Oliveragemmula kieneri

Oliveragemmula kieneri is a species of sea snail, a marine gastropod mollusk in the family Turridae, the turrids.^[1]

Oliveragemmula kieneri
Shell of Oliveragemmula_kieneri
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Subclass:	Caenogastropoda
Order:	Neogastropoda
Superfamily:	Conoidea
Family:	Turridae
Genus:	Oliveragemmula
Species:	O. kieneri
Binomial name
Oliveragemmula kieneri (Doumet, 1840)
Synonyms[1]
Gemmula (Gemmula) kieneri (Doumet), Kilburn, 1983 Gemmula kieneri (Doumet, 1840) Pleurotoma carinata Reeve, 1843 (not Bivona, 1838) Pleurotoma kieneri Doumet, 1840

Its mineralized tissue is made up of calcium carbonate. One may find it in a water depth of 50m (min) to 346m (max).^[2]

Subspecies

• † Gemmula kieneri ryuktjuensis MacNeil, 1960
• † Gemmula kieneri woodwardi (Martin, 1884)

Oliveragemmula kieneri is a species of predatory sea snail, a marine gastropod mollusk belonging to the family Turridae, commonly known as the turrids [1, 2]. It was formally described by Emile Doumet in 1840 as Pleurotoma kieneri [1]. This species is a significant member of the genus Oliveragemmula, a group of deep-water snails primarily found in tropical waters [3, 4].

Description

The shell of Oliveragemmula kieneri is robust and fusiform (spindle-shaped), with its length varying considerably between 26.2 mm and 73 mm [1, 5]. This range indicates that it can grow to a moderately large size for a turrid snail.

Key features of the shell, also common to the genus Gemmula to which it originally belonged, often include:

• High Spire: The shell typically has a tall, pointed spire [4].
• Whorls: It possesses multiple whorls, often numbering around 10 or more [4].
• Sculpture: The surface ornamentation is characteristic of the genus, featuring strong spiral cords and axial ribs or nodules. A prominent subsutural fold, often composed of two closely spaced gemmate (bead-like) cords, is a common trait. Below this, there are typically two major cords between the peripheral carina (a keel-like ridge) and the lower suture, with finer threads in the interspaces [4, 6]. The sculpture often creates a nodular or beaded appearance, particularly on the shoulder of the whorls [5].
• Anal Sinus: A distinctive feature of turrids is the anal sinus, a deep notch or slit on the outer lip of the aperture, located near the suture. In Gemmula, this sinus is typically well-defined and often U-shaped [4].
• Siphonal Canal: The shell possesses a relatively long, narrow anterior (siphonal) canal [4].
• Coloration: While descriptions of specific color patterns are not always detailed, Gemmula species can exhibit variations in shades of white, cream, and light brown, sometimes with subtle banding [4].

A.W.B. Powell (1964), a significant authority on Turridae, noted the close morphological similarity between O. kieneri and Oliveragemmula speciosa, another well-known species in the genus [1]. The exact nuances distinguishing them often require careful examination of sculptural details and anatomical features.

Distribution

Oliveragemmula kieneri is a widespread marine species found across the Indo-Pacific biogeographic region [1]. Its recorded distribution includes:

• Papua New Guinea [1]
• East China Sea and South China Sea, including the Nansha Islands [1, 4]
• Japan (off Choshi, in the Japan Sea, and East China Sea) [1, 5]
• Philippines (including Bohol) [1, 3]
• Queensland, Australia [1]

This extensive distribution highlights its adaptation to the warm, tropical waters of the Indo-Pacific.

Habitat and Ecology

Oliveragemmula kieneri is a benthic species, meaning it lives on or near the seabed [7]. It is typically found in deeper tropical waters, with recorded depths ranging from 20 meters to 346 meters [1, 5, 7]. Studies on Gemmula species in the Philippines have collected specimens from depths between 50 and 100 meters, often as by-catch from commercial fish trawlers [3]. Other collection methods, such as tangle nets, have yielded specimens from even greater depths, up to 600 meters for the genus overall, indicating a preference for sublittoral to bathyal zones [4].

The preferred substrate for O. kieneri is typically sand or muddy sand [5]. Like other members of the superfamily Conoidea, these species are predatory marine snails. Research suggests that species within the genus Gemmula are specialized worm-hunters, primarily preying on Terebellidae (a family of marine segmented worms) [3]. Their feeding behavior and detailed ecology are still being studied, partly due to the inaccessibility of their deep-water habitats and their often nocturnal and burrowing habits [3].

Taxonomy and Synonyms

The original binomial name was Pleurotoma kieneri Doumet, 1840 [1].

Synonyms of Oliveragemmula kieneri include [1]:

• Pleurotoma carinata Reeve, 1843 (not Bivona, 1838)
• Pleurotoma kieneri Doumet, 1840 (original combination)

It is important to note that a recent taxonomic revision has proposed a new genus, Oliveragemmula Kantor, Bouchet, Fedosov, Puillandre & Zaharias, 2024, and Gemmula kieneri has been assigned to this new genus as Oliveragemmula kieneri (Doumet, 1840). This reclassification reflects ongoing efforts to refine the systematics of the complex Turridae family based on comprehensive morphological and molecular data [2]. However, the original Gemmula kieneri name is still widely recognized in many sources.