Serpula concharum Langerhans, 1880

Ben-Eliahu, M. Nechama & Ten Hove, Harry A., 2011, Serpulidae (Annelida: Polychaeta) from the Suez Canal- From a Lessepsian Migration Perspective (a Monograph) 2848, Zootaxa 2848 (1), pp. 1-147 : 72

Serpula concharum Langerhans, 1880

Type locality. Atlantic Ocean, Madeira. Not present in the Suez Canal; however, for literature records under this name from the Suez Canal, see Hydroides elegans , Hydroides spp. and Serpula hartmanae .

Remarks. The name has frequently been used for the juvenile stage of Hydroides that lacks an upper verticil (ten Hove & Ben-Eliahu 2005).

As concerns Serpula concharum s. str., with its more than 150 literature records, this Atlantic- Mediterranean species should be a well-known taxon. Its tube is rounded trapezoidal in cross-section, with five more or less similar longitudinal ridges (e.g., Langerhans 1880: 118–119; Bianchi 1981: 47–49, fig. 14). However, according to Zibrowius (1968: 98–100), the tube may have 3–5 ridges, and intermediate forms exist. Fauvel (1927: 352–353, fig. 121) and Rioja (1931: 404–406, pl. 128) explicitly mention 5 ridges in the text, but figure only three. Material collected by us along the Israeli coast up to depths of 20 meters only showed 3-ridge tubes, with a rather square trapezoidal cross-section, as opposed to the material from deeper localities with 5 ridges and more circular cross-sections. Therefore, Ben-Eliahu & ten Hove (1992: 41) attributed the shallow water population from Israel to Serpula cf. concharum ; subsequently Ben-Eliahu & Fiege (1996: 6) used S. concharum “ type B” to indicate this form with 3 longitudinal ridges while Bianchi & Morri (2000: 260, fig. 2) used Serpula sp. Probably S. concharum sensu auct. from the Atlantic- Mediterranean is a complex of a complex of—at least—two species and much work remains to be done on the variability of taxonomic characters, particularly in the shallow water material. The revision of the taxon should be based both on the available morphological specimens and on genetic studies. Records under this name from outside the Atlantic-Mediterranean probably belong to other taxa (see Remarks in section of Serpula hartmanae , below). A recent report of Serpula concharum from shallow water off Alexandria in Egypt by El-Rashidy et al. (2009) may well be the same taxon as the material present in shallow depth from the coast of Israel.