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Genus Aclis Lov��n, 1846 TYPE SPECIES. ��� Alvania supranitida S. V. Wood, 1842, by monotypy., Published as part of Ortega, Jos�� Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, pp. 513-551 in Zoosystema 41 (26) on page 526, DOI: 10.5252/zoosystema2019v41a26, http://zenodo.org/record/3726028

Discaclis canariensis Moolenbeek & Waren, 1987 (Fig. 11 A-C) MATERIAL EXAMINED. ��� 1 sh., DW133., Published as part of Ortega, Jos�� Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, pp. 513-551 in Zoosystema 41 (26) on page 528, DOI: 10.5252/zoosystema2019v41a26, http://zenodo.org/record/3726028, {"references":["MOOLENBEEK R. G. & WAREN A. 1987. - A new genus and species of Aclididae from off Tenerife, Canary Islands. Bulletin, Zoologisch Museum, Universiteit van Amsterdam 11 (3): 21 - 23. https: // www. repository. naturalis. nl / document / 549145. Accessed 12 November 2019."]}

Genus Discaclis Moolenbeek & Warén, 1987 TYPE SPECIES. — Discaclis canariensis Moolenbeek & Warén, 1987, by original designation.

Discaclis lamellata n. sp. (Fig. 11 D-J) urn:lsid:zoobank.org:act: E31801E2-E7D1-4E48-BDEF-5CCE831C057A TYPE MATERIAL. ��� Holotype. sh., MNHN-IM-2000-34257. Paratypes. 16 sh., MNHN-IM-2000-34258 from SEAMOUNT 2, DW130. TYPE LOCALITY. ��� Off NW Gran Canaria, 28��08.95���N, 15��53.11���W / 28��09.06���N, 15��52.92���W, 655- 660 m. ETYMOLOGY. ��� An adjective formed from the Latin lamella, a small blade, alluding to the lamellae inside the umbilicus. DESCRIPTION Shell very small, with a low spire and a blunt, protruding apex and with a deep and rather wide umbilicus. Larval shell globular, smooth and glossy, consisting of about 1 1/4 whorls with diameter 320 to 330 ��m, demarcated from teleoconch by a distinct scar (difficult to see in optical microscopy due to transparency, conspicuous under SEM). Teleoconch of 1 1/4 whorl in specimens about 0.9 mm in diameter, up to 2 1/4 whorls in the largest specimens, with a narrow subsutural keel running very close to the suture and giving it a channelled aspect, with another blunt keel delimiting the abapical area around the umbilicus. Sculpture of numerous indistinct growth lines and, on the subsutural keel, of microscopic spiral striae. Within the umbilicus, 7-8 raised lamellae corresponding to earlier positions of outer lip. Aperture distinctly opisthocline, strongly expanded and flaring, especially in lower part prolonging the columellar edge. Outer lip not thickened. Maximum diameter (including the flaring lip) 0.9 to 1.3 mm (holotype 0.75 mm height �� 1.0 mm diameter). REMARKS Discaclis lamellata n. sp. differs from the only species of the genus known so far, D. canariensis (Fig. 11 A-C), in being twice as high with the same diameter, in having a considerably narrower umbilicus, and in having raised lamellae inside the umbilicus, which represent former stages of growth of the apertural lip. Discaclis canariensis is a shallow-water species with a type locality at 125 m and a record as shallow as 12 m in a submarine cave (Mart��nez et al. 2005). The specimen from Madeira figured by Segers et al. (2009: pl. 14, fig. 5) is more similar to Discaclis lamellata n. sp. (albeit larger, 1.5 mm) than to Discaclis canariensis; it is stated to originate from only 30 m depth but the authors suspect that it could be ���of subfossil origin���. It is possibly a third, different species, or alternatively Discaclis lamellata n. sp. is not a deep-sea species but the shells collected here have been transported downslope., Published as part of Ortega, Jos�� Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, pp. 513-551 in Zoosystema 41 (26) on page 528, DOI: 10.5252/zoosystema2019v41a26, http://zenodo.org/record/3726028, {"references":["MARTINEZ A., NUNEZ L., MONTERROSO O. & NUNEZ J. 2005. - Tanatocenosis de moluscos gasteropodos en sedimentos de una cueva submarina de la costa oeste de Tenerife (Islas Canarias). Revista de la Academia Canaria de Ciencias 16 (4): 161 - 177. https: // biodiversitylibrary. org / page / 42368487","SEGERS W., SWINNEN F. & DE PRINS R. 2009. - Marine Molluscs of Madeira. Snoeck Publishers, Heule, Belgium, 612 p."]}

Genus Aclis Lovén, 1846 TYPE SPECIES. — Alvania supranitida S. V. Wood, 1842, by monotypy.

