Clavigofera pacifica Harris & Iwasaki, 1996

Harris, Vernon A., 2014, Porcellidiidae of Australia (Harpacticoida, Copepoda). II. The Importance of the Male Antennule in Taxonomy, Records of the Australian Museum 66 (2), pp. 111-166 : 156-161

publication ID	https://doi.org/ 10.3853/j.2201-4349.66.2014.1595
persistent identifier	https://treatment.plazi.org/id/03E56619-FFFD-322E-F544-7E5F53B64B97
treatment provided by	Carolina
scientific name	Clavigofera pacifica Harris & Iwasaki, 1996
status

Treatment

Figs 30–33 View Figure 30 View Figure 31 View Figure 32 View Figure 33

Clavigofera pacifica Harris & Iwasaki, 1996: 201 , 204, figs. 1, 2.— Bodin, 1997: 67; Wells, 2007: 80.

Type material. Type locality: Kadonohama Bay , Ofunato, Iwate Prefecture, Japan. Holotype (female) NSMT-Cr 11950, allotype NSMT-Cr 11951 deposited in the National Museum of Natural Sciences, Tokyo, Japan.

Australian specimens from NSW deposited at the AM, Sydney, P89053, 20 ♀♀, 10 ♂♂, 8 ♂♂ coupled with juvenile female ex Lobophora variegata, Shelly Beach, Cronulla, Sydney , 34°03' S 151°11' E) V. A. Harris, 1974. Australian specimens deposited at NHM, London .

Diagnosis. Ventral surface of cephalosome with wrinkles parallel to edge, hyaline border with striations parallel to edge; lateral striations on female genital double-somite 10% of animal’s length; Hicks index for α on female caudal ramus = 52%; α and β setae on male caudal ramus short (1/3 length of ramus); δ seta on segment 3 of male antennule about same length as segment 2; setules absent from anterior lobe of mandible; antenna endopod segment 2 without extensive area of setules; no row of setules on lateral surface of maxilliped basis.

Biometric data. Data for Australian specimens, (values for Japanese specimens within square brackets).

Females (N = 29 [27]): maximum length (Lmax) mean 0.59 mm [0.61 mm], body length (Lurs) mean 0.57 mm [0.58], range 0.53–0.58 mm; cephalosome width (W) mean 0.35 mm [0.39 mm]; rostrum width (R) 0.060 mm [0.065 mm]; genital double-somite width 0.22 mm; caudal ramus length 0.16 mm, width (max) 0.065 mm.

Ratios: (Lmax)/ W 1.65, (Lurs)/ W 1.52; caudal ramus l/ w 2.4 [2.2], Hicks index for α 52% [52%]; number of eggs carried by female 6 [6].

Males (N = 14 [16]): maximum length (Lmax) mean 0.44 mm [0.42 mm], range 0.40–0.47 mm, body length (Lurs) mean 0.39 mm [0.38 mm]; cephalosome width (W) mean 0.32 mm [0.31 mm]; antennule length (N = 6) 0.123 mm; spermatophore length 0.08 mm.

Ratios: (Lurs)/ W 1.22; antennule 28% of (Lurs) [measurements of male antennule segments made on two paratype specimen from Japan fall within the range of animals from Australia], segment 2 37%, segment 3+4 36%, dactylus 17%, aesthetasc 68% of antennule length, δ seta = length of segment 2, spermatophore 21% of ( Lurs ) .

