1,721,327 research outputs found
Parvamussium scitulum
No full textParvamussium scitulum (E.A. Smith, 1885) Figures 16 A–E Amussium scitulum E.A. Smith, 1885: p. 312, pl. 23, figs. 4 A–B. Parvamussium scitulum (E.A. Smith, 1885) — Okutani, 2000: p. 913, pl. 454, fig. 7; Raines, 2002: p. 32, fig. 36; Dijkstra & Maestrati, 2008: p. 94; Dijkstra & Maestrati, 2010: p. 339; Huber, 2010: p. 224. Material examined. Several articulated specimens and over one hundred single valves from EI (BK), plus specimens from New Guinea (BK), Fiji (BK), the Philippines (MHU) and Okinawa (BK). Diagnosis. Shell small, thin and flattish; valves unequal, with the RV smaller than LV. Exterior surface sometimes with irregular sculpture or radiating ridges and commarginal growth striae. Interior of both valves with 7–11 internal ribs. Auricles subequal. Color of LV cream with white or yellow-brown maculations; RV cream colored. Remarks. Although the EI specimens are somewhat smaller, they conform well to P. scitulum from Okinawa, Japan and New Guinea. Habitat. Commonly found at many locations around EI, in sand and rubble, from 50–150 m. Distribution. Parvamussium scitulum is a widely distributed species, which is known from New Guinea to Japan, including the Philippines, Indonesia, New Caledonia, Loyalty Islands, Fiji, Tonga and Easter Island. However, it has not been recorded from the Hawaiian Islands, New Zealand or the Kermadec Islands— E4.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on page 3
Neopycnodonte cochlear
No full textNeopycnodonte cochlear (Poli, 1795) Figures 13 A–B Ostrea cochlear Poli, 1795: p. 179, pl. 28, fig. 28. Ostrea laysana Dall et al., 1938: p. 111, pl. 32, figs. 5–8. Ostrea laysana Dall et al., 1938 — Kay, 1979: p. 538. Neopycnodonte cochlear (Poli, 1795) — Oliver, 1992: p. 89, pl. 16; Huber, 2010: p. 185, fig. 8; Severns, 2011: p. 464, pl. 212, fig. 3. Material examined. Single very juvenile upper valve (6.2 mm) from EI (BK), plus specimens from the Hawaiian Islands (MHU). Diagnosis. Shell small to medium, suboval to subcircular, inequivalve, inequilateral, somewhat fragile. Upper valve flat and much smaller than the concave lower cemented valve. Exterior surface of commarginal ridges and irregular laminar layers. Interior margin typically with vermicular chomata on both sides of the resilifer. Color variable, buff to yellowish green. Remarks. Although quite small, this single upper valve matches in texture, muscle scar, chomata and hinge very well. It is expected that deep water trawls will provide additional and larger material given the species prefers deeper water. Habitat. Found at 100 m at Ovahi, EI. Distribution. This deep water species is widely distributed. Although originally described from Sicily, Italy, Neopycnodonte cochlear is also known from the Red Sea, eastern Africa, Japan, the Hawaiian Islands and Australia. However, it has never been recorded from western America, New Zealand, or the Kermadec Islands. Easter Island is now considered a range extension— E5.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on page 2
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Isognomon (Parviperna) nucleus
No full textIsognomon (Parviperna) nucleus (Lamarck, 1819) Figures 11 C–D Perna nucleus Lamarck, 1819: p. 68. Perna pectinata Reeve, 1858b: sp. 2, pl. 1, fig. 2. Isognomon pectinata — Osorio, 1995: p. 200, figs. 2–3, 5; Tröndlé & Boutet, 2009: p. 5. Isognomon nucleus (Lamarck, 1819) — Tröndlé & Boutet, 2009: p. 5. Isognomon (Parviperna) sp. cf. nucleus (Lamarck, 1836) — Brook & Marshall, 1998: p. 212; Spencer et al., 2011: p. 1. Isognomon (Parviperna) nucleus (Lamarck, 1819) — Oliver, 1992: p. 68, pl. 11; Huber, 2010: p. 176, fig. 6. Material examined. Illustrations of the two live collected specimens, and one pair of matching valves, which were provided to us for this study (Osorio, pers. comm., 2010). Diagnosis. Shell small, obliquely-subovate, fairly solid and not fragile. Exterior surface of course commarginal lamellae, and usually encrusted. Interior smooth and nacreous, ventral margin the same color as the exterior. Hinge stout, consisting of numerous elongate teeth. Color variable, brownish-purple to greyish-black. Remarks. Isognomon (Parviperna) pectinata was synonymized with P. nucleus by Lamy (1933), and accepted by subsequent authors. The species recorded as I. pectinata by Osorio (1995) matches the widely distributed P. nucleus well. Habitat. Two matching valves of a fresh dead specimen (14.3 x 12.5 mm) were collected from the intertidal zone, (near Vaihu), while two other live specimens (2.6 x 2.3 mm & 4.6 x 3.3 mm) were collected from a depth of 20 m, attached to a colony of Pocillopora (off Motu Kaokao). Distribution. Isognomon (Parviperna) nucleus is widely distributed throughout the Indo-Pacific, from South Africa to the Kermadec Islands including the Society Islands, Marquesas Islands, Tuamotu Archipelago, Gambier Islands, Austral Islands, Pitcairn Islands, eastern Australia and Easter Island. However, it is not known from the Hawaiian Islands— E5.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on pages 25-2
