Conasprella paupera (Harzhauser et. al., 2018)

Descrizione

Diagnosis:

Small Conasprella species with broad, stout shell, low spire, beaded shoulder, and sculpture of well-developed spiral cords separated by broad grooves, with strong, opisthocyrt growth lines visible in grooves. Subsutural flexure shallow, symmetrically curved.

Description:

Shell small, solid, squat, broad biconic, with moderately low spire. Protoconch missing or largely abraded. Teleoconch comprising up to 8.5 whorls with narrow, weakly concave subsutural ramp, periphery placed just above suture, exposing well-defined, rounded to slightly spirally elongate beads at shoulder. Spire whorls with three or four finely granulated spiral cords on subsutural ramp, axial sculpture covering spiral cords and interspaces. Subsutural flexure shallow, symmetrically curved. Last whorl angular at shoulder, slightly convex below, hardly constricted at base, bearing about 20 flattened spiral cords separated by relatively wide interspaces, crossed by densely spaced, opisthocyrt growth lines that are strongest in interspaces, but in some specimens override spiral cords. Siphonal fasciole short, not delimited, weakly recurved. Aperture narrow with parallel margins. Spiral cords slightly lighter coloured than interspaces under UV light, especially beaded cord along periphery.

Remarks:

Martin and Beets identified this taxon as Conus acutangulus (Lamarck, 1810) and Nuttall in Sandal (1996) figured a specimen from the Seria Fm. at Penanjong beach under the same name. Conasprella acutangulus is an extant species well represented also in the SE Asian Miocene. It is much larger and juveniles the size of the Seria Fm. specimens are much narrower with a higher more pointed spire and have spiral grooves instead of relatively wide interspaces.

Conasprella gembacana Martin, 1884 from unnamed Miocene beds at Ngembak in Java is more slender, has a higher straight-sided spire, has larger nodes on the shoulder, has spiral cords with nodes and lacks the spiral furrows.

Distribution:

Only known from the Middle Miocene of Sarawak and the late Miocene of Brunei Darussalam.

Stratum typicum: Seria Fm.

Type locality: Ambug Hill, Brunei Darussalam.

Age: Late Miocene, Tortonian.

Name: Referring to the small size of the species.


Conasprella paupera holotype, RGM.783449 mm. 15,5 x 9,1 Plate 10 figg.12 –14 Tutong 9A, Seria Fm.	Conus acutangulus ⁽²⁾ = Conasprella paupera

Conasprella papera R F5256/001 Plate 10 figg.16 –18	Conasprella paupera paratype, RGM.783411 mm. 14,4 x 9,6 Plate 10 fig. 15 Tutong 8, Seria Fm

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Conus acutangulus 23.8 x 11,9 Chennai ( Tamil Nadu ), India Fresh and very dark specimen. Found by Trawling, 20 - 25 meters deep, February 2018 Tiny chip on the end of the canal [AZRC 308-01]	Conus acutangulus 23,8 x 11,7 mm Chennai ( Tamil Nadu ), India Fresh and very dark specimen. Found by Trawling, 20 - 25 meters deep, February 2018 Tiny chip on the spire end of the canal, [AZRC 308-02]

Conus acutangulus 28,5 x 14,4 mm Chennai ( Tamil Nadu ), India Fresh and very dark specimen. Found by Trawling, 20 - 25 meters deep, February 2018 Tiny chip on the end of the canal [AZRC 308-03]	Conus acutangulus 13,2 x 6,0 mm Hawaii, Honululu Dredged 200 Off Honolulu; 1985 [AZRC 308-04]