Paralepetopsis variabilis Betters, Cortés & Cordes, 2024, sp. nov.

Paralepetopsis variabilis sp. nov. Fig. 6 Type material examined. Holotype. Costa Rica • whole organism; ethanol-fixed; Original label: “ Paralepetopsis variabilis holotype, 1, whole organism, AD 4987, Costa Rica Margin, Mound 12, 8.92982, - 84.31167, 996 m, from tubeworms. ”; SIO-BIC M 22537. Paratypes: Costa Rica • 9 specimens; same data as for holotype; Original label: “ Paralepetopsis variabilis paratype, 9, whole organisms, AD 4987, Costa Rica Margin, Mound 12, 8.92982, - 84.31167, 996 m, from tubeworms. ”; SIO-BIC M 22538. Costa Rica • 10 specimens; same data as for holotype; Original label: “ Paralepetopsis variabilis paratype, 10, whole organisms, AD 4987, Costa Rica Margin, Mound 12, 8.9298, - 84.31167, 996 m, from tubeworms. ”; MZCR 10675-01 - 10. Type locality. Costa Rica • Costa Rica Margin, Mound 12, 8.92982, - 84.31167; hydrocarbon seep; tubeworms; 996 m; 2 November 2018; AT 42-03 ALVIN Dive 4987 leg. Other material examined. Costa Rica • 11 specimen (s); Costa Rica Margin, Mound 11; 8.9208, - 84.3054; 1,040 m; 25 February 2009; AT 15-44 ALVIN Dive 4504 leg.; Tubeworm, SIO-BIC M 11995 • 3 specimen (s); Costa Rica Margin, Jaco Scar; 9.1172, - 84.8417; 1,866 m; 3 March 2009; AT 15-44 ALVIN Dive 4509 leg.; SIO-BIC M 12037 • 10 specimen (s); Costa Rica Margin, Mound 12; 8.9305, - 84.3123; 1,001 m; 5 March 2009; AT 15-44 ALVIN Dive 4511 leg.; SIO-BIC M 12058 • 25 specimen (s); Costa Rica Margin, Mound 12; 8.93042, - 84.31278; 999 m; 22 May 2017; AT 37-13 ALVIN Dive 4907 leg.; SIO-BIC M 16114 • 9 specimen (s); Costa Rica Margin, Jaco Scar; 9.11538, - 84.83618; 1,859 m; 27 May 2017; AT 37-13 ALVIN Dive 4912 leg.; SIO-BIC M 16126 • 1 specimen (s); Costa Rica Margin, Jaco Scar; 9.11538, - 84.83618; 1,859 m; 27 May 2017; AT 37-13 ALVIN Dive 4912 leg.; SIO-BIC M 16122 • 5 specimen (s); Costa Rica Margin, Jaco Scar; 9.117368, - 84.839661; 1,796 m; 30 May 2017; AT 37-13 ALVIN Dive 4915 leg.; Tubeworm, EC 5815 • 3 specimen (s); Costa Rica Margin, Jaco Scar; 9.117368, - 84.839661; 1,796 m; 30 May 2017; AT 37-13 ALVIN Dive 4915 leg.; Tubeworm, EC 5769 • 7 specimen (s); Costa Rica Margin, Jaco Scar; 9.117368, - 84.839661; 1,796 m; 30 May 2017; AT 37-13 ALVIN Dive 4915 leg.; Tubeworm, EC 5731 • 49 specimen (s); Costa Rica Margin, Jaco Scar; 9.118023533, - 84.84095552; 1,741 m; 31 May 2017; AT 37-13 ALVIN Dive 4916 leg.; Tubeworm, EC 5783 • 11 specimen (s); Costa Rica Margin, Jaco Scar; 9.1193, - 84.84277; 1,854 m; 31 May 2017; AT 37-13 ALVIN Dive 4916 leg.; SIO-BIC M 16170 • 3 specimen (s); Costa Rica Margin, Mound 12; 8.930395, - 84.3124245; 995 m; 1 June 2017; AT 37-13 ALVIN Dive 4917 leg.; Tubeworm, EC 5794 • 3 specimen (s); Costa Rica Margin, Mound 12; 8.9293, - 84.315; 1,000 m; 1 June 2017; AT 37-13 ALVIN Dive 4917 leg.; SIO-BIC M 16161 • 81 specimen (s); Costa Rica Margin, Mound 12; 8.93046775, - 84.31244503; 998 m; 5 June 2017; AT 37-13 ALVIN Dive 4922 leg.; Mussel, EC 5743 • 2 specimen (s); Costa Rica Margin, Quepos Seep; 9.03048, - 84.6202; 1,409 m; 7 June 2017; AT 37-13 ALVIN Dive 4924 leg.; SIO-BIC M 16200 • 8 specimen (s); Costa Rica Margin, Quepos Seep; 9.03048, - 84.6202; 1,409 m; 7 June 