented (broken at distal ends) ( Fig. 5 View FIGURE 5 A). Cirrus VI, anterior ramus 23-segmented, posterior ramus 24-segmented (distal ends of both rami broken) ( Fig. 5 View FIGURE 5 C), intermediate segments of both rami of cirri V and VI bearing 4 pairs of long serrulate setae and 1 pair of short, serrulate setae ( Fig. 5 View FIGURE 5 B, D). Caudal appendage short, 1-segmented, distal end blunt with bundle of serrulate setae, length less than height of basal segment of pedicle of cirrus VI ( Fig. 5 View FIGURE 5 E, F).

Dwarf males absent from holotype; present in paratypes, embedded in paired, oval-shaped receptacles located at inner edge of scutal plates, just above adductor muscles ( Fig. 2 View FIGURE 2 D, F), 2 or 3 dwarf males in each receptacle ( Fig. 2 View FIGURE 2 F). Dwarf males with shell plates absent, peanut shaped, anterior and posterior ends swollen, middle portion narrowed ( Fig. 5 View FIGURE 5 G), denticles arranged in fan shape, located on surface ( Fig. 5 View FIGURE 5 H); no penis observed extending from aperture.

Distribution. New Caledonia and Vanuatu.

Etymology. The species is named for the sword-shaped carina, resembling a French word “épée”.

Remarks. Of the Arcoscalpellum species described to date, no species have been reported with a long, sharp, sword-like carina that extends much beyond the apices of the terga. A long, sharp carina is present during the ontogeny of Arcoscalpellum epeeum sp. nov., being relatively straighter in younger specimens and then becoming curved inward in larger individuals ( Fig. 6 View FIGURE 6 ).

The genus Arcoscalpellum is one of the most diverse of the scalpellid genera. Currently, 44 species are recognised in the genus, with one species, Arcoscalpellum spinum Newman & Ross, 1998 , classified under the subgenus Vetecroscalpellum Newman & Ross, 1998. Arcoscalpellum epeeum sp. nov. occurs in the Coral Sea, in the waters of New Caledonia and Vanuatu, but was not present in the extensive barnacle collections made by French expeditions off the Solomons, Tonga, Papua New Guinea and Fiji, or Madagascar in the Indian Ocean (about 1305 specimens corresponding to 300 localities throughout the Indo-Pacific).

Currently, there are no community level studies to examine barnacles from seamounts. The recent rich collections in the Tropical Deep-Sea Benthos programme will open up future research initiatives to carry out community based comparisons of deep-sea barnacles from seamounts and adjacent slope habitats.