Isognomon (Isognomon) incisum
No full textIsognomon (Isognomon) incisum (Conrad, 1837) Figures 11 A–B Perna incisa Conrad, 1837: p. 245, pl. 19, fig. 9. Isognomon (Melina) incisa (Conrad, 1837) — Dall et al., 1938: p. 64, pl. 13, figs. 1–8. Isognomon incisum (Conrad, 1837) — Kay, 1979: p. 520, figs. 167 E–F; Osorio, 1995: p. 200, figs. 1 & 4; Severns, 2011: p. 446, pl. 203, fig. 2. Material examined. Illustrations of the two live collected specimens, which were provided to us for this study (Osorio, pers. comm., 2010). Diagnosis. Shell medium in size, stout, and irregularly ovate. The LV larger and more inflated than the RV. Surface consisting of fine commarginal lamellae and low broad radial ribs. Well developed byssal notch. Hinge line straight with five to six elongate-transverse teeth. Color variable, with the margins often quite dark. Remarks. This species as well as the next isognomonid were first recorded by Osorio (1995). Although additional examples have yet to be collected by other workers, these specimens were found at opposite ends of the island and collected during separate trips. This would infer that the two species are naturally occurring and not a by-product of human activities. Habitat. One specimen (30.8 x 30.9 mm) was collected from the intertidal zone, byssally attached to the underside of a rock (Anakena), while another specimen (8.3 x 9 mm) was collected from a depth of 20 m, attached to a colony of Pocillopora Lamarck, 1816 (off Motu Kaokao). Distribution. Isognomon incisum was originally described from the Hawaiian Islands, but also collected live from Easter Island. Recent reports from offshore Panamic Islands should be instead refer to as I. recognitus (Mabille, 1895) (Coan, pers. comm., 2010)— E2.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on pages 24-2
Spondylus orstomi Lamprell & Healy 2001
No full textSpondylus orstomi Lamprell & Healy, 2001 Figures 18 C–F Spondylus orstomi Lamprell & Healy, 2001: p. 120, figs. 3 D–G. Spondylus cf. orstomi Lamprell & Healy, 2001 — Raines, 2002: p. 35, fig. 42. Spondylus orstomi Lamprell & Healy, 2001 — Huber, 2010: p. 220, figs. 3–4. Material examined. Several single valves and fragments from EI (BK), plus the MNHN type material. Diagnosis. Shell small to medium, elongate ovate, moderately thin, and inequivalve; auricles relatively small. Sculpture consisting of 12–16 well defined, low, rounded, primary radial ribs with 1–3 secondary riblets in the interstices. Both ribs and interstices covered in densely imbricated spines, with some spines occasionally being longer, thin and upright. Color variable from uniformly light brown, orange and bright yellow to maculations of orange and white. Remarks. Since the first report of this species at EI by Raines (2002), more valves have been collected, so we can now confirm that the species is indeed S. orstomi. Habitat. Occasionally found at several locations around EI, in sand and rubble, from 30–50 m. Distribution. Although Spondylus orstomi was originally described from New Caledonia, this deep water species has a much wider distribution. It is known from the Coral Sea, Philippines, and off China. The maximum size currently known is 60.6 mm from its furthest range in the East China Sea (coll. MHU). It has not been recorded from the Hawaiian Islands, New Zealand or the Kermadec Islands— E4.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on page 3
Dimya mimula Dall, Bartsch & Rehder 1938
