Marphysa sinensis Monro, 1934

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 : 240-247

Marphysa sinensis Monro, 1934

Marphysa sinensis Monro, 1934 ; 367–369, Fig. 5 A–F. Figs 1 , 6 A–F, Table 3

Material examined. Lectotype: BMNH 1933.3 .2.16, Xiamen (Amoy), China, (118.04°E; 24.27°N) . Paralectotype: BMNH 1933.3.2.17.

Description. Two specimens both incomplete, Lectotype, with 105 chaetigers, 50 mm in length, maximum width at chaetiger 10, 2 mm, excluding parapodia, length from anterior to posterior margin of chaetiger 10, 5.95 mm. Gravid with coelom full of oocytes. Paralectotype with 54 chaetigers, 24 mm in length and maximum width at chaetiger 10, 1.5 mm, length from anterior to posterior margin of chaetiger 10, 5.00 mm. Preserved specimens colour beige, not iridescent.

Prostomium shorter than length of peristomium, margins of prostomium dorsally flattened with rounded margins, sulcus absent. Eyes absent. Antennae arranged all in straight line. Length of antennae varies, median longer and thicker than lateral ones, longest antennae reaching anterior margin of chaetiger 1 ( Fig. 6 A). Ceratophores smooth, ceratostyles tapering, articulated. Palps faintly articulated, shorter than antennae. Ratio of length between antennae and palps is 1.5x. Peristomial rings well demarcated all around ( Fig. 6 B). The posterior end of muscularised pharynx is at chaetiger 3. Mandibles with calcareous plates longer than sclerotized matrix. Maxillae I more than twice length of carrier; maxilla III arched with anterior teeth in line with posterior ones. Maxillary formula: I=1+1, II=7+7, III=7+0, IV=4+8, V=1+0 ( Fig. 6 E).

Parapodia vary along the body, anterior parapodia with chaetal lobe much shorter than postchaetal lobe, median with chaetal lobe shorter than postchaetal lobe, posterior with chaetal lobe same length as postchaetal lobe. Prechaetal lobe shorter throughout. Dorsal cirri longer than chaetal lobe, becoming long and thinner posteriorly. Ventral cirri globular throughout body, base of ventral cirrus inconspicuous. Ventral cirri always much shorter than dorsal cirri ( Fig. 6 C). Branchiae pectinate, begin from chaetiger 17, and continue to chaetiger 30 on one side and 31 on the other side. Number of branchial filaments up to 14 filaments, with maximum number of filaments, in anterior branchial segments. (Smaller specimen with branchial filaments from 17–29 on one side and 17–29 on the other side). Maximum length of branchial filaments up to 3x length of notopodial cirrus or longer ( Fig. 6 D). Parapodia 3, 28, 53, 78, 95, examined under the light microscope. Aciculae black with maximum number of 2, in median parapodia. Subacicular hooks brown, bidentate and hooded, present in median and posterior parapodia. Number of subacicular hooks range from 2–3 per parapodium and first appear from chaetiger 53. Compound spinigers present, throughout, number within a parapodium is 35 in anterior chaetigers. Compound falcigers present. Number of compound falcigers within a parapodia is 27 in anterior segments (mid and posterior parapodia with mainly damaged chaetae). Pectinate chaetae absent. Limbate capillaries present throughout body, all similar, number within a parapodium is 10 in anterior chaetigers ( Fig. 6 F).

Marphysa M. orientalis M. tamurai M. teretiuscula (= M. multipectinata n.sp. simplex )

Marphysa tribranchiata n.sp. Marphysa tripectinata n.sp Remarks. One of the two specimens is a mature female and Monro (1934) describes both in his description. To fix the identity of the species we designate the largest syntype of these as the lectotype (BMNH 1933.3.2.16) and the remaining one (BMNH 1933.3.2.17) as a paralectotype. A large number of parapodia have previously been removed and not retained. We made permanent mounts of chaetigers, 3, 28, 53, 78 and 95. While we have been able to make some comments on the chaetal structure, counts of numbers of types of chaetae are not possible as many of the chaetae have been broken. This species is very distinctive with the pectinate branchiae restricted to only 12 segments and lacking pectinate chaetae, but possessing both compound falcigers and spinigers. Monro (1934) in his description also indicated that no pectinate chaetae were present which is extremely unusual for this genus but we carefully checked and none can be seen, and perhaps they were just damaged. However, Monro (1934) does not make any comments about the chaetae being damaged. It appears that this species has only been reported by Wu (1962) and Wu (2013) since it was described, but with no additional comments given by either authors and it seems likely that they did not examine the material, although the limited number of branchiae and their structure is very distinctive.

Marphysa stragulum ( Grube, 1878) which was described from the Philippines has similar pectinate branchiae from chaetigers 13–21 with the maximum number of filaments as seven, but only has spinigers and no falcigers. We have not included this species in Table 3, as the original description is very brief and there is insufficient to include in the Table. It appears that the species has not been recorded since Grube, and no redescription of the type material deposited in Poland has been undertaken.

Habitat. Not given.

Locality. Xiamen (Amoy), China, (118.04°E; 24.27°N), see Fig. 1 .

Figures

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

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.

FIGURE 6. Marphysa sinensis. Lectotype (BMNH 1933.3.2.16). Light photographs A. Anterior end of lectotype, dorsal view. B. Anterior end of lectotype, lateral view. C. Right anterior parapodium of lectotype, lateral view. D. Branchiae at anteriormedian region of lectotype. E. Maxillary apparatus, dorsal view. F. Chaetae of lectotype, parapodium 3: (1). compound spiniger; (2). compound falciger; (3). simple capillaries. A – F. BMNH 1933.3.2.16 - 17. Scale bars: A, B, D = 1 mm. C, E = 0.5 mm. F = 0.1 mm.