Epizoanthus karenae, Philipp, Nicholas A. & Fautin, Daphne G., 2009

Philipp, Nicholas A. & Fautin, Daphne G., 2009, Three new species of shallow water, yellow zoanthids (Hexacorallia: Zoanthidea: Epizoanthidae) from southern California, USA, and southern Australia, Zootaxa 2058, pp. 53-61 : 58-59

Epizoanthus karenae new species

Figures 1 C, 2B

Material examined. Pacific Ocean, Australia, South Australia, Gambier Group, Wedge Island, NE point, ~ 35° 09’S, 136° 28’E, 8–10 m, collected by K.L. Gowlett-Holmes, 20 March 2001; SAM H1602, Holotype, 24 polyps. Pacific Ocean, Australia, Tasmania, Tasman Peninsula, off O’Hara Bay, ~ 43° 05’S, 147° 48’E, 15–20 m, collected by K.L. Gowlett-Holmes and G. Myers, 31 July 1991; KUDIZ 0 0 2983, Paratype, 15 polyps.

Colony morphology and color. In life, vivid yellow with dark-orange lines radiating on oral disc ( Figure 1 C; Gowlett-Holmes 2008: p. 49, photo of “Undescribed species”). In preservative, dark-yellow/brown. Polyps close together, smaller ones surrounding larger ones. All protrude from surface of coenenchyme.

External anatomy. In preserved specimens, contracted polyps protrude no more than 12 mm from thin (1–2 mm thick) coenenchyme; 2–5 mm in diameter when contracted. Ectoderm and outer mesoglea densely encrusted with dark sand and quartz, contributing to brownish color. Scapus ridges obvious in closed polyps, number to 20 in small and large polyps.

Internal anatomy. Marginal sphincter muscle broad, alveoli not stratified and fill most of margin distally, transversely stratified and near endoderm proximally ( Figure 2 B). Mesenteries number to 36 in smaller polyp (2.5 mm diameter) to 40 in many larger polyps (5 mm diameter). Macrocnemes (20 in polyps with 40 mesenteries) equal number of scapus ridges. Actinopharynx longitudinally corrugated. Siphonoglyph apparent. No zooxanthellae.

Cnidae. Cnidom spirocysts, basitrichs, holotrichs, microbasic b- mastigophores, microbasic p - mastigophores ( Figure 3 ). See Table 3 for sizes and distribution.

Natural history, geography. Specimens studied were collected from a rock wall at 8– 20 m. Also known from New Zealand ( Gowlett-Holmes 2008).

Etymology. Epizoanthus karenae n. sp. is named after Karen L. Gowlett-Holmes in honor of her many contributions to knowledge of the Australian fauna, and the wonderful photographs she has taken of so many animals.

individuals examined having a particular type of nematocyst to the total number examined; n is the number of measured

capsules. Measurements, in µm, are given as a range of length x width; values in parentheses are of exceptionally large or

small capsules. Letters refer to images in Figure 3 .

E. karenae E. rodmani

Tissue Type N n Size N n Size

Tentacle: distal part spirocyst (F) 6/6 63 (13.3) 14.1–22.6 (23.8) x 6/6 64 12.6–22.6 x 2.3–4.3 2.3–4.3

basitrich (B) 6/6 51 16.4–28.5 x 2.3–5.7 3/6 23 15.7–19.3 (21.0) x 2.5–4.4 microbasic b - 6/6 64 (16.7) 17.8–28.6 (32.6) x 3/6 32 18.0–25.9 x 3.8–5.7 mastigophore (D) 3.1–5.5

Tentacle: proximal spirocyst (F) 6/6 60 14.5–23.3 x 2.0–4.3 6/6 63 13.2–22.7 x 2.2–4.0

part (5.6)

basitrich (B) 4/6 37 16.7–22.2 (24.4) x 4/6 41 (16.4) 17.7–22.1 (23.4) x 2.1–3.8 2.4–3.8 microbasic b - 6/6 60 16.5–30.4 x 3.0–5.2 5/6 45 (14.5) 16.9–23.6 x 3.3–5.6 mastigophore (D) (5.6)

Actinopharynx basitrich (B) 6/6 61 17.9–26.5 x 3.0–5.8 6/6 72 16.9–26.2 x 3.6–5.4

holotrich (G) 5/6 39 18.7–29.1 x 8.2–13.3 5/6 37 20.3–28.9 (30.4) x 9.8–18.5 holotrich (E) 4/6 36 9.0–13.3 x 3.0–5.5 5/6 52 (5.4) 7.0–12.7 x 2.8–4.3 microbasic p - 3/6 23 18.0–23.5 x 3.4–6.8 1/6 7 18.6–20.7 x 4.6–6.0 (8.1) mastigophore (C)

Filament holotrich (E) 6/6 57 8.9–14.5 x 3.1–5.8 6/6 60 8.0–13.6 (15.0) x 2.5–5.1 holotrich (G) 6/6 48 22.1–32.8 (36.0) x 6/6 44 19.3–31.3 x 10.0–16.2 9.7–16.2 (18.4)

microbasic b - 3/6 28 15.4–20.6 (23.0) x 3/6 21 15.7–21.2 (25.6) x 3.6–5.9 mastigophore (D) 3.6–5.3

microbasic p - 6/6 64 17.1–23.2 (25.1) x 6/6 59 (16.3) 18.1–22.2 (24.1) x mastigophore (C) 3.6–6.5 4.0–6.1

Figures

FIGURE 2. Longitudinal sections through alveolar marginal sphincter muscles of new species of Epizoanthus. A. Epizoanthus giveni n. sp. Alveoli nearly circular in cross section, arrayed in single column, separate from one another, decrease in diameter proximally. B. Epizoanthus karenae n. sp. Alveoli not stratified and fill most of margin distally, transversely stratified and near endoderm proximally. C. Epizoanthus rodmani n. sp. Alveoli elongate in cross section, located nearer ectoderm distally, near endoderm proximally. Scale bar = 200 µm.

FIGURE 3. Cnidae. Scale bar = 20 µm; refer to Tables 1 and 3 for occurrences and size ranges. A. Basitrich. B. Basitrich. C. Microbasic p - mastigophore. D. Microbasic b - mastigophore. E. Holotrich. F. Spirocyst. G. Holotrich.

FIGURE 1. A. Epizoanthus giveni n. sp. in life, attached to a rock wall. Note vivid yellow color and polyps of various sizes. Photograph by Daniel W. Gotshall, with permission. B. Epizoanthus scotinus in life. Note wider oral disc and paler column, tentacles, and oral disc as compared to E. giveni n. sp. Photograph by Daniel W. Gotshall, with permission. C. Epizoanthus karenae n. sp. in life. Note radiating dark-orange lines on oral disc. Photograph by Karen Gowlett-Holmes, with permission. D. Epizoanthus rodmani n. sp. in life. Note lack of radiating lines on oral disc. Photograph by Karen Gowlett-Holmes, with permission. Scale bars = 2 cm; scale was determined in consultation with the photographers.