Five new species and one new genus of recent miliolid foraminifera from Raja Ampat (West Papua, Indonesia)

Genus Dentoplanispirinella Förderer and Langer gen. nov.

urn:lsid:zoobank.org:act:98A1DD41-C0AE-4401-830B-0D189E70661A

Description. Test small, broadly circular in outline, discoidal to slightly biconvex. Periphery with a weakly developed subrounded keel that encircles the entire test margin. Wall thick, calcareous, porcelaneous, imperforate. Coiling involute, throughout planispirally enrolled with 2.5 to 3.5 tubular chambers per whorl, each whorl slightly offset to the proceeding coil with a tendency to become sigmoiline (axial section as seen in CT scan, Fig. 2H). Lateral wall extensions of the adult chambers entirely cover the earliest chambers and tend to overlap the umbilical region in each whorl. Sutures oblique, thin and irregular. Aperture arch-shaped, triangular in juvenile specimens, high and subtriangular in adult specimens, tapering apically, on the base connected with the peripheral margin of the proceeding chamber and provided with a very small and thin tooth. In juvenile specimens the tooth appears just like a little knob or slightly raised spine.

Type species. Dentoplanispirinella occulta sp. nov.

Remarks. Dentoplanispirinella gen. nov. resembles Planispirinella Wiesner, 1931 in having a discoidal shape, a high aperture and a planispiral chamber arrangement, but differs from Planispirinella by the presence of a tooth and the more biconvex test shape in apical view (Fig. 2B). The apertural features and the coiling mode of Dentoplanispirinella further distinguish it from Nummoloculina Steinmann 1881, which has an apertural flap and an early quinqueloculine coiling.

Etymology. From the Latin “occultare” meaning for “hiding.”

Material. 28 specimens from nine samples (MR18, MI05, MI06, MS03, MS04, MG, M21, U16, Y24; Fig. 1C; Table 1), recent.

Holotype. The specimen illustrated here as Figs. 2C and 2D (sample MS03; MaLaPNG 2011–10).

Paratype. The specimen illustrated here as Figs. 2A and 2B (sample MS03; MaLaPNG 2011–10).

Type locality. The holotype and the paratype are from sample station MS03 (16m), a sand channel between Arborek Island and Pulau Mansuar; Raja Ampat, New Guinea (Indonesia).

Diagnosis. A species of Dentoplanispirinella gen. nov. with a discoidal to biconvex test shape, a slightly keeled periphery, a radial oriented, finely striate surface ornamentation and an arch-shaped, triangular aperture, provided with a small tooth.

Dimensions. Observed range of test dimensions: diameter 285–704 µm (lateral view), test width 100–193 µm (apertural view).

Occurence. Dentoplanispirinella occulta is widely distributed in the Raja Ampat area in fine to coarse coral rubble samples from depths of 14 to 45 m.

Description. Test porcelaneous and imperforate. Almost circular in lateral view, lenticular and biconvex in apertural view with a slightly developed, subrounded keel and weakly inflated chambers. Coiling planispiral and involute. Two and a half to three and a half chambers visible from the exterior. Lateral wall extensions of the adult chambers entirely cover the earliest chambers and tend to overlap the umbilical region; the final chamber covers approximately half of the test surface. Sutures oblique, thin, irregular and recurved near the periphery. Test surface ornamented with radial oriented, fine, sub-parallel to anastomosing striae that are straight to slightly curved backwards, towards the outer margins of the chambers. Umbilical region and test periphery more weakly ornamented. Outer wall layer constructed of longitudinally aligned needle-shape crystals, oriented perpendicular to direction of ornamentation. The test appears matte white under the light microscope with a slightly translucent periphery. Apertural face not ornamented. Aperture arch-shaped and triangular in juvenile specimens, high and subtriangular in adult specimens, tapering apically, on the base connected with the peripheral margin to the preceding chamber and provided with a peristomal rim. Aperture provided with a very small and thin tooth, with the flat side oriented in lateral direction.

Remarks. Dentoplanispirinella occulta sp. nov. differs from Planispirinella involuta Collins (1958, p. 374, pl. 4, Figs. 2A and 2B) by its more lenticular biconvex shape in horizontal section, the subtriangular shape of the aperture, the presence of a small tooth, and the striate surface ornamentation.

