Virchowia clavata Langerhans, 1879

Nygren, Arne, 2004, Revision of Autolytinae (Syllidae: Polychaeta)., Zootaxa 680, pp. 1-314 : 81-88

Virchowia clavata Langerhans, 1879 (Fig. 32A–E)

Virchowia clavata Langerhans, 1879: 582 –583, fig. 31A–F; 1884: 250; Fauvel 1923: 324 –325, fig. 125A–I; Okada 1937: 469 –470, fig. 20A, B; Cognetti 1957: 75; 1961: 305; San Martín 2003: 463 –466, figs 253A–C, 254A–I; Nygren & Sundberg 2003: GenBank sequences, 16S rDNA partial sequence AF474268 , and 18S rDNA partial sequence AF474314 .

Material examined. Madeira: 2 syntypes on slides NHMW 2604, Atlantic. France: 3 spms (1 mounted for SEM, 1 rear end in author's collection for DNA analyses), Banyulssur­Mer, 42°28.9'N 03°08.2'E, dive, 10 m, sponges, hydroids, May 1997.

Diagnosis. Virchowia with long sinuated pharynx; compound chaetae with well­developed serration.

Description. Length 3.6–4 mm for 28–35 chaetigers, width 0.15–0.20 mm. Live specimens yellowish­white with white conspicuous glands on antennae and dorsal cirri, and with a black spot in the segment borders; eyes red. Preserved specimens with white glands retained. Ciliation on nuchal epaulettes, and as one broad longitudinal band ventrally.

Eyes separated; eye spots present. Palps small, not projecting in front of prostomium, fused basally. Nuchal epaulettes on outgrowths (Fig. 32B), originating from backside of prostomium, reaching chaetiger 2–3.

Median antenna reaching chaetiger 3–4. Lateral antennae and dorsal tentacular cirri, length 1/2–2/3 of median antenna. Ventral tentacular cirri 1/3 as long as dorsal pair. First dorsal cirri 1/2 as long as median antenna, second dorsal cirri equal in length to short dorsal cirri. From chaetiger 1–27 cirri with usual alternation in direction, more posterior not assessed. Dorsal cirri from chaetiger 3, alternate in length; short cirri equals 2/3 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. 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; 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 clavate (Fig. 32A, B).

Parapodial lobes small, rounded. Single acicula present in all chaetigers. Chaetal fascicle with 5–8 compounds in all chaetigers. Compound chaetae with 2 small teeth (Fig. 32E), distal tooth somewhat smaller; serration present, well­developed. Single thick bayonet chaetae, distally dilated (Fig. 32E), beginning at chaetiger 1.

Pharynx with multiple sinuations anterior and lateral to anterior half of proventricle (Fig. 32C). Trepan in chaetiger 2 (Fig. 32C), with c. 24 equal teeth. Basal ring present; infradental spines present (Fig. 32D). Proventricle equal in length to 1 segment (Fig. 32C) in chaetiger 5 with c. 20 rows of muscle cells. Anal cirri equal in length to short cirri.

Reproduction. Schizogamy by anterior scissiparity behind chaetiger 13. Specimens with stolons found in January, February, September ( Cognetti 1957), and May (pers. obs.).

Morphology of epitokous stages.

Male. No mature stolons examined. Langerhans (1879), Okada (1937), and Gidholm (1967), present some information on morphology. Length c. 1.7 mm for 6+17+6 chaetigers ( Okada 1937; Gidholm 1967). Nuchal epaulettes on outgrowths. One pair of tentacular cirri, achaetous knobs absent, as judged from figures ( Langerhans 1879; Okada 1937) (uncertain observations). Cirri on chaetiger 2, 4, 6, and on every second chaetiger longer.

Female. No mature stolons examined. Langerhans (1879), and Gidholm (1967) give brief information on morphology. 6+14+5 chaetigers. Tentacular cirri 2 pairs, achaetous knobs absent, as judged from figure ( Langerhans 1879) (uncertain observation). Cirri alternate in length, at least in anterior region.

Habitat. Sponges, hydroids, 10m.

Distribution. North East Atlantic, Mediterranean.

