Weltneria spinosa Berndt, 1907

Botha, Thomas P. A. & Griffiths, Charles L., 2021, South African Acrothoracica (Crustacea: Cirripedia), Zootaxa 4949 (1), pp. 45-78 : 56-57

Weltneria spinosa Berndt, 1907

Figs 7–9

Weltneria spinosa Berndt, 1907: 289 .— Tomlinson 1969: 32–36, fig. 1.— Tomlinson 1987: 65, fig. 2.— Kolbasov & Høeg 2007: 129, fig. 3 (A), fig. 5 (A, F), fig. 7 (A), fig. 8 (C), 1 fig. 9 (E), fig. 11 (E).— Kolbasov 2009: 284 (in Russian), fig. 2 (a), fig. 5 (ж), fig. 14 (е, ж), fig. 25 (г), fig. 28 (б), fig. 37 (a), fig. 39 (e), fig. 49 (a), fig. 51 (a), fig. 53 (a, e, ж, З, u), fig. 55 (в), fig. 56 (б, u), fig. 58 (б), fig. 60 (б), fig. 85.

Deposited material. SAMC-A091113 , False Bay , Western Cape, January and February 2017, 34 specimens from 6 Turbo sarmaticus shells (5 not deposited, used for genetic analyses) . SAMC-A091114 , False Bay , Western Cape, January and February 2017, 376 specimens from 8 Turbo sarmaticus shells (10 not deposited, used for dissections and light microscopy) . SAMC-A091115 , Chintsa West , Eastern Cape, April 2017, 25 specimens from 4 Turbo sarmaticus shells (2 not deposited, used for SEM) . SAMC-A091116 , Gonubie , Eastern Cape, April 2017, 105 specimens from 5 Turbo sarmaticus shells . SAMC-A091117 , Gonubie , Eastern Cape, 27 April 2017, 12 specimens from Haliotis midae shell . SAMC-A091118 , Gonubie , Eastern Cape, 27 April 2017, 223 specimens from Haliotis midae shell (3 not deposited, used for genetic analyses) . SAMC-A091119 , Melkbosstrand , Western Cape, 28 February 2017, 13 specimens from Haliotis midae shell . SAMC-A091120 , Gonubie , Eastern Cape, 27 April 2017, 30 specimens from Ranella gemmifera shell . SAMC-A091121 , Gonubie , Eastern Cape, 27 April 2017, 6 specimens from Ranella gemmifera shell . SAMC-A091122 , False Bay , Western Cape, 19 February 2017, 1 specimen from Argobuccinum pustulosum shell (2 not deposited, used for SEM) . SAMC-A091123 , False Bay , Western Cape, 17 February 2017, 9 specimens from Argobuccinum pustulosum shell . SAMC-A091124 , False Bay , Western Cape, 14 March 2017, 11 specimens from Argobuccinum pustulosum shell . SAMC-A091125 , False Bay , Western Cape, 14 March 2017, 3 specimens from Argobuccinum pustulosum shell . SAMC-A091126 , Melkbosstrand , Western Cape, 28 February 2017, 5 specimens from Turbo cidaris shell . SAMC-A091127 , Melkbosstrand , Western Cape, February 2017, 30 specimens from 2 Turbo cidaris shells . SAMC-A091128 , Chintsa West , Eastern Cape, 26 April 2017, 3 specimens from Dinoplax gigas . SAMC-A091129 , False Bay , Western Cape, 15 March 2017, 2 specimens from Burnupena cincta shell . SAMC-A091130 , East London surrounds (Gonubie, Chintsa West ), Eastern Cape, April 2017, 8 specimens from 2 Mancinella capensis shells (2 not deposited, used for genetic analyses) . SAMC-A091131 , Gonubie , Eastern Cape, 27 April 2017, 51 specimens from Mancinella capensis shell . SAMC-A091132 , Summerstrand , Eastern Cape, 4 July 2017, 6 specimens from Mancinella capensis shell . SAMC-A091133 , L’Agulhas , Western Cape, 15 June 2010, 1 specimen in Heydrichia woelkerlingii . SAMC-A091134 , Summerstrand, Algoa Bay , Eastern Cape, 4 July 2017, 30 specimens in Lithophyllum sp . SAMC-A091135 , Morgan Bay , Eastern Cape, 13 July 2010, 12 specimens from Lithophyllum neoatalayense Masaki . SAMC-A091136 , False Bay , Western Cape, 4 August 2016, 4 specimens from Scutellastra tabularis shell .

Diagnosis. Females with pair of large hooks forming posterior processes of operculum, inner and outer margins of operculum with simple or bifid teeth. Also characterised by presence of pair of weak and irregular lateral bars.