Genus Miliolinella (Wiesner, 1931)

Etymology. The new species is named after the indigeneous Moi people from Malaumkarta, a Papuan tribe from the north coast near Sorong.

Material. 11 specimens from six samples (B14, B15, E23, MR17, N18, U16; Fig. 1C; Table 1), recent.

Holotype. The specimen illustrated here as Figs. 3A–3C (sample B14; MaLaPNG 2011–11).

Paratypes. The specimens illustrated here as Figs. 3D–3F (sample B14), Figs. 3G–3I and Figs. 3J–3J (sample ER23; MaLaPNG 2011–11).

Type locality. The holotype and the paratype are from sample station B14 (41 m), Bag Island, east of Pulau Uranie; Raja Ampat, New Guinea (Indonesia).

Diagnosis. A slightly enlongated, medium-sized species of Miliolinella Wiesner, 1931 with a compressed, angular and slightly slanted outline, a smooth and shiny wall, and a high subcircular opening.

Dimensions. Observed range of test dimensions: test height 409–554 µm, test width 278–396 µm (lateral view), 166–250 µm (apertural view).

Occurence. This species is widely distributed in the Raja Ampat area in fine to coarse coral rubble samples and occurs at depths between 12 and 45 m.

Description. Test porcelaneous and imperforate, ovate in outline and slightly higher than broad. Test weakly compressed and flattened, subtriangular in apertural view. Chamber arrangement quinqueloculine with five chambers visible from the exterior. In some specimens only three to four chambers are visible. Periphery rounded to subrounded, chambers slightly inflated. Sutures curved, distinct and weakly depressed. Chambers tend to be off-centered, giving them a slanted appearance. Test wall smooth, translucent to opaque and glossy under the light microscope. Aboral end of the chambers slightly constricted. Aperture in basal position, a Miliolinella-type large subcircular opening with an everted peristomal rim and a semicircular, slightly excavated flap, that covers more than half of the opening.

Remarks. Miliolinella moia sp. nov. differs from Miliolinella pilasensis McCulloch, 1977 (p. 566, pl. 238, Fig. 16 and Loeblich & Tappan, 1994, p. 57, pl. 99, Figs. 1–9) in its angular and more compressed outline, and the large subcircular opening. Millet (1898) depicted a species of Miliolina valvularis (Reuss) from the Malay Archipelago (p. 11, Figs. 5A–5C) that shows a high degree of similarity to Miliolinella moia, but his specimen has a more rounded periphery. The original description of Triloculina valvularis by Reuss (1851, p. 85, pl. 7, Fig. 56) shows a specimen with a broadly rounded periphery and inflated chambers without angles. Miliolinella sp. 2 figured in Parker, 2009 from Ningaloo Reef, Australia (p. 128, Figs. 92A–92I, 93A–93J, 94A–94K) differs from Miliolinella moia by the low apertural opening and the broadly rounded and more inflated chambers.

Etymology. After the undulate ornamentation of the test. From the Latin “unda” meaning wave and mythological “Undine,” a term established by the Renaissance alchemist Paracelcus for water spirits.

Material. Three specimens from three samples (MR18, N18, U16; Fig. 1C; Table 1), recent.

Holotype. The specimen illustrated here as Figs. 4A–4C (sample MR18; MaLaPNG 2011–12).

Paratypes. The specimens illustrated here as Figs. 4D–4F (sample N18) and Figs. 4G–4I (sample U16; MaLaPNG 2011–12).

Type locality. The holotype is from sample station MR18 (18 m), east of Kawe Island. The paratypes are from sample stations N18 (30 m), south-west coast of Pulau Wayag, and U16 (45 m), between Pulau Uranie and Bag Island; Raja Ampat, New Guinea (Indonesia).

Diagnosis. A small quinqueloculine species of Miliolinella Wiesner with inflated chambers, a rounded outline and an undulate to reticulate surface ornamentation.

