Hippasteria, TASMANICA MCKNIGHT, 2006, TASMANICA MCKNIGHT, 2006

Mah, Christopher, Neill, Kate, Eléaume, Marc & Foltz, David, 2014, New species and global revision of Hippasteria (Hippasterinae: Goniasteridae; Asteroidea; Echinodermata), Zoological Journal of the Linnean Society 171 (2), pp. 422-456: 426-434

publication ID

http://doi.org/ 10.1111/zoj.12131

persistent identifier

http://treatment.plazi.org/id/0395879A-1C0A-FFBB-FF0B-FB42B70468C6

treatment provided by

Carolina

scientific name

Hippasteria
status

 

STATUS OF HIPPASTERIA TASMANICA MCKNIGHT, 2006  

A taxonomic review of all nominal Hippasteria species   , including those taxa not sampled for COI, was undertaken to complement the phylogenetic survey. Most of these are treated in the Systematics section. However, Hippasteria tasmanica McKnight, 2006   , displayed characters, including a greater number of relatively flattened furrow spines (N> 2), spinelet-covered abactinal, marginal, and actinal surfaces, and toothed pedicellariae, which strongly indicated placement within the genus Evoplosoma   rather than Hippasteria   . This species was removed from the Systematics section and will be further dealt with in a later publication addressing Evoplosoma   .

HIPPASTERIA CALIFORNICA FISHER, 1905  

( FIGS 2A–F View Figure 2 , 3A–F View Figure 3 )

Fisher, 1905: 310; 1911: 233; H.L. Clark, 1913: 194; Alton, 1966: 1702; Lambert, 1978b: 62; Maluf, 1988: 34, 118; Mah et al., 2010: 285; Clark & Jewett, 2011: 53 (in key as H. californica   ); Imaoka et al., 1991: 52 (as Cryptopeltaster lepidonotus   ).

Type specimen: Hippasteria californica Fisher, 1905   , holotype USNM 22339. Chaffee & Weitbrecht (1984) outlined a series of ‘paratypes’, which were not formally designated by Fisher (1905) as part of his original type series. These specimens were used later as part of an extended species description in Fisher (1911). Thus, they provide further data for Fisher’s concept of H. californica   but it is at most, contentious whether they are proper paratypes.

Comments

Hippasteria californica   has a widespread, but unusual occurrence pattern varying across differing depths, extending from the Aleutians to Canada and south to the Gulf of California (Baja California). Two individuals of H. californica   were collected from British Columbia at relatively shallow depths (25–30 m). One of these specimens, CASIZ 185562, clusters with H. californica   ( Fig. 1 View Figure 1 ), whereas another specimen, CASIZ 185563, did not yield sequence data but is morphologically identical to CASIZ 185562. This is in contrast to other occurrence records of H. californica   , which are present from the Aleutians to Baja California at continental shelf to upper bathyal depths, sometimes as deep as 1820 m. Alton (1966) observed the ‘depth of capture’ range for H. californica   in northern Oregon at 411–1463 m (225–800 fathoms) vs. H. spinosa   (now H. phrygiana   ) captured at 140–457 m (76–250 fathoms). The two British Columbia specimens indicated above (CASIZ 185562, 185563) share morphological resemblance with H. phrygiana   in that they possess more quadrate marginals and a more strongly calcified body wall relative to deeper-water representatives of H. californica   , which have more rounded, ovalate marginals, spiny granules, and a less calcified body wall.

Other larger specimens of Hippasteria   examined from British Columbia (e.g. CASIZ 113374, 113375) have been identified as H. phrygiana   (= H. spinosa   ) but show characters intermediate or similar to those in H. californica   . Marginal plates were more rounded in outline and abactinal and actinal spinelets were finer and more delicate. We did not further sample Hippasteria spp.   from British Columbia but the molecular and morphological data are puzzling. Further studies of Hippasteria   in the British Columbia region remain to be performed but the morphology and distribution may reflect disjunct distribution events, such as those seen in the asterinid Patiria miniata   for Washington and Oregon ( Keever et al., 2009).

