Marphysa multipectinata, Liu, Yubin, Hutchings, Pat & Sun, Shichun, 2017

Liu, Yubin, Hutchings, Pat & Sun, Shichun, 2017, Three new species of Marphysa Quatrefages, 1865 (Polychaeta: Eunicida: Eunicidae) from the south coast of China and redescription of Marphysa sinensis Monro, 1934, Zootaxa 4263 (2), pp. 228-250 : 234-236

Marphysa multipectinata n. sp.

Figures 1 , 3 , 4 H, 5D–F, Tables 2, 3

Material examined. Holotype: ASIZW0000345-1 collected by Shi-Kuei Wu from Shimen, 0 8.08.1964, (121.56°E; 25.3°N), selected parapodia mounted for SEM (parapodia 3, 60, 130, 190, 250 and 290). Paratypes: ASIZW0000345-2, width at chaetiger 10, 4.05 mm, length from anterior to posterior margin of chaetiger 10, 12.55 mm, complete with 215 chaetigers collected by Shi-Kuei Wu from Shimen, 0 8.08.1964, (121.56°E; 25.3°N); ASIZW0000353-1, width at chaetiger 10, 4.9 mm, length from anterior to posterior margin of chaetiger 10, 13.3 mm, complete with 401 chaetigers.

Additional material examined. ASIZW0000353-2, width at chaetiger 10, 4.6 mm, length from anterior to posterior margin of chaetiger 10, 15.25 mm, complete with 377 chaetigers collected by Shi-Kuei Wu, (no locality data or date of collection given), plus the following incomplete specimens, ASIZW0000343, collected by Shi-Kuei Wu from Keng-Liaw, 12.05.1966, (121.56°E; 25.3°N); ASIZW0000344-1, ASIZW0000344-2 collected by Shi- Kuei Wu from Yi-Lan, 0 9.15.1964, (121.79°E; 24.47°N); ASIZW0000345-3 collected by Shi-Kuei Wu from Shimen, 0 8.08.1964 (121.56°E; 25.3°N), ASIZW 0000347-2 collected by Shi-Kuei Wu from Shimen, 0 6.08.1965 (121.56°E; 25.3°N). All material collected from Taiwan of China.

Description. Holotype complete, with 304 chaetigers. Body iridescent. Preserved specimen colour red or dark pink. Maximum width at chaetiger 10, 5.7 mm, excluding parapodia. Length from anterior to posterior margin of chaetiger 10, 13.9 mm.

Prostomium shorter than length of peristomium, margins of prostomium dorsally flattened with conspicuous deep median sulcus. Eyes present, black, behind the palps (lateral to lateral antennae. Median antenna inserted slightly more posterior to lateral ones. Length of antennae varies, median longer and thicker than lateral ones, longest antennae reaching to median or posterior margin of the second peristomial ring. Ceratophores smooth, ceratostyles digitiform with surface wrinkles. Palps smooth, shorter than antennae. Ratio of length between antennae and palps 1.2x ( Fig. 3 A). Peristomial rings well demarcated all around. Mandibles with calcareous plates longer than sclerotized matrix ( Fig. 3 D). Maxillae I more than twice length of carrier; III arched with anterior teeth in line with posterior ones. Maxillary formula: I=1+1, II=3+3, III=4+0, IV=4+5, V=1+1 ( Fig. 3 E).

Parapodia vary along the body, anterior parapodia with prechaetal lobe poorly developed, shorter than chaetal lobe which is similar in size to postchaetal lobe, median parapodia with prechaetal lobe poorly developed and postchaetal lobe larger than chaetal lobe. Posterior parapodia with poorly developed prechaetal lobe, and chaetal and postchaetal lobes almost same length. Dorsal cirri tapering, all similar and same length as chaetal lobes. Ventral cirri digitiform throughout body, base of ventral cirri inconspicuous. Length similar throughout body. Dorsal cirri slightly longer than ventral cirri in the anterior body and posterior body, whereas in median parapodia appear similar in length. Branchiae palmate, begin from chaetiger 32 and end at chaetiger 281. Anterior branchiae with 1– 2 simple filaments, with maximum number of branchial filaments reaching 5, in median parapodia ( Fig. 3 B–C). Length of branchial filaments where best developed up to 2–2.5x length of dorsal cirri. Parapodia 3, 20, 70, 120, 170, 220, 270, examined under the light microscope. Aciculae, brown, with maximum number 5 in anterior region ( Fig. 3 G). Subacicular hooks present, yellow, uni- and bidentate, present throughout from chaetiger 20 ( Fig. 5 D). Maximum number of subacular hooks is 2 per parapodia. Compound spinigers present, throughout. Number of compound spinigers within a parapodia is 13–27. Compound falcigers absent. Pectinate chaetae present, restricted to median and posterior segments commencing from about chaetiger 70. Number of pectinate chaetae within a parapodia is 14–22. Pectinate chaetae consist of 4 types ( Table 2), with both asymmetrical and symmetrical teeth, outer teeth diverse, in some chaetigers, outer teeth are longer than inner teeth ( Fig. 3 G, Fig. 5 E–F). In median parapodia, only symmetrical isodont pectinate chaetae present with about 16 teeth ( Fig. 4 H–I). In posterior parapodia all 4 types present: symmetrical isodont pectinate chaetae with about 14–16 teeth ( Fig. 3 G-(III), Fig. 4 H- III); asymmetrical anodont pectinate chaetae with parallel 12 teeth ( Fig. 3 G-(II), Fig. 4 H-V); asymmetrical isodont pectinate chaetae with 12–16 teeth ( Fig. 3 G-(1), Fig. 4 H-VI); asymmetrical anodont pectinate chaetae with about 4 teeth ( Fig. 4 H-IV, Fig. 3 G-(IV)).

