Asperdaphne (Asperdaphne)

Asperdaphne brenchleyi, copyright Des Beechey.

Belongs within: Raphitomidae.

Asperdaphne, I don’t know who you are anymore
Published 2 October 2012
A true Asperdaphne: the type species A. versivestita, photographed by Des Beechey.

The subject of today’s post has been going through something of an identity crisis recently. Asperdaphne was listed by Powell (1966) as a genus of small conoid gastropods found in Australia, New Zealand and the Pacific coast of Asia, with a fusiform shell and coarse clathrate (lattice-like) ornamentation. This remains the sense in which it has been most commonly recognised. However, in a paper published just last year, Beu (2011) revealed that this picture of Asperdaphne was a fraud. The majority of species assigned to Asperdaphne by Powell (1966) were not members of the same genus as the type, A. versivestita. Instead, they belonged to another genus, Pleurotomella, the type species of which Powell had not been familiar with. Meanwhile, A. versivestita was more appropriately placed with what Powell had called Tritonoturris, an Indo-Pacific genus of larger conoids with a more ovate shell shape. As Asperdaphne was an older genus name than Tritonoturris, this meant that what had been Tritonoturris was now Asperdaphne, while what had been Asperdaphne was now Pleurotomella. The identity of the two east Asian species assigned to Asperdaphne by Powell (1966) was not discussed by Beu (2011).

Not an Asperdaphne: Pleurotomella hayesiana, also photographed by Des Beechey.

We have encountered this paper of Beu’s before, when I cited it in the post on another conoid genus, Kuroshioturris. As with that genus, the recognition of Asperdaphne had been confused by differences in protoconch morphology related to larval nutrition. Species assigned to ‘Tritonoturris‘ had a tall conical protoconch, indicating a planktotrophic (feeding on plankton) lifestyle as a larva, while Asperdaphne versivestita has a blunt-tipped paucispiral protoconch, indicating that its larvae are lecithotrophic (‘fed’ by energy reserves in the yolk).

Diagram of the foregut of ‘Tritonoturris’ subrissoides, from Fedosov (2008).

Slightly more mysterious are Asperdaphne‘s feeding habits as adults. Foregut structure has been investigated for one presumed Asperdaphne species, under the name Tritonoturris subrissoides (Fedosov 2008). T. subrissoides is one of a number of members of the family Raphitomidae to show a reduction in foregut structures, and has lost the radula and venom gland of most conoids. Instead, it has a large introvert (extendable proboscis) that probably functions in prey capture. However, the roof of the introvert has a large and elongate outgrowth, unlike any found to date in any other conoid, with a well differentiated muscle system indicating that it is capable of complex movement. Presumably, this outgrowth functions somehow in prey capture (perhaps as a grasping ‘finger’?) but its exact purpose remains unknown.

