Odostomia lukisi, Jeffreys, 1859

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 29-30

‘ Brachystomia’ lukisi Jeffreys, 1859

Figures 34 -37

Odostomia Lukisii Jeffreys, 1859:112 .

Odostomia lukisii Jeffreys - van Aartsen et al. 1984; van Aartsen 1987; Peñas et al. 1996

Odostomia Lukisi Jeffreys - Jeffreys 1867

Odostomia lukisi Jeffreys - Marshall 1899 ; Warén 1980; Høisaeter 1968, 2009

Odostomia (Brachystomia) lukisi Jeffreys - Høisaeter 1986

Odostomia (Brachystomia) lukisii Jeffreys - Winckworth 1932

Brachystomia lukisi (Jeffreys) - Fretter et al. 1986; Graham 1988; Høisaeter 1989

Brachystomia lukisii (Jeffreys) - Smith & Heppell 1991

Ptychostomon lukisi (Jeffreys) - Kobelt 1903

Type material: Twelve syntypes, USNM 132156 ( Warén 1980)

Type locality: Not designated, but Guernsey, Channel Islands is the locality of the syntypes.

Material seen: Norway - Skagerrak , 2 shs; Hordaland, 245 spms.

Diagnosis: Shell: Small (usually less than 2.8 mm), glossy, ivory white. Protoconch intorted, extremely flat (type C) (Figure 36). Growth lines more or less vertical. Soft parts: Tentacles (Figure 35 top) short and wide, apparently without tentacular pads, eyes very close together, mentum characteristically cleft, with diverging ends. Pigmented mantle organ (Figure 35 bottom) in two parts, long and yellow above and short oval, brownish yellow below. Operculum: (Figure 37) with a notch at he columellar side, a ventral thickening in the middle, but no typical ‘anchor’ of the ‘ Odostomia’ - type (see Figure 3 ). Frequently with corroded protoconch and corrosion marks on the whorls ( Figure 34 ).

Biology: According to Fretter et al. (1986) frequently found in association with fairly large assemblages of Pomatoceros , and also with Serpula and Spirorbis . This is also the case for the material from Norway, but the association with Pomatoceros is far less strong than what was observed for O. striolata and O. turrita ( Høisaeter 1989) . Thus it was not found at the Pomatoceros -dominated substrate at the Hillersholmen locality, and the three samples at the Knappensundet locality in which it was found in highest numbers (in one sample even with higher abundance than any other pyramidellid) were all typical Limaria-Modiolus dominated samples.

Distribution: A southern, shallow water species, in Norway only recorded from the Espegrend area except for two shells from Skagerrak and a single older record from Florø (61°36’N) ( Høisaeter 1968). All but two specimens in my material from 11 samples from the locality in Knappensundet (Straume bridge) in Grimstadfjorden (60°19’N) (see Høisaeter 1989). Outside Norway it is reported as occurring sparingly both in the Atlantic and the Mediterranean (van Aartsen 1987). According to Graham (1988) it is among the commonest of intertidal pyramidellids on the west coast of the British Isles and the southern Channel, but is absent from the North Sea. Reported from the western Mediterranean by both van Aartsen et al. (1984) (Algeciras Bay) and Peñas et al. (1996). Van Aartsen et al. (1998) extend the distribution to Mauritania, the Canary Islands, Madeira, and the Azores.

Remarks: Spelling of the specific name varies. Originally ( Jeffreys 1859) spelled it with a double ‘i’ at the end, but later ( Jeffreys, 1867) with a single ‘i’. It is explicitely named after Dr. F.C. Lukis. The choice between the two spellings should be solved based on Article 31.1 of ICZN.The crucial point is the question of whether the name is based on a personal name that is Latin, or from a modern name that is latinized. I interpret Jeffreys’ change of mind as an indication that he did not intend to latinize the name. This is not a Brachystomia s.s., as is clearly seen from the soft parts. It occupies, taxonomically, an isolated position in the Norwegian pyramidellid fauna. The population of this species in Norwegian waters may fluctuate wildly from decennium to decennium, dependent on the amount of larvae brought in with water masses of varying origin and temperature.

Figures

Figure 3. Operculae from four species of odostomine pyramidellids. From left, Brachystomia scalaris, Parthenina interstincta, ‘Brachystomia’ lukisi, Odostomia acuta.

Figure 34. ‘Brachystomia’ lukisi. Two specimens from Knappensundet, Grimstadfjorden (Hordaland), 60°19.3’N, 5°15.8’E, 8 m, 2.7 and 1.75 mm (ZMBN 82536). Figure 35. ‘Brachystomia’ lukisi, head-foot complex and pigmented mantle organ (not to scale). Figure 36. ‘Brachystomia’ lukisi, juvenile. Scale bar = 300 µm. Figure 37. ‘Brachystomia’ lukisi, operculum, two views. Scale bar = 200 µm.