Mollusks from Pliocene and Pleistocene seep deposits in Leyte, Philippines Author Kiel, Steffen Author Aguilar, Yolanda M. Author Kase, Tomoki text Acta Palaeontologica Polonica 2020 2020-08-28 65 3 589 627 http://dx.doi.org/10.4202/app.00756.2020 journal article 10.4202/app.00756.2020 1732-2421 12195258 3B7C70AD-CC73-44D5-921E-B1BA0503FC29 Lucinoma tinagoensis sp. nov. Fig. 16 . Zoobank LSID : urn:lsid:zoobank.org:act: 77B57F52-B70F-423A-8914- E0C8C7B5EEB4 Etymology : In reference to the Barangay Tinago, in which the type locality is situated. Fig. 16. The lucinid bivalve Lucinoma tinagoensis sp. nov. from the Pleistocene Cambantug Point seep deposit, Leyte, Philippines. A . Holotype NMP-2164, a large, articulated specimen showing external (A 1 ) and internal (A 2 ) features, and its inflation (A 3 ). B . Paratype NMNS PM 28150, showing fine external sculpture on right valve. Type material : Holotype NMP-2164, an articulated specimen. Paratypes : NMNS PM 28150–28152 (articulated specimens) from the type locality . Type locality : Cambantug Point , Leyte , Philippines . Type horizon : Lower Pleistocene part of the Bata Formation . Material .—The type material only. Dimensions (in mm).—NMP-2164, L = 57.8, H = 57.0, W = 38.9 (articulated). Diagnosis .—Medium-large, well-inflated Lucinoma , outline rounded-pentagonal, umbones pointed, markedly prosogyrate for genus; surface sculpture of numerous sharp to cord-like commarginal ribs, several fine commarginal cords in interspaces; posterodorsal area narrow, posterior sulcus not well developed; lunule broad, short; escutcheon long, broad. Description .—Shell medium-large for genus, greatest width at middle of shell (W/H ratio of single valve = 0.37); anterodorsal margin straight to sinuous,with angulation at transition to somewhat acutely rounded anterior margin; posterodorsal margin evenly convex, with slight angulation at transition to broadly rounded posterior margin; ventral margin evenly convex, without distinct transitions to anterior and posterior margins; shell surface covered by densely spaced, sharp to cord-like commarginal ribs; escutcheon elongate, broad, greatest width in middle; lunule elongate, heart-shaped. Anterior adductor muscle scar moderately narrow, of moderate length for genus, reaching down to ~70% of shell height, detached from pallial by ~30° for c. 2/3 its length. Remarks .—The early Miocene Lucinoma saetheri differs by its smaller and more pointed umbones, narrower escutcheon ( Amano et al. 2018 ). Lucinoma galathea resembles Lucinoma tinagoensis in outline to but is described as “weakly inflated” ( Beu and Maxwell 1990: 281 ) in contrast to the strong inflation of L. tinagoensis . Stratigraphic and geographic range .—Early Pleistocene, Leyte , Philippines .