Description. Test porcelaneous and imperforate, small, ratio of height and width variable but usually slightly higher than broad. Periphery rounded and chambers slightly inflated. Chamber arrangement quinqueloculine, with five chambers visible from the exterior. Aboral end rounded, flush with the surface in the holotype to slightly raised in paratypes. Wall smoothly finished, matte, translucent under the light microscope. Sutures curved and depressed. Test surface ornamented with numerous irregular, predominantly longitudinal, somehow honeycombed reticulate to undulate low anastomosing costae that are covering large parts of the test. Outer-wall layer constructed of needle-shaped crystals that are primarily aligned in longitudinal direction. Aperture basal, a large semicircular Miliolinella-type opening, provided with a thickened and everted peristomal rim and a broad, slightly excavated basal flap.

Dimensions. Observed range of test dimensions: test height 146–162 µm, test width 114–224 µm (lateral view), 81–119 µm (apertural view).

Occurence. Miliolinella undina is present with one specimen in each of three highly diverse, miliolid-rich, fine coral rubble samples from depths of 18 to 45 m.

Remarks. Specimens of Miliolinella undina sp. nov. have been previously documented by Haig, 1988a as Miliolinella sp. B from the Papuan Lagoon, Port Moresby and by Hatta & Ujiié, 1992 as Miliolinella sp. from the Ryukyus. Hatta & Ujiié mentioned the species to occur rarely in their assemblages. The new species has also been recorded in samples from northern Palawan (M Förderer, 2016, unpublished data). Miliolinella cf. M. semicostata (Wiesner) depicted by Debenay from New Caledonia (2012, p. 110, 275) may also belong to Miliolinella undina, but shows a less undulated test ornamentation. Test shape, apertural and ornamental features are more similar to our holotype (Figs. 4A–4C) than to Miliolinella semicostata (Wiesner, 1923) from the Mediterranean Sea (see Cimerman & Langer, 1991, p. 42, pl. 38, Figs. 10–15). Miliolinella semicostata has less inflated chambers and the ornamentation is not reticulate but longitudinally striate and restricted to the angles. Miliolinella undina also resembles Miliolinella sp. 4 depicted by Parker from the Ningaloo Reef in Western Australia (2009, p. 136, Figs. 97A–97H), but his specimen has a less undulated and more striate alignment of costae. The new species also resembles Miliolinella flintiana (Cushman, 1932) (p. 55, pl. 12: 4A–4C) in size, test shape, chamber arrangement and apertural features. However it differs in its surface ornamentation, that is distinctly longitudinal costate in Miliolinella flintiana and undulate and more irregular in Miliolinella undina. Miliolinella flintiana also occurs in our assemblages.

Genus Triloculina D’Orbigny, 1826

2009 Triloculina? sp. 2—Parker, Ningaloo Reef, p. 372, Figs. 271F–271J.

Etymology. This species is named in honor of the indigeneous people of West Papua after the Kawe tribe, that owns and protects a highly diverse marine protected area of Raja Ampat.

Material. 12 specimens from seven samples (B15, FW, M05, MS04, N18, U16, Y25; Fig. 1C; Table 1), recent.

Holotype. The specimen illustrated here as Figs. 5A–5C (sample FW; MaLaPNG 2011–13).

Paratype. The specimen illustrated here as Figs. 5E–5G (sample FW; MaLaPNG 2011–13).

Type locality. The holotype and the paratype are from sample station FW (49 m), south-east Penemu, Fam Islands; Raja Ampat, New Guinea (Indonesia).

Diagnosis. A medium-sized species of Triloculina d’Orbigny with a slightly elevated “Lachlanella”-type aperture, rounded periphery, blunt angles and a roughly textured wall.

Dimensions. Observed range of test dimensions: test height 377–439 µm, test width 200–245 µm (lateral view), 162–195 µm (apertural view).

Occurence. This species is widely distributed in our sampling area in fine to coarse coral rubble samples from depths of 14 to 49 m.

Description. Test porcelaneous and imperforate, about one and a half times longer than broad. Broadly triangular in apertural view, ovate in outline. Chamber arrangement triloculine, periphery rounded to subrounded, chambers inflated with blunt angles. Sutures distinct and depressed. Surface ornamented with elongated, irregular longitudinal arranged short striae covering the entire test surface, giving the appearance of a matte and roughly textured wall under the light microscope. Outer wall layer consisting of longitudinally aligned plate shaped crystals. Aboral end rounded and slightly produced, oral end produced and connected with the peripheral margin of the preceeding chamber. Aperture basal, “Lachlanella”-type with a long slender tooth that becomes thickened at the tip.