2017; AT 37-13 ALVIN Dive 4924 leg.; SIO-BIC M 16182 • 15 specimen (s); Costa Rica Margin, Quepos Seep; 9.03048, - 84.6202; 1,409 m; 7 June 2017; AT 37-13 ALVIN Dive 4924 leg.; SIO-BIC M 16181 • 5 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 7751 • 156 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 7750 • 3 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 7745 • 10 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 7744 • 3 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 10486 • 16 specimen (s); Costa Rica Margin, Jaco Scar; 8.97043, - 84.8429167; 1,724 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Tubeworm, EC 10471 • 63 specimen (s); Costa Rica Margin, Jaco Scar; 9.117433333, - 84.83961667; 1,796 m; 17 10 2018; AT 42-03 ALVIN Dive 4971 leg.; SIO-BIC M 16752 • 3 specimen (s); Costa Rica Margin, Jaco Scar; 9.117433333, - 84.83961667; 1,796 m; 17 October 2018; AT 42-03 ALVIN Dive 4971 leg.; Rock, SIO-BIC M 16733 • 123 specimen (s); Costa Rica Margin, Jaco Scar; 8.97071, - 84.8373; 1,785 m; 18 October 2018; AT 42-03 ALVIN Dive 4972 leg.; Tubeworm, EC 7346 • 6 specimen (s); Costa Rica Margin, Jaco Scar; 8.97071, - 84.8373; 1,785 m; 18 10 2018; AT 42-03 ALVIN Dive 4972 leg.; Tubeworm, EC 7343 • 25 specimen (s); Costa Rica Margin, Jaco Scar; 9.11785, - 84.83728; 1,785 m; 18 October 2018; AT 42-03 ALVIN Dive 4972 leg.; Tubeworm, EC 7340 • 1 specimen (s); Costa Rica Margin, Jaco Scar; 9.11735, - 84.83958333; 1,795 m; 18 October 2018; AT 42-03 ALVIN Dive 4972 leg.; SIO-BIC M 16796 • 37 specimen (s); Costa Rica Margin, Jaco Scar; 9.1178, - 88.839533; 1,783 m; 23 October 2018; AT 42-03 ALVIN Dive 4977 leg.; Mussel, EC 7556 • 1 specimen (s); Costa Rica Margin, Jaco Scar; 9.11775, - 84.83953333; 1,783 m; 23 October 2018; AT 42-03 ALVIN Dive 4977 leg.; SIO-BIC M 16805 • 64 specimen (s); Costa Rica Margin, Mound 12; 8.9308, - 84.31263; 997 m; 24 October 2018; AT 42-03 ALVIN Dive 4978 leg.; Mussel, EC 10473 • 37 specimen (s); Costa Rica Margin, Mound 12; 8.9308, - 84.31263; 997 m; 24 October 2018; AT 42-03 ALVIN Dive 4978 leg.; Mussel, EC 10472 • 425 specimen (s); Costa Rica Margin, Mound 12; 8.9307, - 84.3128; 997 m; 30 October 2018; AT 42-03 ALVIN Dive 4984 leg.; Mussel, EC 8314 • 30 specimen (s); Costa Rica Margin, Mound 12; 8.9307, - 84.3128; 997 m; 30 October 2018; AT 42-03 ALVIN Dive 4984 leg.; Mussel, EC 10477 • 20 specimen (s); Costa Rica Margin, Mound 12; 8.9307, - 84.3128; 997 m; 30 October 2018; AT 42-03 ALVIN Dive 4984 leg.; Mussel, EC 10476 • 6 specimen (s); Costa Rica Margin, Mound 12; 8.9299, - 84.31299; 995 m; 31 October 2018; AT 42-03 ALVIN Dive 4985 leg.; Mussel, EC 10478 • 100 specimen (s); Costa Rica Margin, Mound 12; 8.92983, - 84.31167; 995 m; 2 November 2018; AT 42-03 ALVIN Dive 4987 leg.; Tubeworm, EC 8615 • 1 specimen (s); Costa Rica Margin, Jaco Scar; 9.117783333, - 84.83944667; 1,785 m; 4 November 2018; AT 42-03 ALVIN Dive 4989 leg.; SIO-BIC M 16974 • 2 specimen (s); Costa Rica Margin, Jaco Scar; 9.117783333, - 84.83944667; 1,785 m; 4 November 2018; AT 42-03 ALVIN Dive 4989 leg.; SIO-BIC M 16973 • 2 specimen (s); Costa Rica Margin, Quepos Seep; 9.031816667, - 84.62048333; 1,400 m; 5 November 2018; AT 42-03 ALVIN Dive 4990 