Bathoxiphus ensiculus ( Jeffreys, 1877 )

Souza, Leonardo S., Caetano, Carlos Henrique S., Scarabino, Fabrizio & Costa, Paulo Márcio S., 2020, New records and a new species of Scaphopoda (Mollusca) from the southwestern Atlantic Ocean, Iheringia, Série Zoologia (e 2020023) 110, pp. 1-12 : 2-4

Bathoxiphus ensiculus ( Jeffreys, 1877)

( Figs 1–18 )

Dentalium ensiculus JEFFREYS, 1877:154 . Dentalium sigsbeanum DALL, 1881:38 . Dentalium ensiculus ― JEFFREYS,1882:660, pl. 49, fig.4; VERRILL,1885:432;

WATSON,1886 (not 1885 as cited by HENDERSON 1920):12, pl. 2, fig.

2; DALL, 1889:428, pl. 27, fig. 12; 1890:294. Dentalium (Bathoxiphus) ensiculus ― PILSBRY & SHARP,1897:121, pl. 7, figs.

7–10; DALL, 1927:17; EMERSON, 1952:6; ABBOTT,1974:387, fig. 4526. Bathoxiphus ensiculus ― CHISTIKOV,1983:183, pl. 1, figs. 1–5, pl. 4, fig.

5; STEINER & KABAT, 2004:588; GOFAS et al., 2017:8.

Type material. Syntypes: NORTH ATLANTIC: Porcupine expedition unknown sta.( NHMUK 1885.11.5.1344- 46,3 shells); Valorous expedition, 2652 m [originally as “1450 fms”]( NHMUK 1877.11.28.56a–c,3 shells); Valorous exp. sta. 12, 56°11ʼN37°41ʼW, 2652 m [originally as “1450 fms”] ( USNM 176126 , 16 shells); Valorous exp.sta. 16, 55°10ʼN 15°58ʼW, 3264 m [originally as “1785 fms”]( USNM 176131 , 1 shell); Porcupine exp. 1869 sta. 19, 54°53ʼN 10°56ʼW, 2487 m [originally as “1360 fms”]( USNM 176127 , 1 shell); Porcupine exp. 1869 sta. 42, 49°12ʼN 12°52ʼW, 1576 m [originally as “862 fms”]( USNM 176128 , 1 shell]; Porcupine exp. 1870 sta. 17, 39°42ʼN 9°43ʼW, 2003 m [originally as “1095 fms”]( USNM 176129 , 5 shells); Porcupine exp. 1870 sta. 16,39°55ʼN 9°56ʼW, 1818 m [originally as “994 fms”] ( USNM 176130 , 9 shells).

Type locality. A holotype, as well as a type locality, were not designated by JEFFREYS (1877). However, based on the list of examined syntypes, it can be assigned that the original description was based on samples collected from many places in the Northeast Atlantic, between 1576 and 3264 m. As we have not been able to examine all the syntypes, a precise type locality could not be determined.

Material examined. Syntypes NHMUK 1885.11.5.1344–46 and NHMUK 1877.11.28.56a–c. BRAZIL, Rio de Janeiro: Santos Basin, Alto de Cabo Frio sta. 9, 24°14 ʼ 56 ˮ S 41 ° 32 ʼ 11 ˮ W, 1900 m, coll. 2018 ( MNRJ 23600 , 1 shell); Santos Basin , Gato do Mato sta. 1, 25°01 ʼ 14 ˮ S 43°00 ʼ 56 ˮ W, 2050 m, coll. 2018 ( MNRJ 23601 , 1 shell); São Paulo: Santos Basin , Carcará East sta. 1, 25°23ʼ28ˮS 43°57ʼ40ˮW, 2100 m, coll. 16–22/i/2019 ( MNRJ 60839 , 2 shells); Santos Basin , Carcará East sta. 3, 25°23 ʼ 32 ˮ S 43°57 ʼ 45 ˮ W, 2100 m, coll. 16–22/i/2019 ( MNRJ 60826 , 1 shell); Santos Basin , Carcará East sta. 4, 25°23 ʼ 23 ˮ S 43°57 ʼ 45 ˮ W, 2100 m, coll. 16–22/i/2019 ( MNRJ 60823 , 2 shells); Santos Basin , Carcará East sta. 5, 25°23 ʼ 15 ˮ S 43°57 ʼ 29 ˮ W, 2100 m, coll. 16–22/i/2019 ( MNRJ 60821 , 1 shell); Santos Basin , Carcará East sta. 10, 25°24 ʼ 04 ˮ S 43°58 ʼ 16 ˮ W, 2100 m, coll. 16–22/i/2019 ( MNRJ 60832 , 1 shell) .

