Cribrilaria harmeri Ristedt, 1985

Cribrilaria harmeri Ristedt, 1985

Figure 18 View FIGURE 18

v. 1985 Cribrilaria harmeri Ristedt , p. 26, figs. 1, 6–9.

v. 1988 Cribrilaria harmeri Ristedt ; Hayward, p.

290, pl. 3c.

v. 2006 Puellina harmeri (Ristedt) ; Dick, Tilbrook and Mawatari, p. 2213, fig. 6A, C, E, G.

v. 2017 Puellina harmeri (Ristedt) ; Dick and Grischenko, p. 170, fig. 9.

v. 2018 Puellina harmeri (Ristedt) ; Yang, Seo and Gordon, p. 229, figs. 36–38.

Figured material. PMC EDM-Collection J.H.B.129a, sample 19069 ( Figure 18A–B View FIGURE 18 ), sample 19019 ( Figure 18C–E View FIGURE 18 ), sample 19072 ( Figure 18F View FIGURE 18 ), and sample 19113 ( Figure 18G–I View FIGURE 18 ); Core 19, Daidokutsu cave, Okinawa, Japan, Holocene.

Description. Colony encrusting, multiserial, unilaminar. Autozooids distinct, separated by shallow grooves, oval to rounded polygonal, longer than wide (mean ZL/ZW 1.31). Frontal shield flat to slightly convex, consisting of 14–18 (mean 16) costae, including suboral pair, maximum basal width 23–48 µm, narrowing towards the centre, meeting along a straight or curved midline, with opposing tips either touching or alternating; pelmatidium inconspicuous, 2–5 µm in diameter. Costae connected by intercostal bridges creating 5–10 slit-like to reniform intercostal lacunae, 8–16 µm in length. Suboral pair of coastal number forming a small umbo in the midline, either leaving a conspicuous, rounded to heart-shaped suboral pore, measuring 10–24 µm in diameter, or a tiny suture, possibly related to ontogenesis. Gymnocyst smooth, exposed along zooidal margins, typically wider proximally. Orifice semicircular, almost as long as wide, with straight proximal margin; seven, evenly spaced oral spine bases, 10–20 µm in diameter, with the proximalmost pair placed slightly above the proximal oral margin; four spines in ovicellate zooids (three observed in one instance). Avicularia both interzooidal and adventitious. Interzooidal avicularia emerging from distolateral pore-chamber windows, resting on the substrate atop a small, bulbous cystid of smooth gymnocyst; rostrum smooth, long, slender, needle-like, resting on the frontal costate shield of distal zooid. Adventitious avicularia small, placed on the latero-oral gymnocyst without touching the substrate, usually paired, associated with ovicells; rostrum short, acutely triangular, directed distally or distolaterally outwards. Both types of avicularia with small mandibular pivots and finely denticulate rostrum. Ovicells of types A (produced by a distal autozooid; Figure 18D View FIGURE 18 ) and B (produced by a distal kenozooid; Figure 18C, F View FIGURE 18 ) as defined by Bishop and Househam (1987), and type 1 of Ostrovsky (2013); ooecium smooth with central ridge, reflecting the continuation of the costa from the distal zooid or kenozooid into the ooecium, and a small central umbo; distal portion of kenozooid almost always visible. Kenozooids elliptical to rounded polygonal, with costate shield of 13–16 radial costae. Pore-chamber windows seen along lateral walls of zooids at colony periphery, rounded to elliptical, 20–37 µm long by 6–17 µm wide.

Measurements (µm). ZL 416±41, 322–487 (4, 20); ZW 318±46, 212–417 (4, 20); GymL 71±27, 33– 142 (4, 20); OL 76±5, 65–83 (4, 20); OW 75±4, 65– 81 (4, 20); AvL (adventitious) 106±18, 83–142 (3, 10); AvW (adventitious) 46±4, 42–53 (3, 10); AvL (interzooidal) 206±10, 197–217 (2, 3); AvW (interzooidal) 50±2, 49–53 (2, 3); OvL 147±20, 119–183 (3, 10); OvW 184±24, 139–215 (3, 10); KzL 305±53, 215–344 (3, 5); KzW 247±42, 198–291 (3, 5).

Remarks. Cribrilaria harmeri has been recorded widely from localities including the Philippines (Ristedt, 1985), Mauritius (Hayward, 1988), Hawaii (Dick et al., 2006), Jeju Island in South Korea ( Yang et al., 2018), and Okinawa (Dick and Grischenko, 2017). This species shows considerable intraspecific and intracolonial variability, particularly in the denticulation of the avicularian rostra, which can range from smooth to finely denticulate or markedly serrated. Variability is also observed in the formation of the ovicells. Ooecia can be derived from either the distal autozooid or kenozooid. The development of the kenozooid associated with the ooecium can also vary. Some are well developed and visible in frontal view, with as many as ten costae, while others are less developed, with the frontal part not visible. An additional variation observed in the present specimens is in the number of intercostal lacunae, which are more numerous in the Japanese material than in previous descriptions.

This species stands out by having both interzooidal and adventitious avicularia. This characteristic complicates the task of assigning it to a specific genus, particularly because one of the primary distinctions between Cribrilaria and Glabrilaria is the type of avicularia they possess ( Rosso et al., 2018b). Canu and Bassler (1929) first established Cribrilaria as a genus. However, Bishop and Househam (1987) later reclassified it as a subgenus of Puellina , while introducing a second subgenus, Glabrilaria , for species with pedunculate avicularia. Rosso et al. (2018b) subsequently elevated all three taxa— Cribrilaria , Glabrilaria , and Puellina —to genus level. This taxonomic shift awaits validation through molecular sequence analysis. The presence of a species like C. harmeri , which features both types of avicularia, questions the legitimacy of the distinction between Cribrilaria and Glabrilaria . However, we prefer to keep the species in Cribrilaria because if future molecular studies suggest merging the two genera, Cribrilaria would have priority over Glabrilaria as it was established earlier.