Scrupocellaria reptans ( Linnaeus, 1758 )

Vieira, Leandro M. & Spencer, Mary E., 2012, The identity of Sertularia reptans Linnaeus, 1758 (Bryozoa, Candidae), Zootaxa 3563, pp. 26-42 : 31-34

Scrupocellaria reptans ( Linnaeus, 1758)

( Figs 1 , 2 , 6–17 , 24, 26 )

‘ Mufcus coralloides pumilus ramofus’ Ray 1704: 15. [British coast]

‘Creeping coralline’ Ellis 1755: 37, pl. 20, figs b, B. [British coast]

Sertularia reptans Linnaeus, 1758: 815 ; 1767: 1315. [Oceano]

Cellaria reptans: Ellis & Solander 1786: 23 . [British coast]

Cellularia reptans: Couch 1844: 127 , pl. 23, fig. 3. [British coast]

Scrupocellaria reptans: Hincks 1880: 52 (part), pl. 7, fig. 6. [British coast] Scrupocellaria reptans: Prenant & Bobin 1966 (part): fig. 134.vi. [not Mediterranean specimens] Scrupocellaria reptans: Hayward & Ryland 1998: 270 (part). [British coast]

Material examined. Lectotype (chosen here): LSL n. 1248.31.I, no locality, but supposedly British Isles. Paralectotype (chosen here): LSL n. 1248.31.A–H, J–W; LSL n. 1248.32, no locality, but supposedly British Isles. Additional material: NHMUK 1849.2.12.51 (part), Scrupocellaria reptans (Linn.) , on shells (dry), W.P. Cocks collection, Falmouth, Cornwall, U.K.; NHMUK 1884.12.12.9 (part), Scrupocellaria reptans (Linn.) , O. Ridley det., Thanet coast; NHMUK 1915.4.2.13, Scrupocellaria reptans (Linn.) , A.M. Norman collection, George Barlee coll. on algae; NHMUK 1963.3.6.35, Scrupocellaria reptans (Linn.) , C.H. O’Donoghue det., Arisaig, Scotland, British Isles; NHMUK 1995.9.25.26, Scrupocellaria reptans (Linn.) , J.S. Ryland leg. et det., Porth Hellick, Scilly Isles, 11th June 1972; NHMUK 1994.3.4.5–6, Scrupocellaria reptans (Linn.) , P. Hayward det., J. Ellis leg., East side of Dun, St. Kilda, July 1993.

Comparative material. Scrupocellaria ellisi [ Figs 4 , 18–23 , 25, 27 ]: (see next entry). Scrupocellaria sp. 1 [ Fig. 28 ]: NHMUK 2010.12.6.1, Scrupocellaria reptans (part), C.H. O’Donoghue collection, Arisaig, Scotland. Scrupocellaria sp. 2 [ Fig. 29 ]: NHMUK 1963.8.2.16, Scrupocellaria reptans, C.H. O’Donoghue collection, Alexandria, 1937, Stn 7, 66, 17–20 fms. Scrupocellaria sp. 3 [ Fig. 30 ]: NHMUK 1911.10.1.355, Scrupocellaria reptans, A.M. Norman collection, Madeira. Scrupocellaria sp. 4 [ Fig. 31 ]: NHMUK 2010.12.6.21–22, Scrupocellaria reptans (part), C.H. O’Donoghue collection, Gairloch, Scotland.

Redescription. Colony erect, branched, internodes comprising 4–10 zooids. Lateral edge of internode almost straight to slightly curved; chitinous joint passing across gymnocyst and below opesia in both outer zooids (C and D) of bifurcation, and across proximal gymnocyst of inner zooids (F and G). Autozooid subelongate, narrowed proximally, 0.350–0.460 mm long, 0.165–0.205 mm wide, with smooth proximal gymnocyst. Opesia oval, occupying distal half (almost) of zooid, cryptocyst very narrow, inconspicuous. Scutum inserted at midline of inner edge of opesia, branched, occupying most of opesia; slender, flattened, branched 2–3 times, with 6–9 distal stout projections; angled at 100–120°, with first branches about 0.035–0.045 mm wide, and secondary branches about 0.025–0.035 mm. Zooid spines as follows: 1 long distal spine, 3 outer spines, 1–2 inner spines; most proximal outer and inner spines directed frontally; axial zooid with 5 distal spines. One distolateral avicularium sometimes present on each zooid, distolaterally directed and obscured by outer distal spines; rostrum triangular, with slightly serrated lateral edge, mandible triangular. A very large avicularium present on gymnocyst of some zooids, almost aquiline, with a raised tubular base, rostrum serrated laterally, slightly curved and directed forwards; mandible triangular with hooked tip. A basal vibracular chamber often present proximally on basal surface of each zooid, 0.126–0.155 mm long, 0.085–0.115 mm wide, inconspicuous in frontal view; setal groove directed transversely, straight, with smooth seta longer than one zooid length. Single axial vibraculum. A rhizoidal foramen on proximal outer corner of vibracular chamber, absent in axial vibracula. Rhizoids with several close-spaced reverse hooks for most of their length. Ovicell hyperstomial, hemispherical, with 8–13 medium-sized rounded pores; 2 outer and 1–2 inner distal spines in ovicelled zooids.

