Pyrgiscus rufus (Philippi, 1836)

Høisaeter, Tore, 2014, The Pyramidellidae (Gastropoda, Heterobranchia) of Norway and adjacent waters. A taxonomic review, Fauna norvegica 34, pp. 7-78 : 65-66

Pyrgiscus rufus (Philippi, 1836)

Figure 108

Melania rufa Philippi, 1836:156 Chemnitzia rufa (Philippi) - Clark 1855 Odostomia rufa (Philippi) - Jeffreys 1848, 1867; Marshall 1900 Turbonilla rufa (Philippi) - Van Aartsen 1981; Rolán Mosquera

1983; Peñas et al. 1996; Peñas & Rolán 1997; Høisaeter

2009; Öztürk & Bakir 2013; CLEMAM 2014 Turbonilla (Chemnitzia) rufa (Philippi) - Malm 1861 Turbonilla (Pyrgostelis) rufa (Philippi) - Kobelt 1903 Turbonilla (Pyrgiscus) rufa (Philippi) - Nordsieck 1972 Pyrgiscus rufa (Philippi) - Schander et al. 2003 Turbonilla (Pyrgiscus) crenata (Brown) - Smith & Heppell 1991 Turbonilla (Pyrgisculus) crenata (Brown) - Winckworth 1932

Type material: Not known. Type locality: Magnisi , eastern Sicily. Material seen: Norway - Skagerrak, 2 shs, Grimstad ,

Aust-Agder (58°20’N, 8°40’E) ; Rogaland, 1 spm, Lysefjorden

(59°N, 5°20’E). Diagnosis: Shell: Pyrgiscus with fairly elongate, slightly

cyrtoconoid shell. Total shell length not exceeding 9 mm. Number of whorls 14 or less. Shell, reddish or fulvous, rarely with coloured band around the periphery, nearly opaque. Sculpture c. 20 slightly opisthocline axial ribs, with wide interspaces. Four to six incised spiral lirae in the interspaces. Whorls evenly rounded, almost flat. Columellar fold visible as a slight thickening of the columella. Protoconch, large for genus, planorboid, only slightly inclined. Soft parts: “Body of a clear pale-azure colour, irregularly aspersed with snow-white flakes; snout (= mentum) extending from the conjoined tentacular membrane to a little beyond the foot, and forming a sort of head-veil; it is long flat and bilobed: tentacles short, broad, very little folded, and diverging; tips rounded: eyes placed on the inner bases of the tentacles: foot large, moderately long, auricled in front, tapering behind to a point when at full stretch, but rounded when at rest.” From Jeffreys (1867), citing Clark (1855). Operculum: Not known.

Biology: Not known. Cabioch (1968) reports Turbonilla crenata as common in fine sediments, 18 m, near Roscoff in the French part of the British Channel. Whether this refers to P. rufus s.s. or P. fulvocinctus is hard to say due to the various interpretation of T. crenata (see below).

Distribution: Never previously reported from Norway. In my material a single specimen, 4.4 mm long from a station in Ryfylke (15 m, soft bottom, 27/8 2007, coll. P. J. Johannessen) and two old and worn shells from Grimstad, Aust-Agder. Outside Norway reported with a query from the Swedish west coast (Schander pers. commn., and Warén in Hansson 1998). The distributional limits are impossible to ascertain because of the confusion with P. fulvocinctus . However, it is reported from the North Sea coast of Scotland by McKay & Smith (1979) (as dead shells). Found chiefly in Devonshire (Clark); Dorsetshire (Hanley); and the S.W. coast of England, in not very deep water ( Forbes & Hanley 1850 -51:276). According to Jeffreys (1867), who regards it as the southern one of two varieties, it has an extensive range southwards from the southern and southwestern coasts of the British Isles, along the Atlantic coasts of France, Spain, Portugal, Madeira and the Canary Isles, and also throughout the Mediterranean and Adriatic. The southern distribution is confirmed by more recent reviews ( Peñas et al. 1996, Peñas & Rolán 1997, Cachia et al. 2001, Öztürk & Bakir 2013)