Description. Adult females ( Fig. 30A View Figure 30 ): colour pale yellow or colourless. Anterior of cephalosome slightly truncated, rostrum very narrow (18% of cephalosome width). Sides of body outline almost parallel. Hyaline border with striations parallel to edge ( Fig. 30G View Figure 30 ), 10 µm wide, dorsal pits conspicuous, 5–6 µm. Ventral surface of cephalosome with wrinkled cuticle parallel to border ( Fig. 31C View Figure 31 ). Lateral band of striations (striated rugose band) on ventral surface of genital double-somite anterior lobe 33% of somite length, dorsal surface of genital double-somite pitted. Notch and broad scar indicate boundary between anterior and posterior lobes ( Fig. 30B View Figure 30 ), posterior lobe narrow, straight sided, acutely pointed posteriorly, bordered with fine setules. Posterior arch deep, encloses almost 3/4 of caudal furca. Sternal sclerite of metasome segment 4 fimbriate on posterior edge ( Fig. 31D View Figure 31 ). Caudal rami rectangular, widen posteriorly ( Fig. 30F View Figure 30 ), posterior border slightly convex with terminal fringe of setules. Terminal setae T1–T4 large, pinnately clavate ( Fig. 30C View Figure 30 ), evenly spaced along posterior edge [terminal setae of copepodids are not pinnate clavate], α seta about half way down ramus. Structure and setation of mouthparts and ambulatory limbs typical of family. Segment 2 of antenna endopod with a few surface setules, no extensive rows of setules ( Fig. 31B View Figure 31 ). Mandibular palp without setules on anterior lobe. Maxillule with single bulbous seta on exopod. Seta on distal endite of maxilla plain, not comb-like ( Fig. 31A View Figure 31 ). Maxilliped without lateral row of surface setules on basis ( Fig. 31E View Figure 31 ). Very small patch of denticles at lateral end of fimbriate crescent on P1 endopod ( Fig. 32F View Figure 32 ). Serrulate spinous terminal seta on P2 endopod 3/4 length of endopod ( Fig. 31A View Figure 31 ). Serrulate spinous seta on segment 2 of P3 endopod shorter than endopod (0.85:1), large serrate spinous seta on segment 3 of endopod much longer than endopod (1.5:1) ( Fig. 32C View Figure 32 ). Seta on segment 2 of P4 endopod and first internal seta on segment 3 finely serrulate, spinous ( Fig. 32B View Figure 32 ). Exopod of P5 lanceolate, dorsal surface pitted, one dorsal seta plus subapical and smaller apical seta ( Fig. 30E View Figure 30 ), apex of P5s reach beyond posterior extremity of genital double-somite but do not touch one another. Females carry six eggs.

Adult males ( Fig. 30D View Figure 30 ). Colour, hyaline border, dorsal pits and wrinkled ventral edge of cephalosome as described for female. Cephalosome truncated, anterior edge turned ventrally, lateral angle of antennule socket prominent, shoulders sharply rounded ( Fig. 33A View Figure 33 ). Caudal rami quadrate (l/w = 1) with lateral edge convex, dorsal surface pitted, α and β setae short (less than half length of ramus), terminal setae T1–T4 pinnately clavate, equal in size and equally spaced ( Fig. 33B View Figure 33 ). Limbs as for female except for the following. Antennule held in characteristic posture when not folded ventrally ( Figs 30D View Figure 30 , 33F View Figure 33 ), segment 2 as long as segment 4 + dactylus, segment 3 with very short ventral process, δ seta short (= length of segment 2), aesthetasc nearly twice length of segment 2, coupling denticles on segment 4 very small, proximal pointed, distal rounded, dactylus short with segments 5 and 6 distinct (1/2 length of segment 2) ( Figs 33E, F, G View Figure 33 ). Endopod of P2 with two plumose and one serrulate spinous seta on segment 3 ( Fig. 32D View Figure 32 ). Spermatophore about 1/5 length of animal.

Remarks. Detailed descriptions of Clavigofera clavigera , C. laurencia and C. ulva that would confirm their validity were not given. A full description of these species is needed to justify use of Hicks’ index to separate them.

Stage IV and V male and female copepodides have slender pinnate terminal setae on their caudal rami ( Figs 32E View Figure 32 , 33C View Figure 33 ). The characteristic pinnately clavate terminal setae of adults appear at metamorphosis.

Distribution. Clavigofera pacifica is widely distributed on the coasts of Japan.Australian specimens have been collected from the mid and northern coast of NSW.

The species has been recorded as abundant on Lobophora variegata at the following localities: Broulee rock platform (35°52'S 150°71'E) 47 ♀♀, 22 ♂♂, 6 coupled ♂♂; Shelly Beach, Cronulla, Sydney (34°03' S 151°11' E) 103 ♀♀, 85 ♂♂, 41 coupled ♂♂; Arrawarra Headland (30°03' S 155°02' E) 122 ♀♀, 70 ♂♂, 74 coupled ♂♂, V. A. Harris 1974, 1976, 1982. The species has been collected from a number of other seaweeds in smaller numbers. On Caulerpa sp., at Broulee, and Ballina (28°52'S, 153°36'E) also on Gelidium sp., at Nambucca Heads (30°39' S 153°01' E) V. A. Harris 1982.