Siphonaria lateralis Gould, 1846

Jenkins, Bruce & Köhler, Frank, 2024, Hidden in plain sight: Systematic review of Indo-West Pacific Siphonariidae uncovers extensive cryptic diversity based on comparative morphology and mitochondrial phylogenetics (Mollusca, Gastropoda), Megataxa 13 (1), pp. 1-217 : 76-79

Siphonaria lateralis Gould, 1846

( Figs 29H–L, P, S–T , 30E–G )

Siphonaria lateralis Gould 1846: 11 (type locality: Burnt Island, Orange Harbor [Tierra del Fuego, Argentina]).— Gould 1848: 153; 1852: 363; 1856: 12, fig. 462 a,b; Hanley 1858b: 152; H. Adams & A. Adams 1855 (in 1853–58): 271; 1863: 271; Rochebrune & Mabille 1888: H.29; Paetel 1889: 428; Lamy 1910: 202; Iredale 1915: 478; Lamy 1915: 74; 1931: 581; Powell 1937: 86; Gaillard 1954: 525; Powell 1955: 122; 1960: 163; Simpson 1976: 11; White & Dayrat 2012: 64; Güller et al. 2015: 87, fig. 6A, E, I; González-Wevar et al. 2018: 3.

Siphonaria redimiculum — Hutton 1880: 36; 1883: 143; Hedley 1916: 61; Filhol 1880: 552; Melvill & Standen 1907: 142; Dell, 1964: 290 (not S. redimiculum Reeve, 1856 ).

Siphonaria (Liriola) lateralis — Dall 1870: 32; Suter 1909a: 33; 1913: 601; Tomlin 1948: 229; Christiaens 1980a: 81.

Kerguelenia redimiculum — Suter 1909a: 37; Iredale 1915: 478; Hedley 1916a: 61; Powell 1937: 86 (not S. redimiculum Reeve, 1856 ).

Siphonaria tristensis — Suter 1904: 68 (not Siphonaria tristensis Sowerby I, 1823 ).

Kerguelenia redemiculum Lamy 1910: 202 (invalid: incorrect subsequent spelling of redimiculum ; not S. redimiculum Reeve, 1856 ).— Powell 1937: 86; 1939: 237.

Kerguelenia innominata Iredale 1915: 478 (type locality: subantarctic Islands of New Zealand).— Hedley 1916a: 62; Odhner 1924: 55; Finlay 1927: 442; Powell 1937: 86; 1939: 237; 1955: 122; Hubendick 1945: 66; White & Dayrat 2012: 64.

Kerguelenia lateralis — Hedley 1916a: 62.

Kerguelenia macquariensis Powell 1939: 328 , pl. 49, figs 9–10 (type locality: Macquarie Island [ Australia]).— Hubendick 1945: 66; Powell 1946: 91; Dell 1964: 290; White & Dayrat 2012: 65.

Siphonaria (Kerguelenia) lateralis — Hubendick 1945: 66, fig. 15, 59; 1946: 26, pl. 1, figs 22–25; Marcus & Marcus 1960: 114.

Kerguelenella lateralis — Carcelles 1953: 206; Powell 1957a: 114, pl. 31, figs 9, 10; 1957b: 137; Dell 1964: 290; 1971: 215; Gaillard 1971: 298; Arnaud 1974: 452; Simpson 1977: 126, 132, fig. 7; Powell 1979: 279, pl. 54, figs 18, 19; Branch et al. 1991: 55; Forcelli 2000: 132, fig. 423; Griffiths & Waller 2016: 1147.

Kerguelenella redimiculum — Powell 1955: 122.

Kerguelenella innominata — Boreham 1959: 71; Powell 1957a, 114; 1979: 293, pl. 54, figs 16–17; Raven & Bracegirdle 2010: 46.

Siphonaria (Pugillaria) lateralis — Morrison 1963: 8.

Siphonaria magellanica — Dell 1964: 290 (not S. magellanica Philippi, 1857 ).

Kerguelenella lateralis macquariensis — Powell 1946: 91, figs 9– 10; 1955: 122; 1957b: 140; 1960: 163.

Siphonaria lateralis macqueriensis — Galindo 1977: 416 (incorrect subsequent spelling of macquariensis ).

Pugillaria lateralis — Trew 1983: 3.

Siphonaria (Kerguelenella) lateralis — Chambers & McQuaid 1994b: 418; Chambers et al. 1998: 51.

Siphonaria ‘ lateralis group, unit 6’ — Dayrat et al. 2014: 266, fig. 3F–G.

Material examined. Type material. Holotype of Siphonaria lateralis Gould, 1846 from ‘ Burnt Island , Orange Harbor’ [Tierra del Fuego, Argentina]; coll. Carpenter ( USNM 5853 , figured in Güller et al. 2015: 88, figs. 6A, E, I).