Genus Discaclis Moolenbeek & War��n, 1987 TYPE SPECIES. ��� Discaclis canariensis Moolenbeek & War��n, 1987, by original designation., Published as part of Ortega, Jos�� Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, pp. 513-551 in Zoosystema 41 (26) on page 528, DOI: 10.5252/zoosystema2019v41a26, http://zenodo.org/record/3726028, {"references":["MOOLENBEEK R. G. & WAREN A. 1987. - A new genus and species of Aclididae from off Tenerife, Canary Islands. Bulletin, Zoologisch Museum, Universiteit van Amsterdam 11 (3): 21 - 23. https: // www. repository. naturalis. nl / document / 549145. Accessed 12 November 2019."]}

Aclis attenuans Jeffreys, 1883 (Fig. 10 A-F) MATERIAL EXAMINED. — 6 sh., SEAMOUNT 2, DW130. — 7 sh., Alboran Sea, Djibouti Banks, 36°21.08’N,‰ 3°58.58’E / 36°21.06’N, 3°58.07’E, 349-365 m, Spanish Institute of Oceanography cruise DP0409, haul BT04. — 1 sh., Gulf of Cadiz, Gazul mud volcano, 36°33,6’N 6° 56.3’W / 36°33.7’N, 6°56,3’ W, 428 m, cruise INDE- MARES CHICA 0610, haul DA11. REMARKS Bouchet & Warén (1986) recognized three similar species in deep water of the Atlanto-Mediterranean area: Aclis walleri Jeffreys, 1867 described from off Shetland (140 m), Aclis attenuans Jeffreys, 1883 described from off Crete (70- 120 fathoms = 128-219 m) and Aclis sarsi Dautzenberg & H. Fischer, 1912 described from off Norway (440 m). The Mediterranean A. attenuans differs from the Atlantic A. walleri in being smooth, without the axial riblets of A. walleri, in having a smaller (2-3 mm vs 4-5 mm high) and broader shell. Aclis sarsi differs from both in having only one protoconch whorl instead of more than two in the other two species Bouchet & Warén further reported a single shell from the Canaries as probably representing a new species, but refrained from describing it as the specimen was not in good enough condition. It was stated as having “the same kind of apical whorls as A. sarsi but the shape is similar to A. attenuans ”. The SEAMOUNT 2 material contains additional shells of the same Canarian species but this (including the specimen figured by Bouchet & Warén) has a little more than two protoconch whorls and is therefore similar to Aclis attenuans and does not have the paucispiral protoconch of Aclis sarsi. Admittedly, the Canarian specimens are slightly larger (3.7 mm instead of usually less than 3 mm for Mediterranean specimens) and the protoconch is also slightly larger in proportion, but are here taken as a range extension of Aclis attenuans and new record to Canary Islands waters.