Two specimens of H. californica   from the Gulf of California (1555 m) are supported together on a branch separately from other H. californica   suggesting isolation from the more northern population. These specimens showed a more stellate shape with more pronounced radial spines along the arm surface.

A scleractinian coral Javania borealis   ( Flabellidae   ) was observed in the mouth and tube foot furrow of CASIZ 120096 (from Patton Seamount).

Occurrence

Gulf of California (Baja), Southern California , Washington to British Columbia , Aleutian Islands (Alaska) to Patton Seamount, Gulf of Alaska, and Hokkaido, Japan 110–2373 m. As shallow as 30 m in British Columbia   .

Description

Body moderately to strongly stellate, often depending on size (R: r = 1.5–2.3), arms triangular, but variably broad to narrow. Disk with rounded inter-radial arcs ( Fig. 2A View Figure 2 ).

Abactinal surface flattened to strongly tumescent (abactinal disk surface variably swollen at time of death). Fasciolar channels well developed amongst plates. Abactinal plates round to oval in outline with bare, smooth surface (other than peripherals). Plates large and small sized, both irregularly distributed. Largest plates present on disk centre; smallest plates present adjacent to contact with superomarginal plates. Individual abactinal plates with two to 35 evenly distributed, peripheral accessory granules, each quadrate to irregularly shaped. Accessory granules with jagged or notched surfaces, sometimes almost spineletlike. Plates with either low, round tubercles or large, prominent spines. Large, prominent, conical spines (approximately 2–3 mm in length) present primarily over basal arm region and along carinal series with irregular occurrence along arm. Some plates adjacent to radial series bare or with smaller spines projecting from central plate convexity. Bivalve pedicellariae large, distributed unevenly across abactinal surface. Pedicellariae clamp-like, valves variably smooth to jagged. Pedicellariae present on abactinal plates sitting across complete plate diameter; others present on plate in addition to large spine while present between plates within fasciolar channel. Papular pores present on arms and all of disk surface, including both radial/ inter-radial regions. Madreporite with four welldeveloped sides and one smaller, weakly developed one. Flanked by five abactinal plates. Sulci deep, well developed.

Marginal plates with lateral facing, number 24–36 from arm-tip to arm-tip. Marginal plates quadrate (at R = 2.5, e.g. USNM E10442 View Materials , Fig. 3D View Figure 3 ) to oval/ elliptical (R = 7.2, e.g. USNM E37188 View Materials , Fig. 3C View Figure 3 ) in outline. Marginal plate shape/outline varies widely amongst dif- ferent individuals from varying populations, differently sized specimens, and among arm location. Some smaller specimens have consistently quadrate marginal plates proximally to distally. Larger specimens with elliptical-shaped marginal plates most strongly expressed inter-radially. In some specimens, there are elliptical marginals inter-radially, but with distal marginals becoming more quadrate (e.g. CASIZ 101825). Those specimens with quadrate-shaped marginals throughout have all been relatively small (e.g. USNM E10442 View Materials , CASIZ 185562). All marginal plates with one to two (mostly one) large, conical spine present on the centre of each plate ( Figs 2C, G View Figure 2 ; 3D, E View Figure 3 ) but some specimens with two to four small, short spinelets present around base of primary spines (e.g. CASIZ 101825). Bivalve pedicellariae are not commonly encountered on marginal plates but they are observed at the spine base adjacent to short spinelets. All marginal plates bare save for the spines, spinelets, and pedicellariae ( Fig. 2C, D, F View Figure 2 ). Spine size and thickness variable amongst specimens throughout its range. CASIZ 113375 from shallower water has thickened, blunt, and very heavy spines ( Fig. 3D, G View Figure 3 ) vs. those specimens from Gulf of California (USNM 1215326, 1215327, 1215328) with finer, sharper, and lighter spines ( Fig. 3A View Figure 3 ). Spines are present on each plate series in ordered sequence appearing to form a complete fringe around the edge of the animal. Periphery of all marginal plates with accessory granules nearly identical to those present on the abactinal plates save for a small round tubercle that is present on approximately two to three plates per inter-radius. Superomarginal plates quadrate and wider in outline inter-radially but becoming more elongate with more strongly rounded edges making plates appear more circular in outline distally along the arms.

