Pherecardites monroi, Salazar-Vallejo & Piotrowski & Gustav & Paulay, 2025

Salazar-Vallejo, Sergio I., Piotrowski, Christina N., Gustav, Leslie Harris & Paulay, Gustav, 2025, Revision of Pherecardia Horst 1886 (Annelida Amphinomidae), Zoosystema 47 (28), pp. 691-720 : 714-715

Pherecardites monroi n. nom.

( Fig. 16)

urn:lsid:zoobank.org:act:

Pherecardia parva Monro, 1924: 73 ( non Pherecardites parva Horst, 1912 ).

DIAGNOSIS. — Pherecardites without patterned pigmentation. Median antenna almost as long as caruncle. Anterior eyes 2-3 times as large as posterior ones. Neurochaetae aciculars, subdistally denticulate, tips bent.

TYPE MATERIAL. — Holotype. China Sea , Macclesfield Bank • 1 specimen; no further data; NHML 1925.1 .28.144.

ETYMOLOGY. — The specific epithet is derived after the late Dr C. C. A. Monro, a taxonomist of polychaetes in the then British Museum of Natural History, London ( Baylis 1942), in recognition of his many faunistic publications and because he described the holotype used for the new combination.

DISTRIBUTION. — Only known from the Macclesfield Bank, China Sea, at unspecified depth or substrate (see Salazar-Vallejo 2020: 89 for notes on the HMS Alert Expedition and its specimens).

DESCRIPTION OF TYPE SPECIMEN

Holotype (NHML 1925.1.28.144) complete, delicate, almost broken into two parts; body roughly rectangular, tapered posteriorly, bent ventrally, pale. Right parapodia of chaetiger 20, notopodia of chaetigers 14-16, left parapodia of chaetigers 15, 20, 25-27, and notopodia of chaetigers 19 and 28 previously removed (lost), right parapodium of chaetiger 13 removed for observation.Body about 15 mm long, 3 mm wide, 41 chaetigers.

Prostomium oval, barely longer than wide ( Fig. 16A). Eyes black, anterior and posterior eyes laterally separated, anterior eyes 2-3 times as large as posterior ones ( Fig. 16B). Lateral antennae tapered, 1/4 as long as median antenna, palps as long as antennae, tapered. Median antenna cirriform, about as long as caruncle. Caruncle with six radiating smooth lobes, left ones removed. Mouth opening between chaetigers 2 and 3.

Parapodia with divergent notopodial and neuropodial lobes ( Fig. 16C). Dorsal and ventral cirri biarticulate; dorsal cirrophore and cirrostyles of similar length, both longer posteriorly; ventral cirrophore 1/4 to 1/5 as long as cirrostyle.

Branchiae arborescent from chaetiger 1 to posterior-most chaetiger; each with a single stem diverging into two branches, which are usually transversely aligned behind notopodia, and with about eight filaments in median chaetigers ( Fig. 16D); largest branchiae in chaetiger 2, progressively smaller posteriorly.

Chaetae damaged, presumably due to long preservation in formalin. Notochaetae including harpoon chaetae and thin smooth capillaries; neurochaetae including aciculars with multidentate tips ( Fig. 16E) and smooth capillaries.

Posterior end tapered; pygidium with anus terminal; anal plate fleshy, truncate.

REMARKS

Pherecardia parva Monro, 1924 was based on a single small specimen without pigment pattern. Chaetae were found to be similar to those present in P. striata . Monro (1924: 73) indicated that his new species differed from typical P. striata by lacking pigmentation, the position of the caruncle, the longer median antenna, and the larger size of branchial filaments. However, the specimen had been in preservative for some 40 years before he studied it, potentially impacting its pigmentation. The primary difference between these species regarding the caruncle is its general shape.

As indicated above, the lateral lobes of the caruncle in Pherecardites Horst, 1912 are roughly digitate and smooth, whereas in Pherecardia they are foliose, and rugose (pinnate)