Aclis attenuans Jeffreys, 1883 (Fig. 10 A-F) MATERIAL EXAMINED. ��� 6 sh., SEAMOUNT 2, DW130. ��� 7 sh., Alboran Sea, Djibouti Banks, 36��21.08���N,��� 3��58.58���E / 36��21.06���N, 3��58.07���E, 349-365 m, Spanish Institute of Oceanography cruise DP0409, haul BT04. ��� 1 sh., Gulf of Cadiz, Gazul mud volcano, 36��33,6���N 6�� 56.3���W / 36��33.7���N, 6��56,3��� W, 428 m, cruise INDE- MARES CHICA 0610, haul DA11. REMARKS Bouchet & War��n (1986) recognized three similar species in deep water of the Atlanto-Mediterranean area: Aclis walleri Jeffreys, 1867 described from off Shetland (140 m), Aclis attenuans Jeffreys, 1883 described from off Crete (70- 120 fathoms = 128-219 m) and Aclis sarsi Dautzenberg & H. Fischer, 1912 described from off Norway (440 m). The Mediterranean A. attenuans differs from the Atlantic A. walleri in being smooth, without the axial riblets of A. walleri, in having a smaller (2-3 mm vs 4-5 mm high) and broader shell. Aclis sarsi differs from both in having only one protoconch whorl instead of more than two in the other two species Bouchet & War��n further reported a single shell from the Canaries as probably representing a new species, but refrained from describing it as the specimen was not in good enough condition. It was stated as having ���the same kind of apical whorls as A. sarsi but the shape is similar to A. attenuans ���. The SEAMOUNT 2 material contains additional shells of the same Canarian species but this (including the specimen figured by Bouchet & War��n) has a little more than two protoconch whorls and is therefore similar to Aclis attenuans and does not have the paucispiral protoconch of Aclis sarsi. Admittedly, the Canarian specimens are slightly larger (3.7 mm instead of usually less than 3 mm for Mediterranean specimens) and the protoconch is also slightly larger in proportion, but are here taken as a range extension of Aclis attenuans and new record to Canary Islands waters., Published as part of Ortega, Jos�� Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, pp. 513-551 in Zoosystema 41 (26) on page 526, DOI: 10.5252/zoosystema2019v41a26, http://zenodo.org/record/3726028, {"references":["BOUCHET P. & WAREN A. 1986. - Revision of the Northeast Atlantic bathyal and abyssal Aclididae, Eulimidae, Epitonidae (Mollusca, Gastropoda). Bollettino Malacologico supplement 2: 297 - 576. https: // doi. org / 10.5962 / bhl. title. 140762"]}

Discaclis canariensis Moolenbeek & Waren, 1987 (Fig. 11 A-C) MATERIAL EXAMINED. — 1 sh., DW133.

Ortega, José Rafael, Gofas, Serge (2019): The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca. Zoosystema 41 (26): 513-551, DOI: 10.5252/zoosystema2019v41a26

The marine microgastropod genus Scalaronoba Powell, 1927 (Gastropoda: Aclididae?) is recorded from Australia for the first time, with the new species Scalaronoba kryptopleurakia n. sp. and Scalaronoba arenula n. sp. described from central Victoria. Three other indeterminate Victorian specimens are illustrated and discussed. These are the first records for the genus outside New Zealand. The uncertainty of the familial placement of Scalaronoba is discussed. These species are noted as being amongst the smallest gastropods to be recorded from Victorian waters. http://www.zoobank.org/urn:lsid:zoobank.org:pub:98860E57-6EC0-4F15-93D7-34A823E41E07

macrostoma, Aclis Barros, Lima & Francisco, 2007 Aclis macrostoma Barros, Lima & Francisco, 2007: 62–63 (figs 1–6). Gastropoda, Aclididae Holotype: MZSP 77988. Paratype 1: MZSP 77989. Paratypes 2 (2 spc): MZSP 77990. Localities: Brazil, off Rio Grande do Norte, continental slope off northeastern Brazil, muddy bottom, D-26, 06°14'04" S, 34°52'33" W, 510 m depth, 26 Nov. 2001; 1) muddy bottom, D-23, 04°51'00" S, 35°06'46" W, 375 m, 24 Nov. 2001; 2) muddy bottom, D-27, 06°14'24" S, 34°52'06" W, 500 m, 26 Nov. 2001. Preservation: Dry.

watsoni, Aclis Barros, Lima & Francisco, 2007 Aclis watsoni Barros, Lima & Francisco, 2007: 65���67 (figs 7���9). Gastropoda, Aclididae Holotype: MZSP 77991. Paratypes 1 (3 spc): MZSP 77992. Paratypes 2 (4 spc): MZSP 77993. Localities: Brazil, off Sergipe, continental slope, 10��41.4'00" S, 36��18.7'00" W, 365 m depth; 1) muddy bottom, 10��41.4'00" S, 36��18.7'00" W, 365 m, 28 Oct. 2000; 2) muddy bottom, 11��35.5'00"S, 37��12.3'00"W, 510 m, 30 Oct. 2000. Preservation: Dry., Published as part of Cavallari, Daniel C., Dornellas, Ana Paula S. & Simone, Luiz Ricardo L., 2016, Second annotated list of type specimens of molluscs deposited in the Museu de Zoologia da Universidade de S��o Paulo, Brazil, pp. 1-59 in European Journal of Taxonomy 213 on page 52, DOI: 10.5852/ejt.2016.213, http://zenodo.org/record/3840125, {"references":["Barros J. C. N., Lima S. F. & Francisco J. A. 2007. Two new species of Aclis (Mollusca: Gastropoda: Aclididae) from the continental slope of northeast Brazil. Zootaxa 1614: 61 - 68."]}