Eight syntypes of S. macgillivrayi Reeve, 1856 from Island of St. Paul’s [Indian Ocean] ( NHMUK 1981003 ) .

Lectotype of S. redimiculum Reeve, 1856 , designated by Güller et al. (2015: 92, fig. 8O, T), without type locality ( NHMUK 1981004/1 ). Four paralectotypes of S. redimiculum , same data as lectotype ( NHMUK 1981004/2-5 ; figured by Güller et al. 2015: fig. 8P–S).

Lectotype of Kerguelenella innominata ( Iredale, 1915) , designated by Boreham (1959: 71), from Disappointment Island, Auckland Islands [ New Zealand] ( GNS TM1203 , Fig. 29H ); two paralectotypes, from Auckland Is; coll. Capt Bollons ( AM C.43852 ).

Holotype of Kerguelenia stewartiana Powell, 1939 from Akers Point , Stewart Island, NZ; coll. R.H. Harrison ( AWMM MA. 70377 ); paratypes of K. stewartiana ; same data as holotype, one ( MA 71589 ), two ( GNS TM1969 , TM 1970 ), 10 ( AM C.585966 ); one from Akers Island, Stewart Island , New Zealand; coll. R.H. Harrison ( USNM 880297 ).

Holotype of Kerguelenia macquariensis Powell, 1939: 238 from Macquarie Island, Australia; coll. H.J. Finlay ( AWMM MA. 70376 ; Fig. 29I ). Two paratypes of K. macquariensis , same data as holotype ( GNS TM1969– 1970 ).

Holotype of Kerguelenella flemingi Powell, 1955 from Bay S of Crozier Pt , Auckland Island, NZ ( GNS TM1204 ). Two paratypes of K. flemingi , same data as holotype ( GNS TM1205 , TM 1208 ).

Other, non-type material. South Georgia Islands: Grytviken Bay , 54°16′53.4”S, 36°30′28.8″W SGI01 ( WAM S101182 p [M475, SK282]); Husivk 54°10.76’S, 36°42.68’W ( NHMUK 1994092 p [SK204]). NZ: Auckland Island, 50°34‘38.4“S 166°10‘01.5“E ( AM C.43852 2d; C.586004, 2 p). MI: ( AM C.46754 p [SK550 K9200 protoconch F12]). Garden Cove, 54°30’S, 158°57’E ( AM C.265944 4d, C.220182 d [R.211181], C.91954 10+p, C.91973 p, C.91974 p, C.46727 d, C.46701 3d); North Garden Cove, 54°29.91’S, 158°56.45’E ( AM C.91965 10+p, C.91964 10+p, C.91963 10+p, C.91966 10+p); Hasselborough Bay, 54°29.91’S, 158°56.08’E ( AM C.91970 10+p, C.91971 10+p, C.91969, C.91967 10+p), Hasselborough Corner ( AM C.91968 10+p); Buckles Bay, 54°30.04’S, 158°56.18’E ( AM C.91962 10+p, C.585698 MI02 8p, C.584960 p [M468], C.584961 p [M469], C.584962 p [SK272]); Opposite Tern Rock ( AM C.91959 10+p, p [SK202], C.91958 10+p, C.99957 6p); Cosray Rocks ( AM C.91955 10+p); Mawson Point, ( AM C.91952 10+p); Sandy Bay, 54°34’S 158°56’E ( AM C.91953 10+p, C.586003 p) .