Remarks: By some authors, (e.g. Smith & Heppell 1991) regarded as a synonym of T. crenata , or by most (following van Aartsen 1981) as conspecific with T. fulvocinctus , but in my opinion a separate species. Van Aartsen (1981:75) states: “ Turbonilla rufa (Philippi, 1836) . Several forms have been described with essentially the same type of spiral sculpture consisting of spirally incised lines. The difference between these forms viz. more or less slender, uniformly coloured or banded and more or less axial ribs, in my opinion are not enough to warrant different species. I therefore regard fulvocincta (Thompson) , crenata (Brown) , fasciata (Req.), spectabilis (Mtrs.), and exigua (Mtrs.) all to be varieties of one and the same species: Turbonilla rufa (Philippi, 1836) .” Several early British malacologists are of another opinion, as is clear from a quotation from Forbes & Hanley (1853:276): “An acquaintance with the specimens of both these shells ( C. rufa and C. fulvocincta ) enables us at length to declare their specific distinctness; on this one point we can accord with the views expressed by Mr. Clark in one of his many papers on the Chemnitzia .” McKay & Smith (1979) record this species from the northern North Sea and the east coast of Scotland. Further down on the page they discuss Turbonilla interrupta (Totten, 1835) [= T. fulvocincta ], for which they state: “Found alive at a number of stations 1922-1924 (Marine Laboratory). There are several 19 th century records and it was obtained dead off Rosehearty in 1977. Many early records may be in error for Turbonilla crenata ”. Fretter et al. (1986) regard fulvocincta as a variety of crenata , but still think there is room for doubt (note, p. 644): “The distinction between crenata and fulvocincta is not always clear - and not always made by systematists - but crenata tends to have fewer costae per whorl than fulvocincta , to have less oblique sutures, and a less regular pattern of colour bands”. The different conclusions add up to a rather confusing picture. Either P. fulvocinctus and P. crenatus are both synonyms of P. rufus , or P. fulvocinctus is a different species from P. crenatus which again is a synonym of P. rufus or the other way around. I provisionally agree with Forbes & Hanley (1853) that P. fulvocinctus and P. rufus are two different species. I accept the arguments of Smith & Heppell (1991) concerning the availability of the names of Brown (1827) for Pyramis crenatus (as well as Eulimella laevis ). However the confusion regarding which species Brown’s P. crenatus refers to (is it a synonym of P. fulvocinctus , or of P. rufus? Both have been suggested, and no types are known) makes it problematic to accept P. crenatus as name for this species. P. rufus was described from a shell from Sicily. Neither P. fulvocinctus nor P. crenatus are mentioned in the literature from the Mediterranean.

Figures

Figure 108. Pyrgiscus rufus. A specimen from Lysefjorden, 59°N, 5°20’E, 15 m, 4.4 mm (Ref 8, 27/07). Figure 109. Pyrgiscus fulvocinctus. Ellingsøyfjorden, Møre og Romsdal, 62°28.7’N, 06°19’E 52-44 m, 7.75 mm (T 70056). Figure 110. Pyrgiscus fulvocinctus. Three orientations of protoconch. Figure 111. Pyrgiscus rufescens. A specimen from Fugløyfjorden, 67°01’N, 13°50.5’E, 70-50 m, 6.95 mm (T 71040). Figure 112. Pyrgiscus rufescens. Protoconch, operculum, head/foot complex. Figure 113. Pyrgiscus rufescens. Two shells illustrating the variability of the species. A shell from Torungen, Hisøy, (Aust-Agder) 58°24’N, 08°47.5’E, 70 m, 3.35 mm (S 66-88) (left), and one from Foldafjorden, 64°40’N, 11°07.5’E, 60-20 m, 3.7 mm (T 69079). Figure 114.Bacteridium cf. carinatum. A specimen from Fensfjorden, 60°45.5’N, 05°14.7’E, 690 m, 1.9 mm without protoconch (E 251A-72) (left), one from Benidorm, Alicante, Spain (1.8 mm), from Peñas et al. (1996), and one from SE of Boa Vista, Cape Verde (1.4 mm) (SEM), from van Aartsen et al. (2000).