An alphabetical list of 352 type lots of molluscs housed in the Museu de Zoologia da Universidade de São Paulo is presented following the standards of the previous list by Dornellas & Simone (2011), with a few adjustments. Important items listed herein include types of species described after the previous compilation, as well as recently acquired paratypes of Asian Pomatiopsidae and Diplommatinidae (Gastropoda) taxa described by Rolf A.M. Brandt (1960s), P. Temcharoen (1970s) and W.J.M. Maassen (2000s), all of which belonged to the private collection of Jens Hemmen, Wiesbaden, Germany. Relevant items also include types of recently described species coming from the French-Brazilian Marion Dufresne MD55 expedition, and other types deposited by researchers from Brazil and the world. A list of authors and photographs of specimens are also provided.

Aclis macrostoma n. sp. (Figures 1–6) Type material: Holotype, MZSP 77988 [Lt 1.16 mm; Wt 0.80 mm], off the Rio Grande do Norte, Brazil, D- 26, 06º 14 ’04’’S, 34 º 52 ’ 33 ’’W, 510 m, muddy bottom, 26.xi. 2001; 1 paratype, MZSP 77989, off Rio Grande do Norte, Brazil, D-23, 04º 51 ’00’’S, 35 º06’ 46 ’’W, 375 m, muddy bottom, 24.xi. 2001; 2 paratypes, MZSP 77990, off Rio Grande do Norte, Brazil, D-27, 06º 14 ’ 24 ’’S, 34 º 52 ’06’’W, 500 m, muddy bottom, 26.xi. 2001; 1 paratype, LMUFRPE 0 22, off Rio Grande do Norte, Brazil, D-27, 06º 14 ’ 24 ’’S, 34 º 52 ’06’’W, 500 m, muddy bottom, 26.xi. 2001. Type locality: Off the state of Rio Grande do Norte (06º 14 ’04’’S, 34 º 52 ’ 33 ’’W), continental slope of northeast Brazil, at a depth of 510 meters. Diagnosis: Shell low-conical, convex contour, body whorl increasing rapidly in diameter, compared to previous whorls. Penultimate whorl low in relation to diameter. Circular aperture, very expanded peristome, lower part of aperture being drawn out towards the length axis. Description: Shell minute [Lt 1.12 to 1.18 mm], translucent or white, thin, low conical shape, holotype Lt/Wt 1.45. Protoconch globose 1 ½ whorls, smooth, nucleus inflated, slightly inclined (Fig. 6). Teleoconch beginning with emergence of strong orthocline threads, at times with aspect of axial cords, disappearing into subsequent whorls; having 2 ½ post-embryonic whorls, with rounded contours; body whorl increasing rapidly in diameter. Penultimate whorl very low in relation to diameter. Shell entirely polished, with irregular growth scars. Suture well-marked, no ornamentation on margin. Spiral striae microscopic, visible at magnification only in subsutural area (Fig. 2). Base conical, slightly convex. Aperture wide, circular, peristome strongly reflected, expanded forward, lower part of aperture being drawn out towards center of shell. Parietal region weakly reflected with no thickening. Umbilical narrow below reflection of inner lip. Inner lip expanded, umbilical notch narrow (Fig. 5). Etymology: Macros, Gr. = large and Stomatos, Gr.= mouth, in reference to the broad shape of the aperture. Geographic and bathymetric range: Off the state of Rio Grande do Norte (04º 51 ’00’’ – 06º 14 ’04’’S; 34 º 52 ’ 33 ’’ – 35 º06’ 46 ’’W), northeast Brazil, at 375 to 510 m depth. Remarks: The small number of whorls exhibited by the teleoconch of Aclis macrostoma makes any comparison with similar species from the Atlantic difficult, as this species presents a very distinct pattern. The soft parts are unknown, but the holotype demonstrated that shell was fresh, due to its vitreous aspect (Bouchet & Warén 1986: 302). The strongly expanded outer lip, deep umbilicus and circular aperture are not characteristics commonly found in congeners from the North Atlantic, but the group that includes Aclis benedicti (Bartsch, 1947) illustrated in Bartsch (1947: pl. 5, fig. 5) and Aclis attenuans Jeffreys, 1883 illustrated in Bouchet and Warén (1986: figs. 730–732) also presents this dilatation of the peristome. Apparently, the rate of expansion in A. macrostoma is one of the largest ever seen, producing a strongly conical profile that is not common among other species of Aclididae. In Aclis attenuans, the convexity of the smooth whorls, body whorl and chink on the base are similar to A. macrostoma. The planispiral Discaclis canariensis can be matched with Aclis macrostoma regarding size and the similar number of whorls on the protoconch and teleoconch, as well as in the shape of the aperture with a nonthickened outer lip. The former species is broader and has a channeled suture and strong deep basal keel, which are sufficient characters for separating it from A. macrostoma. Aclis gulsonae (Clark, 1850) is similar to Aclis macrostoma regarding the prominence of the outer lip and the nearly straight inner lip, as well as the presence of fine, irregular growth lines. As observed by Jeffreys (1869: 106), the former species is much more slender and truncated (6 to 7 whorls), more cylindrical rather than conical, with a deep suture. Aclis macrostoma and Aclis sarissa present few relevant characters in common. Among these are rounded, glassy and smooth whorls, except for faint growth lines. The last whorl is disproportionately large, well rounded, tumid, and with the suture linear and slightly oblique. In Aclis sarissa, the tip of the apex is prominent. The aperture is oval, with the outer lip slightly narrow, mainly at the union with the body whorl, and the inner lip is thin and sharp. Furthermore, the umbilicus is referred to as funnel-shaped (Watson 1886).