Superomarginal and inferomarginal correspondence varies. Some show direct 1:1 association interradially but become more offset distally along arms. However, others show an acutely offset arrangement between superomarginal and inferomarginal series ( Fig. 2C View Figure 2 ). Differing plate sizes between the two series has also observed. Accessory granules, 15–35 per plate, widely spaced, heterogeneous in size with spinelets, notches on each granule, all similar to those on abactinal and actinal plates. Pedicellariae not observed on marginal plates. Fasciolar channels shallow but well developed. Terminal plate triangular in shape, similar in size to distal-most adjacent superomarginal.

Actinal surface with four to five poorly defined, irregularly arranged chevrons ( Fig. 2B, E View Figure 2 ). Plates similar to those on abactinal surface, round to oval in outline with shallow but well-developed fasciolar groove contiguous with those present on marginal plates ( Fig. 2B View Figure 2 ). As with abactinal surface, each actinal plate with either a conical, pointed spine or a prominent, large pedicellariae. Each plate with three to 20 widely spaced accessory granules forming periphery of each plate. Each granule with tiny spinelets or notches. Actinal pedicellariae distinct in that valves possess eight to 15 interlocking teeth. These pedicellariae present on approximately 20–50% of the actinal plates ( Fig 2B View Figure 2 ).

Blunt to pointed furrow spines, one or two on each plate ( Fig. 2B, E View Figure 2 ), which forms an angular furrow margin. Two spines present on first one to two proximal adambulacral plates with one spine present on all plates to arm-tip. Every adambulacral plate with one large, wide (width> length) bivalve pedicellariae (clamplike) lacking teeth, present behind each furrow spine. Another large subambulacral spine is present behind or adjacent but offset to each adambulacral pedicellariae. On some proximal adambulacrals, a large pedicellariae with smooth valves replaces subambulacral spination altogether. Adambulacral plate extending from tube foot furrow to actinal surface with actinal furrow side bearing four to nine accessory granules similar to those elsewhere with spinelets. Oral plates each with four prominent thick spines projecting into oral furrow. Oral plate surface covered with four paired granules, quadrate to angular in shape. Distal end of oral plates with four to six accessory granules covered by short, sharp spinelets similar to those on actinal, marginal, and abactinal plates.

Colour in life is orange or red. Smaller individuals are white with orange highlights.

Morphological size variation

A clade supported within H. californica   was represented by two individuals, which were collected from shallow-water (20–30 m) in British Columbia (e.g. Fig. 2D View Figure 2 ). These specimens differed from prior accounts of H. californica   in two respects, their shallow depth occurrence and the distinct character differences. Most distinctive is the presence of quadrateshaped, swollen marginals, large conical spines, and bivalve pedicellariae, which are more similar to those in H. phrygiana   than those of H. californica sensu Fisher (1910)   . More consistent with H. californica   is the presence of pointed, almost spinelet-like granules on the actinal and marginal plates.

The disagreement between morphology and phylogenetic placement may be size-related. One specimen (CASIZ 113375) from British Columbia (42 m depth) with a much larger overall size (R = 12.0 cm) shows very distinctive elliptical marginal plates and spiny actinal granules as described for H. californica   by Fisher (1911). Two smaller specimens of H. californica   from off the coast of Oregon (USNM E10441 View Materials , E10442 View Materials ) with R = 1.9, R = 2.9 show quadrate-shaped marginal plates but are otherwise consistent with H. californica sensu Fisher (1911)   . The British Columbia specimens show much more heavily calcified marginals and spination than those in the Oregon specimens, which might be consistent with the amount of calcium carbonate available at differing depths.

Baja California /deep-sea variation

Three specimens from Baja California show several distinctive character differences associated with deeperwater forms that differ from shallower-water H. californica   . Individuals included in this branch are associated with deeper depths (and at least three specimens (USNM 1215326, 1215327, 1215328) represent the furthest known southern occurrence for H. californica   in the Gulf of California.