Taxonomic remarks. The type of S. lateralis was subsequently figured in Gould (1856: 12, pl. 30, fig. 462, 462a–b). The holotype matches shell profile, dimensions and colouration of the figured specimen well. In an integrated morphological and molecular study Güller et al. (2015) established the identity of S. lateralis and its distinction from S. lessonii and S. fuegiensis . Hubendick (1946: 27) pointed out that various nominal species with shells resembling S. lateralis have been reported from the south Pacific between Australia, NZ and the Kerguelen. Building on the findings of Güller et al. (2015), our anatomical and molecular analyses of freshly preserved topotypic specimens matching the types of each nominal species validate the identity and occurrence of S. lateralis and establish K. innominata (TS, Fig. 29K ) and K. macquariensis (TS, Fig. 29J ) as new synonyms. The identity of other nominal species described from this region, such as S. flemingi , S. stewartiana , S. redimiculum and S. macgillvrayi remain uncertain and are not reviewed herein. Güller et al. (2015: 88) stated that due to provenance issues and character differences, the name S. redimiculum is likely not applicable to Siphonaria species from the South American region, while assigning the Magellanic records of S. macgillivrayi in Hubendick (1945; 1946) to S. fuegiensis . Iredale (1915: 478) introduced the new name Kerguelenia innominata for ‘ Siphonaria lateralis from the subantarctic islands of New Zealand’ as described by Suter (1913: 601, pl. 49, fig. 10). Subsequently, Powell (1955: 122) considered Kerguelenia innominata Iredale 1915 as a nomen nudum. However, it is a replacement name based on a detailed description (of S. lateralis ) by Suter (1913) and therefore an available name (Art. 12.2. of The Code). Suter (1913: 601) also included S. redimiculum Reeve, 1856 and S. tristensis Leach (not Sowerby I, 1823) in the synonymy of S. lateralis . However, Tasmania is considered as an unlikely occurrence for a species otherwise distributed through the sub-Antarctic. The genus name Kerguelenella was introduced by Powell (1946: 91) as a replacement name for Kerguelenia with S. redimiculum Reeve, 1856 as the type species by original designation. Powell (1955: 120–122; 1979: 293–294), Dell (1964: 290–292), and Forcelli (2000: 132) treated this taxon as an accepted genus. Powell (1955: 122) treated K. macquariensis as a subspecies of K. lateralis stating that K. macquariensis is ‘closer to K. lateralis than any other NZ form’. This was followed by Powell (1960: 168) and Dell (1964: 291). However, subsequently ( Powell, 1979: 293) synonymised K. macquariensis with K. lateralis .

Boreham (1959: 71) subsequently designated the lectotype of Kerguelena innominata restricting the type locality to Disappointment Island, Auckland Islands. A note on the lectotype label ( GNS TM1203) indicates ‘nom. nov. for Siphonaria lateralis Suter (not S. lateralis Gould, 1846 ) (in part) Ex Suter colln 4015’. Powell (1979: 293, pl. 54, figs 16–17) considered Kerguelenella innominata as an accepted species. Dell (1964: 290) considered S. magellanica as a synonym of S. lateralis ; however, Güller et al. (2015: 83) showed it to be a synonym of S. lessonii instead.

External morphology ( Fig. 29P ). Foot sole orange grey, paler to foot edge; foot wall grey to yellow green, cephalic folds and pneumostomal lobe paler, fold small; irregular blotches of black pigmentation around foot wall and cephalic folds.

Shell ( Figs 29H–L ; Table S9). Medium to large sized (max sl mean = 15.8 mm, SD = 2.3 mm, n = 8, MI specimens), elongate ovate; height medium; exterior uneven, smooth to undulating often wrinkled, radially ribbed, reddish to greenish brown, apex offset strongly posterior and left, anterior and right apical sides strongly convex, posterior and left apical sides shorter straight to concave; protoconch hooked, below apex, close to posterior edge; protoconch direction weakly heterostrophic (n=1; Fig. 29T ); growth striae prominent in bands, shell thin, lip even fragile, periostracum freely extending; rib count (mean = 31, SD = 2.5, n = 8), primary ribs flatly rounded, not protruding beyond shell lip; often interspersed finer secondary ribs, rib interstices darker; siphonal ridge indistinct but may be bulged, formed by paired primary ribs. Interior glossy, shell margin dark brown to tan, lip paler, paler markings weakly highlight under ribs, siphonal groove distinct, shallow, same colour as margin; spatula mottled tan, uneven darker markings; ADM scar distinct, CMS straight; thickening of shell lip not observed.

Reproductive system ( Figs 30E, G; n = 3). RS positioned within right side of coelom under the respiratory cavity, hermaphroditic glands positioned to posterior against right foot wall and over foot sole, epiphallic parts positioned between over rear of BM and side RAM, tip of AO embedded in EG; ED large wide short centrally curved, EG indistinct and curved continuation at top of ED, no flagellum (F1); AO and GA merged in base of ED as protruding bulb with MA; epiphallic parts all muscular tissue; CD and BD both short wide muscular wall featureless slightly curved, jointly connect to AO on inner side, BD over CD; pass just within outer side of RAM, BC large rounded, positioned between footwall and AG, test thick opaque, filled with orange-brown gelatinous mass; CD enters AG close to BD; single puckered GP at end of GA; HD small, brownish coils, links AG to brownish finely granulated HG; MG and larger AG small folded soft white tissue, MG at anterior of AG; dark SV embedded within AG, sides match curvature of inner foot wall at right posterior quarter of coelom.

Spermatophore ( Fig. 30F ). Elongated drop shaped, test thin, translucent (length = 4.4 ± 1.5 mm, n = 2), head bulbous, broad, tip bluntly rounded, containing a white gelatinous mass; taper region to flagellum reduced; both sections smooth, featureless; head much larger than flagellum (head length = 3.9 ± 1.3 mm, head length of SPM length ~88 %; head width = 1.06 ± 0.7 mm, flagellum width = 0.14 ± 0.03 mm, n = 2).