Genus Aclis Lov��n, 1846 Type species: Alvania supranitida Wood, 1842 (= A. minor (Brown, 1827)) by monotypy. The two species described herein fit perfectly into the concept of aclidids as expressed above and are far from being considered pyramidellids or eulimids. Pyramidellidae have the following characteristics: protoconch heterostrophic, aperture pyriform to rhomboid, usually outer lip thin, and one to three collumelar folds (Diaz & Puyana 1994; Pimenta & Absal��o 2004). Eulimidae have shells of variable shape, however, generally narrow, extremely glossy, with very slight whorls and no obvious sculpture, often having a bent spire (Fretter & Graham 1982; War��n 1983)., Published as part of De, Jos�� Carlos N., De, Silvio Felipe B. & Francisco, Jonata De A., 2007, Two new species of Aclis (Mollusca: Gastropoda: Aclididae) from the continental slope of northeast Brazil, pp. 61-68 in Zootaxa 1614 on page 62, DOI: 10.5281/zenodo.179035, {"references":["Wood, S. V. (1842) A catalogue of shells from the Crag. Annals and Magazine of Natural History, 7, 527 - 544.","Brown, T. (1827) Illustrations of the conchology of Great Britain and Ireland. Drawn from nature. W. H. & D. Lizar, Edinburgh. pp. i - v, pis. 1 - 52.","Diaz, M. J. M. & Puyana, H. M. (1994) Moluscos del Caribe Colombiano. Colciencias, Fundacion Natura Colombia, Bogota, 291 pp.","Pimenta, A. D. & Absalao, R. S. (2004) Fifteen new species and ten new records of Turbonilla Risso, 1826 (Gastropoda, Heterobranchia, Pyramidellidae) from Brazil. Bollettino Malacologico, 39, 113 - 140.","Fretter, V. & Graham, A. (1982) The prosobranch molluscs of Britain and Denmark. Part 7. Heterogastropoda (Cerithiopsacea, Triphoracea, Epitoniacea, Eulimacea). Journal of Molluscan Studies, suppl. 11, 363 - 434.","Waren, A. (1983) A generic revision of the family Eulimidae (Gastropoda: Prosobranchia). Journal of Molluscan Studies, suppl. 13, 1 - 96."]}