Two specimens are supported as sister taxa on a distinct clade in our tree ( Fig. 1 View Figure 1 ) and both were collect- ed from relatively deeper water settings (> 1000 m) than the other H. californica   included in our data. It seems likely that these two may represent more a widely occurring, deeper-water clade relative to other sampled individuals. Sampled individuals occur at the furthest extremities of H. californica’s geographic range with USNM 1215326 View Materials , 1215327 View Materials , 1215328 View Materials collected from the Gulf of California ( Fig. 4A View Figure 4 ) and USNM 1215325 View Materials from President Jackson Seamount C in the North Pacific ( Fig. 3C View Figure 3 )   .

These individuals show very distinct morphologies. USNM 1215326, 1215327, and 1215328 (the Baja population, Fig. 4A View Figure 4 ) specimens shows a strongly stellate shape (R: r = 3.16) vs. USNM 1215325 (the North Pacific population, Fig. 3C View Figure 3 ), which shows a more pentagonal shape (R: r = 1.85). The Baja H. californica   has finer, sharper abactinal, marginal, and actinal spines ( Fig. 3A, B View Figure 3 ), which are finer and sharper relative to the North Pacific specimen, which have more stout, and more blunt spination on the abactinal, marginal, and actinal surfaces ( Fig. 3 View Figure 3 C−F). Abactinal pedicellariae in the Baja specimens are also more elongate and clampshaped, whereas the North Pacific specimen has longer, more bivalve valves. Similarities between these two individuals are present but are relatively few, and largely associated with the actinal surface. The granules on the actinal surface on both individuals have pointed, almost spinelet-like tips. Actinal pedicellariae are more similar in shape between the two populations and also have teeth on each valve.

Adult specimens from Baja California (the above USNM 1215326, 1215327, 1215328) are very similar in appearance to relatively small individuals (R = 2.5) of H. californica   from the Gulf of Alaska (e.g. CASIZ 180785). Characters such as marginal plate shape, abactinal pedicellariae, abactinal and marginal spine shape, and strongly stellate body form (R: r) are similar or identical, suggesting possible ontogeny-related shifts between populations.

