Virchowia Langerhans 1879
- Dataset
- Revision of Autolytinae (Syllidae: Polychaeta).
- Rank
- GENUS
Classification
- kingdom
- Animalia
- phylum
- Annelida
- class
- Polychaeta
- order
- Phyllodocida
- family
- Syllidae
- genus
- Virchowia
description
Description. Length 8 – 15 mm for 47 – 70 chaetigers, width 1 – 1.5 mm. Preserved material yellowish, no colour markings. Ciliation not possible to assess. Eyes almost confluent (Fig. 31 G); eye spots present. Palps small, not projecting in front of prostomium (Fig. 31 G), fusion not assessed. Nuchal epaulettes on outgrowths, originating from backside of prostomium, reaching end of chaetiger 2; nuchal epaulettes branching, treelike (Fig. 31 A). Median antenna reaching chaetiger 5 – 6. Lateral antennae and dorsal tentacular cirri, length 1 / 2 – 2 / 3 of median antenna. Ventral tentacular cirri 1 / 2 as long as dorsal pair. First dorsal cirri c. 3 / 4 as long as median antenna, second dorsal cirri as long as ventral tentacular cirri. From chaetiger 1 – 27 cirri with usual alternation in direction, followed by 3 DDUUgroups and 1 DDUgroup (n = 1), more posterior difficult to assess. Dorsal cirri from chaetiger 3, alternate in length; short cirri equals 1 / 3 – 1 / 2 of body width, long cirri equals 1 – 1.5 times body width; cirri with distinct alternation in placement, long cirri inserted dorsal to short cirri (Fig. 31 C). Cirrophores present on tentacular cirri, and all dorsal cirri. Cirrophores and cirrostyles unequal; cirrophores and cirrostyles on short cirri c. 1 / 3 in length of its counterpart in long cirri (Fig. 31 C); cirrophores on short cirri with thin base, cirrophores on long cirri with broad base; cirrophores shorter than parapodial lobes; cirrophores shorter than cirrostyles. All appendages more or less clavate (Fig. 31 A, C, D), long cirri more distinctly so. Parapodial lobes conical, small. Anterior chaetigers with 1 – 2 aciculae, 1 in median and posterior. Chaetal fascicle with c. 20 compounds in anterior chaetigers, 5 – 15 in median and posterior. Compound chaetae with small distal tooth; serration present (Fig. 31 E). Single thick bayonet chaetae, distally dilated (Fig. 31 F), present in posterior chaetigers. Pharynx with single to multiple sinuations anterior and lateral to anterior half of proventricle. Trepan in chaetiger 2, not possible to evaluate detail structure. Proventricle equal in length to 2 – 3 segments in chaetiger 6 – 8 with c. 50 rows of muscle cells (n = 2). Anal cirri equal in length to short cirri. Reproduction. Schizogamy by anterior scissiparity behind chaetiger 13. The holotype as well as one of the nontype specimens with developing heads, with 3 small antennae (Fig. 31 B), behind chaetiger 13. Morphology of epitokous stages. Unknown. Additional information. The trepan is described by Avernicev (1972); it has 20 unequal teeth, 1 large alternating with 1 – 3 smaller. Habitat. Rocky bottom, 25 – 40 m.
description
Male. See descriptions under V. clavata, V. japonica Imajima & Hartman, 1964, and V. pectinans. Female. See description under V. c l a v a t a.
diagnosis
Diagnosis. Virchowia with nuchal epaulettes as branching outgrowths.
discussion
Remarks. Virchowia branchiata is the only autolytine that has nuchal epaulettes as furcating outgrowths; it is thus very easily identified. There is no doubt that Ehlers' second description and Augener's redescription of Phyllosyllis albida are of V. branchiata. However, Ehlers' original description of P. albida is not the same as V. branchiata. See also remarks for P. albida nomen dubium.
distribution
Distribution. Antarctic, Davis Sea.
materials_examined
Material examined. Antarctic Sea: holotype, ZIL 15766, and 2 paratypes, ZIL 15767, Davis Sea, Tokarev, 30 m, rocks, 12 Jan 1966; 5 spms, ZIL 42046 – 42050, Davis Sea, 1971.
Name
- Homonyms
- Virchowia Langerhans 1879
- Virchowia