Aclis macrostoma n. sp. (Figures 1���6) Type material: Holotype, MZSP 77988 [Lt 1.16 mm; Wt 0.80 mm], off the Rio Grande do Norte, Brazil, D- 26, 06�� 14 ���04������S, 34 �� 52 ��� 33 ������W, 510 m, muddy bottom, 26.xi. 2001; 1 paratype, MZSP 77989, off Rio Grande do Norte, Brazil, D-23, 04�� 51 ���00������S, 35 ��06��� 46 ������W, 375 m, muddy bottom, 24.xi. 2001; 2 paratypes, MZSP 77990, off Rio Grande do Norte, Brazil, D-27, 06�� 14 ��� 24 ������S, 34 �� 52 ���06������W, 500 m, muddy bottom, 26.xi. 2001; 1 paratype, LMUFRPE 0 22, off Rio Grande do Norte, Brazil, D-27, 06�� 14 ��� 24 ������S, 34 �� 52 ���06������W, 500 m, muddy bottom, 26.xi. 2001. Type locality: Off the state of Rio Grande do Norte (06�� 14 ���04������S, 34 �� 52 ��� 33 ������W), continental slope of northeast Brazil, at a depth of 510 meters. Diagnosis: Shell low-conical, convex contour, body whorl increasing rapidly in diameter, compared to previous whorls. Penultimate whorl low in relation to diameter. Circular aperture, very expanded peristome, lower part of aperture being drawn out towards the length axis. Description: Shell minute [Lt 1.12 to 1.18 mm], translucent or white, thin, low conical shape, holotype Lt/Wt 1.45. Protoconch globose 1 �� whorls, smooth, nucleus inflated, slightly inclined (Fig. 6). Teleoconch beginning with emergence of strong orthocline threads, at times with aspect of axial cords, disappearing into subsequent whorls; having 2 �� post-embryonic whorls, with rounded contours; body whorl increasing rapidly in diameter. Penultimate whorl very low in relation to diameter. Shell entirely polished, with irregular growth scars. Suture well-marked, no ornamentation on margin. Spiral striae microscopic, visible at magnification only in subsutural area (Fig. 2). Base conical, slightly convex. Aperture wide, circular, peristome strongly reflected, expanded forward, lower part of aperture being drawn out towards center of shell. Parietal region weakly reflected with no thickening. Umbilical narrow below reflection of inner lip. Inner lip expanded, umbilical notch narrow (Fig. 5). Etymology: Macros, Gr. = large and Stomatos, Gr.= mouth, in reference to the broad shape of the aperture. Geographic and bathymetric range: Off the state of Rio Grande do Norte (04�� 51 ���00������ ��� 06�� 14 ���04������S; 34 �� 52 ��� 33 ������ ��� 35 ��06��� 46 ������W), northeast Brazil, at 375 to 510 m depth. Remarks: The small number of whorls exhibited by the teleoconch of Aclis macrostoma makes any comparison with similar species from the Atlantic difficult, as this species presents a very distinct pattern. The soft parts are unknown, but the holotype demonstrated that shell was fresh, due to its vitreous aspect (Bouchet & War��n 1986: 302). The strongly expanded outer lip, deep umbilicus and circular aperture are not characteristics commonly found in congeners from the North Atlantic, but the group that includes Aclis benedicti (Bartsch, 1947) illustrated in Bartsch (1947: pl. 5, fig. 5) and Aclis attenuans Jeffreys, 1883 illustrated in Bouchet and War��n (1986: figs. 730���732) also presents this dilatation of the peristome. Apparently, the rate of expansion in A. macrostoma is one of the largest ever seen, producing a strongly conical profile that is not common among other species of Aclididae. In Aclis attenuans, the convexity of the smooth whorls, body whorl and chink on the base are similar to A. macrostoma. The planispiral Discaclis canariensis can be matched with Aclis macrostoma regarding size and the similar number of whorls on the protoconch and teleoconch, as well as in the shape of the aperture with a nonthickened outer lip. The former species is broader and has a channeled suture and strong deep basal keel, which are sufficient characters for separating it from A. macrostoma. Aclis gulsonae (Clark, 1850) is similar to Aclis macrostoma regarding the prominence of the outer lip and the nearly straight inner lip, as well as the presence of fine, irregular growth lines. As observed by Jeffreys (1869: 106), the former species is much more slender and truncated (6 to 7 whorls), more cylindrical rather than conical, with a deep suture. Aclis macrostoma and Aclis sarissa present few relevant characters in common. Among these are rounded, glassy and smooth whorls, except for faint growth lines. The last whorl is disproportionately large, well rounded, tumid, and with the suture linear and slightly oblique. In Aclis sarissa, the tip of the apex is prominent. The aperture is oval, with the outer lip slightly narrow, mainly at the union with the body whorl, and the inner lip is thin and sharp. Furthermore, the umbilicus is referred to as funnel-shaped (Watson 1886)., Published as part of De, Jos�� Carlos N., De, Silvio Felipe B. & Francisco, Jonata De A., 2007, Two new species of Aclis (Mollusca: Gastropoda: Aclididae) from the continental slope of northeast Brazil, pp. 61-68 in Zootaxa 1614 on pages 62-63, DOI: 10.5281/zenodo.179035, {"references":["Bouchet, P. & Waren, A. (1986) Revision of the Northeast Atlantic bathyal and abyssal Aclididae, Eulimidae, Epitoniidae (Mollusca, Gastropoda). Bollettino Malacologico, suppl. 2, 299 - 576.","Bartsch, P. (1947) A Monograph of the West Atlantic mollusks of the family Aclididae. Smithsoniam Miscellaneous Collection, 106, 1 - 29.","Jeffreys, J. G. (1883) Mediterranean Mollusca, No. 3, and other Invertebrata. Annals and Magazine of Natural History, 5, 393 - 401.","Clark, W. (1850) On the Conovulidae, Tornatelidae and Pyramidellidae. Annals and Magazine of Natural History, 2, 444 - 464.","Jeffreys, J. G. (1869) British Conchology, 5. Van Voors, London, 259 pp.","Watson, R. B. (1886) Report on the Scaphopoda and Gasteropoda collected by H. M. S. \" Challenger \" during the years 1873 - 1876. Reports on the Scientific Results of the Challenger Expedition, Zoology, 42, 1 - 756."]}