Material examined

Aleutian Island / Gulf of Alaska. CASIZ 120174   Gulf of Alaska 55°44.67′N, 135°22.33′W 662 m. Coll. R GoogleMaps   . VanSyoc 19.vii.1999 [one wet specimen (spec.) R = 5.3, r = 2.3, arms upturned]; CASIZ 120172   Gulf of Alaska 55°45.96′N 135°16.87′W 722 m. Coll. R GoogleMaps   . VanSyoc 19.vii.1999 (one wet spec. R = 4.6, r = 2.6, arms upturned). CASIZ 120096   Patton Seamount , Gulf of Alaska, (start) 54°20′45.5″N, 150°20′20.3″W to (end) 54°19′33.6″N, 150°21′54″W, 2373 m. R V GoogleMaps   Alvin, Dive 3432, 24.vii.1999. (one dry spec. R = 9.2, r = 4.6, but arms upturned). CASIZ 180785   Gulf of Alaska, 661–667 m, coll. NMFS   aboard F V Sea Storm (five wet specs R = 5.8, r = 3.3; R = 4.7, r = 2.1; R = 4.3, r = 1.9, R = 2.9, r = 1.4: R = 2.5, r = 1.4). British Columbia. CASIZ 113375   vicinity of Fitzburgh Channel, off Hakai Channel, British Columbia 42.0 m (23 fms), coll. W.F. Thompson (one dry spec. R = 12.0, r = 5.8); CASIZ 185562   Sechelt Inlet, Strait of Georgia, British Columbia, 49°32.89′N, 123°47.7′W, 30.0 m. Coll. Neil McDaniel xi.2011 (one wet spec. R = 3.1, r = 1.5); CASIZ 185563 GoogleMaps   Howe Sound , British Columbia. 49°21.43′N, 123°20.02′W, 25.0 m. Coll. D. Swantston 2011 (one wet spec. R = 3.2, r = 1.7). Pacific Northwest. USNM E37188 View Materials GoogleMaps   , south-west mouth of Columbia River, Oregon. North Pacific Ocean , 46°00′42″N, 124°47′18″W, 366 m (200 fms), coll. M. Alton aboard R V GoogleMaps   Commando (one dry spec. R = 7.4, r = 3.3); USNM E37189 View Materials   , south-west mouth of Columbia River, Oregon. North Pacific Ocean , 46°00′00″N, 124°44′00″W, 366 m (200 fms), coll. M. Alton aboard R V GoogleMaps   Cobb (four dry specs R = 12.1, r = 5.3; R = 9.5, r = 4.3; R = 8.8, r = 4.2; R = 9.1, r = 3.8); USNM E10441 View Materials   , south-west of Columbia River mouth, North Pacific Ocean , 46°2.7′N, 124°57.3′W, 915 m, coll. M. Alton aboard R V GoogleMaps   Commando (one dry spec. R = 1.9, r = 0.9); USNM E10442 View Materials   , south-west of Columbia River mouth, North Pacific Ocean , 45°55′N, 124°54′W, 732 m, coll. M. Alton aboard R V GoogleMaps   Commando (one dry spec. R = 2.9, r = 1.6); USNM 1215325 View Materials   President Jackson Seamount C, North Pacific 42°44′56.0″N, 128°5′11.8″W, 1373.9 m, coll. D. Clague, MBARI GoogleMaps   , 5.ix.2009 (one wet spec. R = 2.6, r = 1.4); CASIZ 121349   off the coast of Oregon, 43°27.8′N, 124°52′W, 600 m. Coll. A. Carey Jr aboard R V GoogleMaps   Cayuse (two wet specs R = 4.6, r = 2.6; R = 6.3, r = 3.7, arms upturned in both specs); CASIZ 101825   Monterey Bay , 36°49′N, 122°30′W, 366 m (200 fms) coll. R GoogleMaps   . Bolin 17.xi.1932 (one dry spec. R = 10.1, r = 3.8); CASIZ 105361   Monterey Bay, off Soberantes Point , 36°28′3″N, 122°17′4″W− 36°29′3″N, 122°20′W 1409 m. Coll. USNS GoogleMaps   DeSteiguer (one dry spec. R = ∼11.1, r = 7.3); CASIZ 111704   Monterey Bay canyon wall. 36°44.83′N, 122°2.39′W – 36°45.64′N, 122°3.94′W, 560 m. Coll. C. Mah, 17.x.1997 (one wet spec. R = 4.7 r = 2.5); CASIZ 115073 GoogleMaps   Fort Bragg, Mendocino County 969 m (530 fms) (one wet spec. R = 6.7, r = 3.9); CASIZ 142776   off Oregon coast 43°26′N, 124°53′W, 700 m, (two wet specs R = 4.1, r = 2.2; R = 5.8, r = 2.8, arms upturned). Gulf of California (Baja California). USNM 1215327 View Materials GoogleMaps   Gulf of California, Baja California 28°41′13.3″N, 112°58′23.8″W, 1555 m, coll. D. Clague, D348-A1 (one wet spec. R = 2.9, r = 1.0); USNM 1215326 View Materials GoogleMaps   Gulf of California, Baja California, 28°41′13.3″N, 112°58′23.8″W, 1555 m coll. D. Clague, D348-A2 (one wet spec. R = 3.8, r = 1.2), USNM 1215328 View Materials GoogleMaps   Alarcon Rise , Gulf of California, Baja California, 27°53′45.5″N, 111°58′2.3″W (27.895987, −111.967315), 1100 m. Coll. D. Clague (one wet spec. R = 3.4, r = 1.8) GoogleMaps   .