Description. Female, body oval-shaped (fig. 7B; 9A). Length 2.1–4.7 mm (mean = 2.98 mm), width 1.05–2.85 mm (mean = 1.69 mm). Opercular bars on average 0.87 mm long, with pair of large, curved posterior processes at top of operculum armed with several simple teeth and setae (fig. 8B, D; 9B). Both inner and outer margins of operculum lined with bifid or simple teeth and setae (fig. 8C, D, E). Rostral end of opercular bar with simple spines and setae (fig. 8E). Lateral surface of operculum lined with several teeth, setae and large multifid scales (fig. 8B, F). Comb collar consisting of long feather-like projections (fig. 8A). Developed orificial knob absent. Feeble lateral bars present running down mantle near operculum (fig. 9A). Row of small, mostly bifid teeth running down ventral surface on mantle. Females bright red when fresh, cirri also bright red (fig. 7A, C). Aperture resembles typed apostrophe, with one end having more pointed tapered slit (fig. 7C).

Five pairs of terminal cirri, with pair of two-segmented caudal appendages (fig. 9C, D), two conical processes present (fig. 9C). Mouth cirri with four-segmented posterior ramus shorter than five-segmented anterior ramus, both with long setae (fig. 9G). Labrum saddle-shaped, mandibular palp trapezoid, with dense setae (fig. 9H). Mandible with three teeth, excluding inferior angle (fig. 9E), first tooth separated from second and third by large notch, inferior angle with several small spines and setae. Maxillule with single notch in middle of outer margin, two long cuspidate setae below notch, with three short, sharp setae above notch (fig. 9F). Male much smaller than female, average of 0.66 x 0.32 mm, with up to four on a single female.

Hosts. The type-host is Haliotis midae . Also previously known from Argobuccinum pustulosum and Turbo sarmaticus ( Tomlinson, 1969) . New hosts in the Western Cape include Burnupena cincta , Dinoplax gigas , Scutellastra tabularis and Turbo cidaris . Collected in the Eastern Cape from two new hosts, Ranella gemmifera and Mancinella capensis , as well as from T. sarmaticus and H. midae . Also found inhabiting coralline red algae ( Botha, Griffiths & Maneveldt, 2020) in the Eastern Cape in a rhodolith (Lithophyllum sp.), a discoid species, Lithophyllum neoatalayense, also from Heydrichia woelkerlingii in the Western Cape.

Distribution. Type locality Hermanus (3425’1.62”S, 1914’55.46”E) in the Western Cape. Ranges from Melkbosstrand (3344’08.1”S, 1826’15.2”E) to Qolorha (3250’08.0”S, 2807’09.5”E). Endemic to Western and Eastern Cape provinces. All specimens were collected in water <5 m deep.

Remarks: Weltneria spinosa Berndt, 1907 is the type species of the genus and is the most common acrothoracican in South Africa, with up to 235 individuals found in a single Haliotis midae shell. Often found in the same host with Australophialus turbonis in the Western Cape and Australophialus utinomii and Kochlorine bocqueti in the Eastern Cape. In the Western Cape, empty burrows of this barnacle are often occupied by the unique amphipod Ampelisca excavata , which appears to be restricted to, and anatomically adapted, to live in this specialised niche ( Gray & Barnard, 1970). We recorded this amphipod in W. spinosa holes on both T. sarmaticus and, in great abundance, on the coralline algae H. woelkerlingii .

Figures

FIGURE 7. Weltneria spinosa collected from Turbo sarmaticus from False Bay, female. A—Female feeding using cirri; B— Lateral view of whole specimen; C—Natural colouration showing opercular bars with posterior processes.Abbreviations: ak— attachment knob, mt—mantle, ob—opercular bar, obp—posterior process of opercular bar.

FIGURE 8. Weltneria spinosa from Argobuccinum pustulosum collected in False Bay. Scanning electron microscopy of external morphology of opercular area, female. A—Comb collar; B—Upper area of opercular bar showing posterior process; C—Three rows of bifid and simple teeth on opercular bar with setae; D—Opercular area; E—Anterior end of opercular bar with simple teeth and setae; F—Multifid scales. Abbreviations: cc—comb collar, ob—opercular bar, obp—posterior process of opercular bar.

FIGURE 9. Weltneria spinosa from Turbo sarmaticus in False Bay. Light microscopy of external mantle and structures of body proper, female.A—Lateral view of whole specimen; B—Lateral view of opercular area; C—Terminal cirri; D—Caudal appendage; E—Mandible; F—Maxillule; G—Mouth cirri; H—Labrum and mandibular palp. Abbreviations: ca—caudal appendage, cp—conical process, la—labrum; mdp—mandibular palp.