Remarks. Virchowia clavata is almost identical to V. longipharyngea ; the former species has eye spots in front of the anterior pair of eyes not seen in V. longipharyngea and the pharynx also seems to be longer in V. longipharyngea . The compound chaetae in V. c l a v ­ ata, and V. longipharyngea with 2 small teeth, and with long serration, is also found in V. japonica , only known as a male stolon. This type of compound chaetae is unique for these three taxa, indicating a close relationship. The name Umbellisyllis is sometimes erroneously used instead of Virchowia (e.g. Hartman 1959; Fauchald 1977a; San Martín & Alós 1989; López & San Martín 1997). See remarks for Umbellisyllis in "Not Autolytinae­section".

Virchowia japonica ( Imajima & Hartman, 1964) comb. n. (Fig. 33A–D)

Autosyllis japonica Imajima & Hartman, 1964: 103 –105, pl. 22, fig. D–H; Imajima 1966: 82 –83.

Material examined. Japan: holotype LACM POLY­ 0155, off Shirikishinai, surface, plankton net, Oct 1958.

Diagnosis. Male stolon of Virchowia ­ type with triangular prechaetal lamellae in region b.

Description. Male type complete, length 3.4 mm for 6+13+12 chaetigers, width 0.35 mm in region a, 0.80 in region b. Preserved material whitish, without colour markings. Ciliation not assessed.

Prostomium with straight anterior margin. Four eyes, with lenses; eyes situated on ventral and dorsal side of prostomium, ventral pair larger (Fig. 33A, B). Palps absent. Nuchal epaulettes present as 2 short outgrowths (Fig. 33A), originating just lateral and posterior to median antenna.

Median antenna reaching chaetiger 7–8, c. 1/4 of body length. Lateral bifid antennae, as long as or slightly longer than prostomial width; basal part 1/2 of total length, inner dorsal rami longer and stouter than outer ventral. Frontal processes, equal to 1/4 of prostomial width. Tentacular cirri 2 pairs; dorsal pair as long as 1/2 prostomial width, ventral tentacular cirri 1/2 as long as dorsal pair (Fig. 33B). First dorsal cirri, equal in length to median antenna; achaetous knobs absent (Fig. 33B). Second dorsal cirri situated above first chaetigerous lobe (Fig. 33B). Cirri from chaetiger 1 alternate in direction in region a, and b, with regular DU­group (Fig. 33A); thus cirri on chaetiger 1, 3, 5 and so forth pointing down, and cirri on chaetiger 2, 4, 6 and so forth pointing up. Cirri in region a unequal; short cirri equals 1/4 of body width, long cirri equals 1/2 of body width; cirri in region b reciprocally more or less equal in length, slightly shorter than long cirri in region a; cirri in region c short (Fig. 33A). Median ceratophore, large cirrophore on first dorsal cirri, and small inconspicuous cirrophores in region a, present; otherwise cirrophores absent. Median antenna, tentacular cirri, first dorsal cirri, short cirri in region a, cylindrical; long cirri in region a thick, slightly club shaped, cirri in region b flattened, slightly fusiform; cirri in region c cylindrical or slightly club shaped.

Parapodia with rounded conical neuropodial lobes, small to medium in size; parapodia in region b flattened and provided with well­developed notopodial lobes, equipped with a presetal triangular lamellae (Fig. 33C). Single neuropodial acicula in region a and c, 2 in region b; 2 anterodorsal and 3 thick and 4 thin posteroventral notopodial aciculae in region b. Neuropodial chaetal fascicle with c. 10 compounds. Compound chaetae with 2 small teeth (Fig. 33D), distal tooth somewhat smaller; serration present, well­developed (Fig. 33D). Single thick bayonet chaetae, distally dilated (Fig. 33D), beginning at chaetiger 1. Notopodial chaetal fascicle with c. 20 swimming chaetae (Fig. 33C), length 3/4 of body width. Pygidium with 2 short anal cirri.

Distribution. North West Pacific. Japan.

Remarks. As judged from the shape of the compound chaetae, it is probable that V. japonica is most closely related to V. c l a v a t a, and V. longipharyngea .