Remarks. The species Triloculina? sp. 2 reported by Parker, 2009 from Western Australia differs from Triloculina kawea sp. nov. in its less triangular shape and less elongated outline. We consider Parker’s specimen a juvenile individual of Triloculina kawea. The aperture of Parker’s specimen is not intact but resembles very well the apertural features of Triloculina kawea. The outer wall layer appears identical (Fig. 5H). Parker mentioned the species to be possibly cryptoquinqueloculine. Figures 5B and 5F and the horizontal section (5D) show the triloculine chamber arrangement. Triloculina sp. 1, reported by Debenay 2012 from New Caledonia (p. 139, 278) is very similar in shape and surface ornamentation to Triloculina kawea, but has significantly more acute angles and a Y-shaped tooth. Triloculina kawea further differs from Triloculina linneiana d’Orbigny depicted by Baccaert, 1987 from the Great Barrier Reef (p. 128, pl. 57, Figs. 3 and 4) in the less striate ornamentation and more acute angles.

Subfamily Siphonapertinae Saidova, 1975

Etymology. In honor of Pamela Hallock Muller for her extensive work on tropical foraminifera.

Material. Four specimens from three samples (MS03, N18, W07; Fig. 1C; Table 1), recent.

Holotype. The specimen illustrated here as Figs. 6A–6C (sample MS03; MaLaPNG 2011–14).

Paratype. The specimen illustrated here as Figs. 6D–6F (sample N18; MaLaPNG 2011–14).

Type locality. The holotype is from sample station MS03 (18 m), a sand channel between Arborek Island and Pulau Mansuar. The paratype is from sample station N18 (30 m), south-west coast of Pulau Wayag; Raja Ampat, New Guinea (Indonesia).

Diagnosis. A medium-sized species of Siphonaperta Vella with a finely agglutinated wall, carinate shoulders, a short neck and a circular aperture with a small bifid tooth.

Description. Test porcelaneous and imperforate, medium-sized, about two times longer than broad, and ovate in outline. Outer layer of the calcareous test wall covered with finely agglutinated mostly biogenic grains. Agglutinated grains are particularly frequent along the sutures. Periphery carinate to subacute. Chamber arrangement quinqueloculine with five chambers visible from the exterior. Sutures slightly curved, incised and depressed. Chambers weakly inflated and angular in section, with weakly developed longitudinal striae (in well preserved specimens). Aboral end rounded and produced; oral end becoming more slender and leading into a short produced neck. Aperture terminal, a wide circular opening with a short T-shaped, bifid tooth, that reaches more than one third of the apertural diameter. Apertural opening surrounded by a slightly thickened and everted peristomal rim.

Dimensions. Observed range of test dimensions: test height 240–442 µm, test width 132–233 µm (lateral view), 87–119 µm (apertural view).

Occurence. Siphonaperta hallocki occurs sporadically in fine to coarse coral rubble samples from depths of 16 to 30 m.

Remarks. Very similar specimens were previously documented as Quinqueloculina sp. C from the Papuan Lagoon (Haig, 1988a) and Quinqueloculina sp. 13 from Ningaloo Reef (Parker, 2009). Test shape, wall texture and apertural features appear to be identical to our specimens from Raja Ampat. Quinqueloculina sp. 4 documented by Parker, 2009 from the Ningaloo Reef appears very similar to Siphonaperta hallocki, but differs in its more elongated shape, more rounded and inflated chambers and the cryptoquinqueloculine coiling. In addition, Parker describes the wall as roughly textured with some agglutinated grains. Quinqueloculina tropicalis Cushman from Samoa (1924, p. 63, pl. 23, Figs. 9 and 10) differs from our new species by its more compressed shape and more elongated broadly rounded chambers without any angles or costae. Quinqueloculina polygona D’Orbigny (1839, p. 198,pl. 12, Figs. 21–23) differs from Siphonaperta hallocki in its smooth and shiny surface, the pronounced carinae and the less inflated chambers. Langer et al., 2013 depicted a specimen of Quinqueloculina polygona d’Orbigny from Bazaruto (Langer et al., 2013, p. 163, Fig. 5: 14) that resembles our new species in size, shape and apertural features. However, it is unlikely that this species from Bazaruto belongs to Siphonaperta hallocki, as its outer wall layer is not agglutinated.