Two new species of Aclis Loven, 1846 are described from the continental slope of northeast Brazil. Aclis macrostoma n. sp. is recorded off the state of Rio Grande do Norte at depths ranging from 375 to 510 meters. Aclis watsoni n. sp. was dredged off the state of Sergipe at depths ranging from 365 to 510 meters. There are no similar species along the Brazilian coast. Aclis watsoni is similar to Aclis angulata Smith, 1890, Aclis trilineata Watson, 1897, Aclis supranitida (Wood, 1842) and Aclis ascaris (Turton, 1819) due to the presence of spiral keels and/or indication of a subsutural ramp. Aclis macrostoma is similar to Discaclis canariensis Moolenbeek & Waren, 1987, Aclis attenuans Jeffreys, 1883 and Aclis gulsonae (Clark, 1850) regarding its circular aperture and dilatation of the peristome, with a non-thickened outer lip. The latter two species are much more slender.

Aclis watsoni n. sp. (Figures 7–9) Type material: Holotype, MZSP 77991 [Lt 4.4 mm; Wt 1.4 mm] and 3 paratypes, MZSP 77992, off the state of Sergipe, Brazil, D-6, 10º 41.4 ’00’’S, 36 º 18.7 ’00’’W, 365 m, muddy bottom, 28.x. 2000; 4 paratypes, MZSP 77993, off the state of Sergipe, Brazil, D-7, 11º 35.5 ’00’’S, 37 º 12.3 ’00’’W, 510 m, muddy bottom, 30.x. 2000. Type locality: Off the state of Sergipe (10 º 41.4 ’00’’S, 36 º 18.7 ’00’’W), continental slope of northeast Brazil, at 365 m depth. Diagnosis: Shell elongated, turreted, with strong spiral keels, varying from two to three on body whorl. Aperture elliptic, lower part of aperture being drawn out towards length axis, weakly reflected, forming angles at terminations of spiral keels. Inner lip weakly reflected. Base conical, narrow. Umbilical chink. Description: Shell small [Lt 4.1 to 4.4 mm], white, elongate-turreted shape, polished between spiral keels (Figs. 7, 9), holotype Lt/Wt 3.14. Spire high, with progressively angular contour of post-nuclear, starting at third whorl. Protoconch 1 ½ whorls, globose, slightly inclined nucleus, distinct from remaining whorls, terminating in orthocline axial thread (Fig. 8). Teleoconch with numerous whorls, 6 1 / 3 to 7 1 / 3 whorls in adult specimens, with markedly angular contours due to presence of single median spiral keel to antepenultimate whorl, forming shoulder between second and fifth whorl. Penultimate whorl with presence of second suprasutural keel, evident in last whorl; third higher and weaker keel may be present. Suture well-marked, subsutural region wide, entirely smooth; area below subsutural keel narrower and smooth (Fig. 9). Body whorl following shape of previous whorls. Aperture elliptic, lower part of aperture being drawn out towards center of shell, weakly reflected, forming angles at terminations of spiral keels, with weak posterior sinus. Inner lip weakly reflected on umbilical area. Parietal region fine, no “callus”, columella thick. Base conical, slightly convex, umbilicus in shape of fissure. Etymology: In homage to Mr. R.B. Watson, who first identified species of Brazilian Aclididae. Geographic and bathymetric range: Off the state of Sergipe (10 º 41.4 ’00’’ – 11 º 35.5 ’00’’S; 36 º 18.7 ’00’’ – 37 º 12.3 ’00’’W), northeast Brazil, 365 to 510 m depth. Remarks: Aclis carolinensis Bartsch, 1911 from the North Atlantic may at times develop a keel, as observed by Warén (pers. comm., June 2006, based on types deposited at the Smithsonian Institute). Aclis floridana Bartsch, 1911 presents post-nuclear whorls with a strong sloping shoulder, and featuring a pronounced subsutural carina. However, it is evident that both species have a smaller number of keels that also present a different arrangement to those of A. watsoni. Aclis angulata (St. Helena island) is correlated to Aclis watsoni in its turreted shape, suture depth and the interesting convexity of the whorls, revealing a single strong spiral keel. As observed in Smith (1890: 280, pl. 23, fig. 28), the former species is clearly distinguished by the presence of conspicuous growth threads, a lower spire, a rather inflated body whorl and a protoconch that is much smaller than the first post-nuclear whorls. Aclis minor (Brown, 1827) is similar to A. watsoni regarding the oval to ellipsoidal aperture shape and the weakly reflected, fine, straight parietal region. The former differs from the latter regarding the presence of a broadly umbilicate base, and of an expanded, rounded body whorl with three to five spiral keels. Aclis trilineata Watson, 1897 presents similar morphological features to A. watsoni (see Peñas et al. 2006: 77, figs. 127–128). The contour of the last whorls is correlated in both species, as are the broad subsutural slope, open, rather oblique suture and shallow, small umbilicus. Based on Watson (1897: 255), A. trilineata differs from A. watsoni in having three very strong rounded threads on each post-nuclear whorl (instead of keels), the adapical of which forms a well-marked shoulder, faint close-set microscopic striations and vaguer traces of longitudinal markings. Aclis supranitida (Wood, 1842) and Aclis ascaris (Turton, 1819) are slightly angulated adapically, revealing some indication of a subsutural ramp similar to A. watsoni (see Fretter & Graham 1982: 398, fig. 282 C; 400, fig. 285). The main characteristics that distinguish A. supranitida from A. watsoni are the protoconch with about four whorls, 10–11 swollen whorls, spiral ridges when obvious, three to five on the body whorl and two to four are on more adapical whorls, and growth lines as slight markings. Aclis ascaris and A. watsoni have an umbilicus chink and a shallow anal sinus in common; however, the former is distinguishable by the peripheral bulge and four to five spiral ridges on the last whorl. Aclis watsoni and A. sarissa have conical shells, however, the latter stands out from its congener by the glassy surface, by having nine rounded whorls, and by the posterior region of the aperture that is markedly angulated and effuse on the base.