Seguenzia cervola Dall, 1919

Geiger, Daniel L., 2019, The Family Seguenziidae Verrill, 1884 in the Northeast Pacific, including a comment on excessive numbers of taxonomic data portals, Zoosymposia 13, pp. 61-69 : 64

Seguenzia cervola Dall, 1919

( Figure 2 A–B)

Seguenzia cervola Dall, 1919: 344 . Holotype USNM 209229 . Off North Coronado Island , Baja California, 618–692 fms [= 1130–1265 m].

Seguenzia megaloconcha Rokop, 1972: 15 , fig. 1. Holotype USNM 701260 . SW of Farallon Islands, W of Pioneer Seamount, 3592–3798 m. New synonym.

Description. Shell to 10 mm, globular inflated, suture little impressed; spiral cords decreasing in strength from shoulder to base, one below suture, one on mid-shoulder, more than one dozen from periphery to base; crossed by finest axial lines; umbilicus open, bordered by more or less distinct periumbilical cord, partially covered by umbilical chink, funiculus present; columellar wall thickened, abruptly ending.

Distribution. Oregon (46˚N) to Coronado Islands, Baja Califonia (32˚N). 1100–3800 m.

Remarks. Seguenzia megaloconcha is a small specimen of S. cervola as shown by the identical sculpture on the earlier portion of the teleoconch and the shared umbilical characters.

Figures

FIGURE 2. A–B. Seguenzia cervola Dall, 1919. A. 1130–1266 m, off North Coronado Island, Baja California (USNM 209229, holotype), 4.5 mm. B. 3592–3798 m, SW of Farallon Islands and W of Pioneer Seamount, off San Francisco County, California (USNM 701260, holotype of S. megaloconcha), 9.2 mm. C–D. Seguenzia macleani Geiger, 2017. C. 5100 m, Aleutian Trench at 175° 44' E (LACM 3321), holotype, 8.7 mm. D. 5180 m, abyssal plain W of Oregon, S of Gulf of Alaska (approximately 45° N, 153.8° W) (LACM 3486, paratype), 9.6 mm. E–F. Seguenzia giovia Dall, 1919. E. 874–1097 m, off Santa Catalina Island, Los Angeles County, California (USNM 209228, holotype), 6 mm. F. 3900 m, Tufts Abyssal Plain, W of Lincoln County, Oregon (LACM 2065, holotype of S. quinni), 7.6 mm. G–H. Seguenzia stephanica Dall, 1908. G. 2816 m, Cascadia Abyssal Plain, off Oregon (LACM 70-140.5), 7.1 mm. H. 5100 m, Aleutian Trench, Alaska at 44° N, 175° E (LACM), 5.2 mm.