leg.; Mussel, SIO-BIC M 16995 • 2 specimen (s); Costa Rica Margin, Quepos Seep; 9.031816667, - 84.62048333; 1,400 m; 5 November 2018; AT 42-03 ALVIN Dive 4990 leg.; Mussel, SIO-BIC M 16994 • 3 specimen (s); Costa Rica Margin, Quepos Seep; 9.031816667, - 84.62048333; 1,400 m; 5 November 2018; AT 42-03 ALVIN Dive 4990 leg.; Mussel, SIO-BIC M 16991 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.1174, - 84.839855; 1,074 m; 7 January 2019; FK 19-0106 SUBASTIAN Dive 214 leg.; Mussel, EC 9348 • 10 specimen (s); Costa Rica Margin, The Thumb; 9.1174, - 84.839855; 1,074 m; 7 January 2019; FK 19-0106 SUBASTIAN Dive 214 leg.; Mussel, EC 9328 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.1174, - 84.839855; 1,074 m; 7 January 2019; FK 19-0106 SUBASTIAN Dive 214 leg.; Mussel, EC 9327 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.05, - 84.4; 1,074 m; 10 January 2019; FK 19-0106 SUBASTIAN Dive 217 leg.; Tubeworm, EC 9480 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.05, - 84.4; 1,074 m; 10 January 2019; FK 19-0106 SUBASTIAN Dive 217 leg.; Mussel, EC 9468 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.05, - 84.4; 1,074 m; 10 January 2019; FK 19-0106 SUBASTIAN Dive 217 leg.; Mussel, EC 9451 • 1 specimen (s); Costa Rica Margin, The Thumb; 9.05, - 84.4; 1,074 m; 10 January 2019; FK 19-0106 SUBASTIAN Dive 217 leg.; Mussel, EC 9434. Diagnosis. Paralepetopsis variabilis sp. nov. may be diagnosed by their ovate, white, semi-translucent shells showing fine, radial growth rings. This species also exhibits two cephalic tentacles which are short (they do not extend past the outer shell margin) and placed low on the head. Soft tissue is whiteish-yellow in color. However, the most reliable way to diagnose Paralepetopsis variabilis sp. nov. is through DNA characterization, as morphology is highly variable within this species and intersects with other known species in the genus. Description. Shell (Fig. 6 A, B): Specimen exhibits uncoiled, patelliform shell. Holotype measures 6.8 mm in length, 4.1 mm in width, and 2.9 mm in maximum height. Shell roundness (width ÷ length) is ~ 0.61. Shell sculpturing and ornamentation lacking but fine radial growth lines are present. Aperture opening is ovate and aperture lip is thin and unornamented. Shell apex is degraded and anteriorly shifted. Anterior and posterior shell slopes are flattened to mildly convex. Shell is very thin, white, and semi-translucent. Soft parts (Fig. 6 C): Soft tissue is white to yellowish in color. Mantle is thick with a mildly crumpled margin. Foot follows the shape of the shell aperture in terms of its roundness. Margin of the foot sole is flat. Pallial tentacles are lacking. Operculum is absent. Two cephalic tentacles are present which are short, thick, and placed low on the head. Eyes are absent. Very reduced oral lappets are present, as well as thickened tissue around the mouth ornamented with very fine frilling. The animal’s head has a slight brownish coloration and a high profile. Radula (Fig. 6 S): Docoglossate radula with formula 2 + 1 + 2 + 1 + 2 + 1 + 2. Rachidian teeth have long shapes, with large triangular cusps at their anterior ends lacking serration. Rachidian teeth are flanked on