No full textDimya mimula Dall, Bartsch & Rehder, 1938 Figures 13 C–D, 14 E–F Dimya mimula Dall et al., 1938: p. 78, pl. 19, figs. 1–2. Dimya mimula Dall et al., 1938 — Severns 2011: p. 454, pl. 207, fig. 2. Material examined. Several single valves (4.5 to 6 mm) from EI (BK), plus the Hawaiian USNM holotype of D. mimula. Diagnosis. Shell small, orbicular-elongate, inequivalve. RV attached to the substrate, no byssal foramen. LV sculptured with somewhat scaly radial riblets. Prodissoconch somewhat worn, but appears round and smooth. Interior of adult valves with finely denticulate margins. Two distantly placed elongate muscle scars, with the posterior bilobed. Yellowish white outside, whitish inside. Remarks. Dimya mimula is an exceedingly rare species. As far as is known, this is the first time it has been recorded since its description from a single upper valve collected from a depth of 235 m. The upper valves of the EI specimens match the USNM holotype of D. mimula (Figs. 14 E–F) well and the largest valve (13.8 mm) also reaches nearly its 14 mm size. The radial surface sculpture is characteristic for this species. The bilobed posterior scars are well visible (Figs. 13 D, 14 F). The rounded contour, yellowish color and notably the characteristic dense crenulations along the outer margins (Fig. 13 D) are all consistent with D. mimula. Habitat. Occasionally found at several locations around EI, in sand, from 30–80 m. Distribution. Dimya mimula was previously only known from the Hawaiian Islands, but has now been extended to Easter Island— E2.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on page 3
Limaria (Limatulella) Sacco 1898
No full textLimaria (Limatulella) sp. Figures 23 A–C Limaria parallela (Dall et al.) — DiSalvo et al., 1988: p. 459. Material examined. One live taken specimen and two single valves (5 to 9 mm) (BK). Diagnosis. Shell small, less than 10 mm, obliquely-ovate, equivalve, thin and fragile. Valves oblique, moderately inflated and not gaping. Exterior surface consisting of numerous (ca. 35) fine radial ribs, crossed by fine commarginal striae. Color translucent white. Remarks. Limatulella encompasses species related to Limaria s.s. It is smaller, somewhat less ventricose, thinner, with very numerous radial ribs, but with closed or nearly closed valves. The limatulellid shape, the small size, the inflation and the non-gaping structure place this species in Limatulella. No respective species is known from the Hawaiian Islands, but two larger species Limaria (Limatulella) amakusaensis (Habe, 1960), L. viali (Jousseaume in Lamy 1919), are known from the Indo-Pacific and Japan. Unfortunately, the minute size, limited material and the barely known variability of its congeners makes a comparison or a new description exceedingly difficult. The Limaria (Promantellum) parallela (Fig. 23 B) recorded by DiSalvo et al. (1988) is not L. (P.) parallela at all, but it is consistent with the subgenus Limatulella. Habitat. Currently only found off the western coastline of EI, in sand and rubble, from 20–150 m. One live taken specimen collected at 100 m. Distribution. At present this Limaria (Limatulella) sp. is only known from Easter Island— E1.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on pages 46-4
Funafutia levukana
No full textFunafutia levukana (E.A. Smith, 1885) Figures 24 E–G Lucina levukana E.A. Smith, 1885: p. 181, pl. 13, fig. 6. Funafutia levukana (E.A. Smith, 1885) — Glover & Taylor, 2001: p. 286, figs. 22 A-D; Tröndlé & Boutet, 2009: p. 8. Material examined. More than fifty single valves from EI and SyG (BK), plus specimens from the Marquesas Islands (MHU). Diagnosis. Shell small (up to 6 mm in length), suborbicular, equivalve, inequilateral, not fragile. Umbones elevated. Exterior surface of irregularly spaced prominent, rounded commarginal lamellae, microscopic radials. Interior smooth with continuous pallial line; margins finely crenulate. Hinge stout, consisting of two cardinals in the LV, and one cardinal in the RV with prominent posterior and anterior laterals. Color white. Remarks. The oblique shape, lamellate sculpture with microscopic radials, the crenulated margin and the hinge configuration closely approach the type species Funafutia levukana (E.A. Smith 1885). Species within the genus Levukana are typically known from shallow water to 40 m, with a size of 6 mm. The EI species is known from 20–100 m, also from caves in 35–40 m (Motu Tantara) with a maximum size of 5 mm. Although the EI material has a somewhat denser commarginal sculpture with weaker radials and a slightly less pronounced anterior lateral in the LV, J. Taylor, (pers. comm., 2010) confirmed the specimens to be within the normal variability of F. levukana. Sizes and depths are comparable. Most likely, this species conforms to Kay (1995: 155) Lucina species from Easter Island. Habitat. Commonly found at many locations around EI and SyG, in fine sand, from 20–100 m. Distribution. Funafutia levukana is known from eastern Africa to the Marquesas Islands, but has not been recorded from the Hawaiian Islands. The presence of this species on Easter and Salas y Gómez Islands represents a range extension— E4.Published as part of Raines, Bret & Huber, Markus, 2012, 3217, pp. 1-106 in Zootaxa 3217 on page 5
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