Radula and jaw. Described and figured in Güller et al. (2015: 87, figs 2D–F, 3G–H). Dentition formula 46:1:46 ( Hubendick 1946: 27).

Comparative remarks. Siphonaria lateralis ( lateralis group, unit 6) is the sister species of S. fuegiensis ; both species together form a well differentiated subclade in the mitochondrial tree ( Figs 1 , 4 ). They differ by COI distances of ≥ 6.9% (Table S8). Siphonaria lateralis differs from other species by COI distances of ≥ 18% (Table S8). Within the Australian and New Zealand subantarctic distribution of S. lateralis , we found one sympatric congener on Auckland Island, S. obliquata (refer to comparative remarks under that species). No congeners were found on MI. Topotypic specimens of K. innominata ( Fig. 29H , lectotype) and K. macquariensis ( Fig. 29K ) reveal typical features of S. laterialis , such as a relatively smooth ( Fig. 29I ) or rough shell ( Fig. 29J ), and corresponding RS structure, size and shape of epiphallic parts. They fall well within a very tight genetic cluster with sequences from South Georgia (unit 6; Dayrat et al. 2014: 266). Güller et al. (2015: 93) appeared to have mixed-up the species identifications when differentiating ‘units 5 and 6’ delineated in Dayrat et al. (2014: 259).

Figured specimens in Hubendick (1946: pl. 1, figs 22–25, from South Georgia) match shells of this species figured here ( Figs 29H–L ). The RS depicted herein ( Fig. 30E, G ) corresponds well with that depicted by Hubendick (1945: fig. 15) and Simpson (1977: 126, fig. 7). We found no noteworthy anatomical differences between specimens from South Georgia and MI ( Figs 30E, G ).

Distribution and habitat. Recorded from MI, south Pacific, southern Argentina and New Georgia, south Atlantic Ocean. In this study found at sheltered positions, clustered in crevices and hollows, on rocky shores at upper to mid littoral levels ( Fig. 29S ).

Figures

FIGURE 1. Maximum Likelihood phylogram based on analyses of a concatenated sequence data set of 16S and COI. Branches are collapsed at the species level. Branch labels give unit numbers and accepted species names. Numbers on branches indicate branch support employing 10,000 ultrafast bootstraps.Available genus-group names are shown next to their type species. Scale bar indicating modelled sequence divergence.

FIGURE 4. Maximum Likelihood phylogram (partial, species not collapsed). Clades C–F (normalis, lateralis and pectinata groups) of the tree shown in Fig. 1. Branch labels give specimen identifiers for new sequences or Genbank accession numbers for imported sequences from other studies and geographic regions (see Tables S1–S2 for details). Identical haplotypes are merged into single tips. Numbers on branches indicate branch support by employing 10,000 ultrafast bootstraps. Clade names give unit numbers and accepted species names. Scale bar indicating modelled sequence divergence.

FIGURE 29. Shells of S. plana, S. plicata and S. lateralis. A–D, M. S. plana. A. Lectotype MNHN-IM-2000-35955. B. Syntype of S. ferruginea NHMUK 1981001. C–D. Mauritius, Nth Albion, TS. C. AM C.584970 [M252]. D. AM C.584970 [M254]. M. In situ. E–G, N–O, Q–R. S. plicata. E. Lectotype MNHN-IM-2000-35956. F–G. Tonga, Ha’atafu Beach, TS of S. tongensis. F. AM C.585275 [M418]. G. AM C.585276 [M419]. N. Holotype of S. tongensis UUZM 1576. O. In situ. Q. Protoconch, AM C.585278 [SK225]. R. Animal, Halafuoleva Beach. H–L, P, S–T. S. lateralis. H. Lectotype of K. innominata GNS TM1203. I. Holotype of Kerguelenia macquariensis AWMM MA.70376. J–T. Macquarie Is, TS of K. innominata. J. AM C.584961 [M469, SK271]. K. AM C.584960 [M468, SK270]. L. AM C.91959 [SK202]. P. Animal. S. In situ. T. Protoconch, AM C.584962 [SK272]. Scale bars = 10 mm.

FIGURE 30. Reproductive morphology of S. plana, S. plicata, S. lateralis and S. radians. A–B. S. plana, Mauritius, AM C.584970 [M252]. C–D. TS of S. plicata, Tonga, Tongatapu. C. AM C.585276 [SK106, M419]. D. AM C.585275 [SK104, M418]. E–G. S. lateralis, Macquarie Island, TS of Kerguelenella innominata. E–F. AM C.91959 [SK202]. G. AM C.584960 [M468, SK270]. H–I. Indonesia, Riau Islands, Neotype of S. radians ZRC.MOL.24912 [M519, SK435]. Scale bars = 1 mm.