Limbate capillaries present, present throughout body, all similar, with the number per parapodia 10–19.

Pygidium with 2 pairs of pygidial cirri ( Fig. 3 F), one pair longer than the other, shortest pair located ventrally, and longest inserted posterior laterally.

Variation. The paratypes exhibit the following variation, branchiae starting from chaetigers 29 to 32, and with 20–31 of the posterior-most chaetigers without any branchiae, with maximum number of filaments 3–5. The ratio of the length between the antennae and the palps varies between 1.2 to 1.4.

Remarks. Marphysa multipectinata is described as a new species, characterised by four types of pectinate chaetae within a single parapodium, differing in the number and arrangement of teeth and first present from about chaetiger 70. The number of pectinate chaetae present, about 18–22 per parapodium is similar to M. tribranchiata n. sp. but far greater than all the other species of this group of Marphysa (see Table 3). The only exception is M. tribranchiata n. sp. but this differs from M. multipectinata n. sp. in only having two types of pectinate chaetae, symmetrical isodont and anodont. Both M. multipectinata n. sp. and M. tribranchiata n. sp. co-exist at several locations in Taiwan, and which can be easily separated by the presence or absence of eyes, which are present in M. multipectinata n. sp. and absent in M. tribranchiata n. sp. Zanol et al. (2016) also found some Australian species of Marphysa co-occuring at the same sites.

Etymology. The specific name multipectinata refers to the presence of four types and large numbers of pectinate chaetae.

Habitat. Not recorded.

Type locality. Shimen, Taiwan of China, (121.56°E; 25.3°N), see Fig. 1 .

Distribution. Yi-Lan and Keng-Liaw, Taiwan of China.

Figures

FIGURE 1. Type localities of Marphysa tripectinata n. sp., M. multipectinata n. sp., M. tribranchiata n. sp. and M. sinensis.

FIGURE 3. Marphysa multipectinata n. sp. Light photographs of A. Anterior end of holotype, dorsal view. B. Branchiae at median region of holotype. C. Right median parapodium of holotype, lateral view. D. Mandible, ventral view. E. Maxillary apparatus, dorsal view. F. Pygidium of holotype, ventral view. G. 4 types of pectinate chaetae of holotype, parapodium 270: (I) asymmetrical isodont pectinate chaetae with 12 – 16 teeth; (II) asymmetrical anodont pectinate chaetae with 12 parallel teeth; (III) symmetrical isodont pectinate chaetae with about 14 – 16 teeth; (IV) asymmetrical anodont pectinate chaetae with about 4 teeth. A, B, C, F, G. ASIZW 0000345 - 1. D, E. ASIZW 0000345 - 2. Scale bars: A, B = 2 mm. C = 0.5 mm. D, E, F = 1 mm. G. = 0.1 mm.

FIGURE 4. Marphysa tribranchiata n. sp. and pectinate chaetae variation present in the three new species. Light photographs A. Anterior end of holotype, dorsal view. B. Branchiae at median region of holotype. C. Right median parapodium of holotype, lateral view. D. Mandible, ventral view. E. Maxillary apparatus, dorsal view. F. Pygidium of holotype, lateral view. G. 2 types of pectinate chaetae of holotype, parapodium 195: (I) symmetrical anodont pectinate chaetae with about 14 teeth; (II) symmetrical isodont pectinate chaetae with about 17 teeth. H. Schematic drawings of pectinate chaetae present in posterior parapodia of three new species. I. symmetrical anodont with parallel 12 teeth; II. symmetrical isodont with 8 – 12 teeth; III. symmetrical isodont with about 14 – 16 teeth; IV. asymmetrical anodont with about 4 teeth; V. asymmetrical anodont with about 14 teeth; VI. asymmetrical anodont with about 17 teeth; VII. asymmetrical anodont with 14 – 18 teeth; VIII. asymmetrical anodont with 5 – 7 teeth; IX. asymmetrical isodont with more than 30 teeth. A, B, C, F, G. ASIZW 0000348 - 2. D, E. ASIZW 0000348 - 3. H. ASIZW 0000348 - 2, ASIZW 0000345 - 1, AM W. 49069. Scale bars: A, B. = 2 mm. C = 0.5 mm. D, E, F = 1 mm. G = 0.2 mm. H = is not to scale.

FIGURE 5. SEM images of Marphysa tripectinata n. sp. and Marphysa multipectinata n. sp. Marphysa tripectinata n. sp. A. Compound spinigers chaetae, left parapodium 70. B. Symmetrical isodont pectinate chaeta, left parapodium 137. C. Two symmetrical anodont pectinate chaetae with parallel edge, left parapodium 204. Marphysa multipectinata n. sp. D. Subacicular hook and compound spinigers chaetae, holotype, left parapodium 3. E. Two symmetrical isodont pectinate chaetae holotype, left parapodium 130. F. Symmetrical isodont pectinate chaeta with few coarse teeth, holotype, left parapodium 250. A – C AM W. 49073. D – F ASIZW 0000345 - 1. Scale bars: A, D = 50 µm. B = 5 µm. C, E, F = 10 µm.