HIPPASTERIA FALKLANDICA FISHER, 1940  

( FIG. 4E–H View Figure 4 )

Fisher, 1940: 125; Bernasconi, 1963: 287; Clark & Downey, 1992: 246 (key); Mein, 1992: 245; Branch et al., 1993: 44, 60; Clark, 1993: 257; Larraín et al., 1999: 437; Stampanato & Jangoux, 2004: 4,6; McKnight, 2006: 97; Mah, 2011: 27.

Type specimen

Hippasteria falklandica Fisher, 1940   , holotype, NHM, London, 1948.3.16.330.

Comments

Hippasteria falklandica   tissue was unavailable for DNA sampling; however, morphology of H. falklandica   , including surface and marginal accessories ( Fig. 4 View Figure 4 F−H), supports a close relationship with H. heathi   based on characters outlined by Fisher (1940), including granulation, spine and pedicellariae morphology. This species is supported as having close affinities with H. heathi   . Summary descriptions of this species are found in Fisher (1940) and Stampanato & Jangoux (2004).

Occurrence

Falkland Islands (= Islas Malvinas), northern Argentina, Kerguelen , Marion and Prince Edwards Islands region , Straits of Magellan, south of Tasmania, approx. 49.375°S, 150.450°E. 149–1148 m GoogleMaps   .

Material examined

IE 2006-1165 Kerguelen Islands 49°32′S, 70°57′E, 149– 155 m, coll. A. Guille Navire Oceanographique Marion Dufresne GoogleMaps   MD04, station CP 13 (one dry spec. R = 9.4, r = 3.3)   .

HIPPASTERIA HEATHI FISHER, 1905  

( FIG. 4A–D View Figure 4 )

Fisher, 1905: 319; 1911: 231; Clark, 1993: 257; Krieger & Wing, 2002: 86; Mah et al., 2010: 286; Clark & Jewett, 2011: 53 (key).

Type specimen

Hippasteria heathi Fisher, 1905   , holotype USNM 22338 View Materials .

Comments

Our further taxon sampling has added two undescribed taxa to the branch containing H. heathi   with strong (100%) support. The distinctive spines, and pedicellariae ( Fig. 4A, C, D View Figure 4 ) observed in this species are most similar to H. mcknighti   but dissimilar to H. tiburoni   , which has much fewer and more sparsely occurring spines and pedicellariae, suggesting that morphology is relatively conservative amongst these widely occurring species. Krieger & Wing (2002) reported H. heathi   as a predator of primnoid octocorals. These closely related taxa may display similar habits.

Occurrence

Alaska, Aleutians, Gulf of Alaska. 214–454 m.  

Description

A description of H. heathi   is found in Fisher (1911).

Material examined

Holotype USNM 22338 View Materials , Guard Island, Behm Canal, Alexander Archipelago , Alaska, 55°N, 131°W, 377– 454 m, coll. USFC Albatross , 9.vii.1903 (one dry spec. R = 7.8, r = 3.9). CASIZ 164066 Aleutian Islands , 52°38′42.72″N, 172°16′23.15″W; 52°39′23″N, 172°15′44.64″W. 393 m. Coll. R. VanSyoc 22.vii.2002 (one wet spec. R = 7.1, r = 3.0). GoogleMaps  

R

Departamento de Geologia, Universidad de Chile

V

Royal British Columbia Museum - Herbarium

USNM

Smithsonian Institution, National Museum of Natural History

USFC

U. S. Fish Commission

Kingdom

Animalia

Phylum

Echinodermata

Class

Asteroidea

Order

Valvatida

Family

Goniasteridae

Loc

Hippasteria

Mah, Christopher, Neill, Kate, Eléaume, Marc & Foltz, David 2014
2014
Loc

HIPPASTERIA

FALKLANDICA FISHER 1940
1940
Loc

Hippasteria falklandica

Fisher 1940
1940
Loc

Hippasteria falklandica

Fisher 1940
1940
Loc

H. falklandica

Fisher 1940
1940
Loc

HIPPASTERIA

CALIFORNICA FISHER 1905
1905
Loc

HIPPASTERIA

HEATHI FISHER 1905
1905
Loc

Hippasteria heathi

Fisher 1905
1905