Systematics of Asperdaphne (Asperdaphne)
<==Asperdaphne Hedley 1922 (Asperdaphne)P66
    |--*A. (A.) versivestita (Hedley 1912) [=Daphnella versivestita, *Scabrella versivestita]P66
    |--A. (A.) aculeata (Webster 1906) [=Daphnella aculeata]P66
    |--A. (A.) amplecta Hedley 1922P66 [=Fusidaphne amplectaL54; incl. A. amabilis Brazier 1876 non Hinds 1844C47]
    |--A. (A.) balcombensis Powell 1944P66
    |--A. (A.) bastowi (Gatliff & Gabriel 1908) [=Daphnella bastowi]P66
    |--A. (A.) bela Hedley 1922 [=Bela tasmanica May 1915 non Daphnella tasmanica Tenison-Woods 1877]P66
    |--A. (A.) bitorquata (Sowerby 1896)P66 [=Daphnella bitorquataP66, A. tasmanica var. bitorquataH22]
    |--A. (A.) brenchleyi (Angas 1877)P66 [=Clathurella brenchleyiP66, Daphnella brenchleyiH22]
    |--A. (A.) capricornea Hedley 1922P66
    |--A. (A.) compacta Hedley 1922P66
    |--A. (A.) contigua Powell 1944P66
    |--A. (A.) desalesii (Tenison-Woods 1877)P66 (see below for synonymy)
    |--A. (A.) esperanza (May 1911) [=Hemipleurotoma esperanza]P66
    |--A. (A.) expeditionis Dell 1956P66
    |--A. (A.) hayesiana (Angas 1871) [=Clathurella hayesiana]P66
    |--A. (A.) laceyi (Sowerby 1888) [=Pleurotoma (Bela) laceyi]P66
    |--A. (A.) moretonica (Smith 1882)P66 [=Pleurotoma (Defrancia) moretonicaP66, Clathurella moretonicaH09]
    |--A. (A.) peradmirabilis (Smith 1879) [=Drillia peradmirabilis]P66
    |--A. (A.) perplexa (Verco 1909) [=Daphnella perplexa]P66
    |--A. (A.) rugosa Laseron 1954P66
    |--A. (A.) sculptilis (Angas 1871)P66 (see below for synonymy)
    |--A. (A.) sepulta Laseron 1954P66
    |--A. (A.) tasmanica (Tenison-Woods 1877) [=Daphnella tasmanica]P66
    |--A. (A.) trimaculata Cotton 1947P66
    |--A. (A.) ula (Watson 1881)P66 [=Pleurotoma (Drillia) ulaP66, P. (Bela) ulaD56]
    |--A. (A.) vercoi (Sowerby 1896)P66 (see below for synonymy)
    |--A. (A.) vestalis (Hedley 1903)P66 [=Daphnella vestalisP66, Hemipleurotoma vestalisH22]
    `--A. (A.) walcotae (Sowerby 1893)P66 [=Drillia walcotaeP66, Clathurella walcotaeH22]

Asperdaphne (Asperdaphne) desalesii (Tenison-Woods 1877)P66 [=Mangelia desalesiiP66, Clathurella desalesiH22, Scabrella desalesiiH22; incl. Clathurella sculptior Tenison-Woods 1879P66, C. sexdentata Pritchard & Gatliff 1900P66]

Asperdaphne (Asperdaphne) sculptilis (Angas 1871)P66 [=Clathurella sculptilisP66, Daphnella sculptilisH22; incl. D. angasi Hedley 1903P66]

Asperdaphne (Asperdaphne) vercoi (Sowerby 1896)P66 [=Daphnella vercoiP66; incl. A. brenchleyi Tate 1893 non Clathurella brenchleyi Angas 1877C47]

*Type species of generic name indicated

References

Beu, A. G. 2011. Marine Mollusca of isotope stages of the last 2 million years in New Zealand. Part 4. Gastropoda (Ptenoglossa, Neogastropoda, Heterobranchia). Journal of the Royal Society of New Zealand 41 (1): 1–153.

[C47] Cotton, B. C. 1947. Australian Recent and Tertiary Turridae. Field Naturalists’ Section of the Royal Society of South Australia Conchology Club, Publication 4: 1–34.

[D56] Dell, R. K. 1956. The archibenthal Mollusca of New Zealand. Dominion Museum Bulletin 18: 1–235.

Fedosov, A. E. 2008. Reduction of the alimentary system structures in predatory gastropods of the superfamily Conoidea (Gastropoda: Neogastropoda). Doklady Biological Sciences 419: 136–138.

[H09] Hedley, C. 1909. The Marine Fauna of Queensland: Address by the President of Section D. Australasian Association for the Advancement of Science: Brisbane.

[H22] Hedley, C. 1922. A revision of the Australian Turridae. Records of the Australian Museum 13 (6): 213–359, pls 42–56.

[L54] Laseron, C. F. 1954. Revision of the New South Wales Turridae (Mollusca). Royal Zoological Society of New South Wales: Sydney.

[P66] Powell, A. W. B. 1966. The molluscan families Speightiidae and Turridae: an evaluation of the valid taxa, both Recent and fossil, with lists of characteristic species. Bulletin of the Auckland Institute and Museum 5: 1–184, pls 1–23.

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