Distribution. Western Britain.

Figures

FIGURE 1. Linnaeus herbarium sheet no. 1248.31. The colonies were codified by different letters (A – W), with specimen “ I ” (circled) selected as lectotype.

FIGURES 2 – 5. Different shapes of rhizoids found in Scrupocellaria. 2, closely spaced hooks in rhizoids of Scrupocellaria reptans (Linnaeus, 1758) from Great Britain (NHMUK 1963.3.6.35); 3, well-spaced hooks in rhizoids of Scrupocellaria sp. from Red Sea (NHMUK 1928.3.6.177); 4, smooth-surfaced rhizoids of Scrupocellaria ellisi n. sp. from Scotland (NHMUK 1963.3.6.7 a part); 5, annulated surface of rhizoid in Scrupocellaria cyclostoma Busk, 1852 from Australia (NHMUK 1899.6.1.240).

FIGURES 6 – 11. Scrupocellaria reptans (Linnaeus, 1758), type specimens on Linnaeus herbarium sheet n. 1248.31. 6 – 8, lectotype specimen, LSL no. 1248.31. I: 6, frontal view of branches; 7, basal view of branches, with hooked rhizoids; 8, closeup of an axial zooid at a bifurcation, a large frontal avicularium on the right-hand branch. 9 – 11, paralectotypes: 9, close-up of one axial zooid and two ovicelled zooids in paralectotype n. 1248.32. T; 10, close-up of basal surface of paralectotype no. 1248.32. D; 11, close-up of rhizoid with regularly spaced hooks in paralectotype no. 1248.32. H.

FIGURES 12 – 17. SEM of Scrupocellaria reptans (Linnaeus, 1758), NHMUK 1963.3. 6.35. 12 – 15, frontal surface: 12, part of colony; 13, close-up of branch bifurcation, with several frontal avicularia; 14, close-up of axial zooid with frontal avicularium; 15, frontal avicularium in lateral view. 16 – 17, basal surface: 16, part of colony; 17, branches with hooked rhizoids.

FIGURES 24 – 27. Comparison between Scrupocellaria reptans (Linnaeus, 1758) (NHMUK 1963.3.6.35) and Scrupocellaria ellisi n. sp. (NHMUK 1963.3.6.7 a). 24 – 25, Close-up of frontal avicularia, of similar size in young colonies of both species, but with a taller base in S. reptans (24) than found in S. ellisi (25); 26 – 27, frontal surface of zooids, showing the slightly slenderer and more angled scutum in S. reptans (26) than in most proximal zooids of S. ellisi (27); note the differences in avicularium size and the number of distal tines in the scuta of both species.

FIGURES 18 – 23. SEM of Scrupocellaria ellisi n. sp. 18 – 22, NHMUK 1911.10. 1.353, from Shetland, U. K.: 18, part of colony; 19, close-up of branch, with three frontal avicularia in lateral view; 20, bifurcation and ovicelled zooids; 21, close-up of axial zooid with frontal avicularium; 22, basal surface at a bifurcation. 23, colony from Scotland (NHMUK 1963.3.6.7 a), showing smooth-surfaced rhizoids with distal attachment discs.

FIGURES 28 – 31. Four different species found in the NHMUK collection previously misidentified as Scrupocellaria reptans. 28, a specimen from Arisaig, Scotland (NHMUK 2010.12.6.1) with rhizoid hooks but different scutum, frontal avicularia and distal-spine number; 29, a specimen from Alexandria, Egypt (NHMUK 1963.8.2.16), also with different frontal avicularia and distal-spine number; 30, specimen from Madeira (NHMUK 1911.10.1.355), again with differences in ovicells, scuta and shape of frontal avicularia, plus rhizoids with well-spaced hooks; 31, a specimen from Scotland (NHMUK 2010.12.6.22) with robust scuta and frontal avicularia.