Distribution. Western Atlantic: Greenland; USA: Massachusetts, Delaware, Georgia, Florida ( DALL, 1890; HENDERSON, 1920); Mexico: Yucatan Strait ( DALL, 1881); Cuba ( HENDERSON, 1920); Puerto Rico ( EMERSON, 1952); Anguilla: Sombrero Island ( WATSON, 1886); St. Barts; Barbados; St. Vincent and Grenadines ( HENDERSON, 1920); Brazil: Rio de Janeiro, SÃo Paulo (this study). Eastern Atlantic: Ireland; Portugal ( JEFFREYS, 1877); Spain ( GOFAS et al., 2017); Namibia (?) ( STEINER & KABAT, 2004). Empty shells from 353 m to 3264 m.

Remarks. The type material of B. ensiculus consists of several syntypes housed in the collections of NHMUK ( Figs 1–12 ) and USNM. WARÉN (1980) and STEINER & KABAT (2004) did not locate the syntypes NHMUK 1877.11.28.56a– c, but the three shells were found in the present study (Tom White pers. commun.) and are figured here ( Figs 1–6 ). The syntypes from the USNM were not examined in the present study and a lectotype designation is postponed until it is possible to examine the complete type series of B. ensiculus .

Bathoxiphus ensiculus was originally described from several localities in the Northeast Atlantic ( JEFFREYS, 1877) and later VERRILL (1885) recorded for the first time this species from the Northwest Atlantic. It is currently known from both sides of the North Atlantic, with a restricted distribution to the northern hemisphere in the western Atlantic, and in the eastern side, it is reported from Ireland (northern hemisphere) to Namibia (southern hemisphere) by STEINER & KABAT (2004). The latter authors did not report the source of the record from the southeastern Atlantic and the occurrence of this species in this region needs confirmation.

In the present study, B. ensiculus is recorded in the southwestern Atlantic for the first time. The empty shells collected in the Southeast coast of Brazil at about 2100 m fit the morphology of the syntypes examined ( Figs 1–12 ) in having an elongated, strongly arched, laterally compressed shell, showing an over half apical notch in the anterior side of the apex ( Figs 13–18 ). The shells from Brazil are slightly smaller than the largest syntypes of B. ensiculus , but reach a strong curvature like them ( Tab.I).

Figures

Figs 1–12. Bathoxiphus ensiculus (Jeffreys, 1877). 1–6, syntypes (NHMUK 1877.11.28.56): 1, 2: same shell; 3, 4: same shell; 5, 6: same shell; 7–12, syntypes (NHMUK 1885.11.5.1344–46): 7, 8: same shell; 9, 10: same shell; 11, 12: same shell. 1, 3, 5, 7, 9, 11, entire shell, lateral view; 2, 4, 6, 8, 10, 12, detail of ventral aperture. Scale bars: 1, 3, 5, 7, 9, 11= 5 mm; 2, 4, 8, 10, 12= 1 mm; 6= 0.5 mm. Credits: K. Webb (NHMUK photographic unit).

Figs 13–18. Bathoxiphus ensiculus (Jeffreys, 1877). 13–17, MNRJ 60821, same shell; 18, MNRJ 60823. 13, 18, entire shell, lateral view; 14, entire shell, anterior view.15, detail of the apex; 16, detail of ventral aperture; 17, detail of dorsal aperture.Scale bars: 13, 14, 18= 5 mm; 15, 16= 0.5 mm; 17= 0.2 mm.