Virchowia longipharyngea ( Hartmann­Schröder, 1989) comb. n. (Fig. 34A–E)

Proceraea longipharyngea Hartmann – Schröder, 1989: 34, figs 52–55.

Material examined. Australia: holotype ZMH P­ 19670, Eden, Quarantine Bay, algae on rocks, 2 Jan 1976.

Diagnosis. Virchowia with long sinuated pharynx; compound chaetae with well­developed serration.

Description. Holotype incomplete, length 1.7 mm for 13 chaetigers, width 0.2 mm. Preserved material whitish, no colour markings. Ciliation not possible to assess.

Eyes separated (Fig. 34B); eye spots absent. Palps small, not projecting in front of prostomium, fusion not assessed. Nuchal epaulettes on outgrowths (Fig. 34B), originating from backside of prostomium, reaching chaetiger 2–3.

Median antenna reaching chaetiger 4. Lateral antennae and dorsal tentacular cirri, length 2/3 of median antenna. Ventral tentacular cirri 1/2 as long as dorsal pair. First dorsal cirri 4/5 as long as median antenna, second dorsal cirri equal in size to short dorsal cirri. From chaetiger 3–14 cirri with usual alternation in direction. Dorsal cirri from chaetiger 3, alternate in length; short cirri equals 2/3 of body width, long cirri equals two times body width; cirri with distinct alternation in placement, long cirri inserted dorsal to short cirri. Cirrophores present on tentacular cirri, and on all large cirri, cirrophores on short cirri either absent or very short. Cirrostyles unequal; cirrostyles on short cirri c. 1/ 3 in length of cirrostyles on long cirri; cirrophores on long cirri broad, distinct; cirrophores shorter than parapodial lobes; cirrophores shorter than cirrostyles. All appendages clavate (Fig. 34A).

Parapodial lobes small, rounded. Single acicula present in all chaetigers. Chaetal fascicle with 5–8 compounds in all chaetigers. Compound chaetae with 2 small teeth (Fig. 34E), distal tooth somewhat smaller; serration well­developed (Fig. 34E). Single thick bayonet chaetae, distally dilated (Fig. 34E), beginning at chaetiger 1.

Pharynx with numerous sinuations anterior and lateral to proventricle (Fig. 34C). Trepan in chaetiger 2, with c. 20 equal teeth. Basal ring present (Fig. 34D); absence/presence of infradental spines not possible to assess. Proventricle equal in length to 1 segment (Fig. 34C) in chaetiger 4–5 with c. 18 rows of muscle cells. Posterior part lost.

Reproduction. Unknown, but the holotype is a fragment of 13 chaetigers indicating the possibility of schizogamy by anterior scissiparity.

Habitat. Intertidal amongst algae.

Distribution. South West Pacific. South East Australia, only known from type locality.

Remarks. See remarks for V. c l a v a t a.

Virchowia pectinans ( Hartmann­Schröder, 1983) comb. n. (Fig. 35A–D)

Proceraea pectinans Hartmann­Schröder, 1983: 136 –137, figs 22–26.

Material examined. Australia: 1 paratype (male stolon) ZMH P­ 17402, Margaret river, Prevelly park, coralline algae on exposed rocks, 11 Nov 1975.

Diagnosis. Virchowia with 7 large and 10 smaller teeth in trepan, a pharynx with single sinuation; simple fused chaetae absent.

Description. Holotype lost. Description from literature ( Hartmann­Schröder 1983). Length 6 mm for 49 chaetigers, width 0.34 mm. No colour markings.

Eyes large; eye spots not mentioned. Palps in dorsal view projecting 1/2 of prostomial length, fusion not mentioned. Nuchal epaulettes broad, reaching end of chaetiger 1, possibly situated on outgrowths.

Median antenna lost, lateral antennae reaching chaetiger 2 ( Hartmann­Schröder 1983: fig. 22). Dorsal tentacular cirri shorter than lateral antennae, ventral tentacular cirri 1/2 as long as dorsal pair. First dorsal cirri longer than lateral antennae ( Hartmann­Schröder 1983: fig. 22). Dorsal cirri from chaetiger 2 alternate in length; long cirri equals 1/2 body width in anterior region, equal to body width in posterior region, short cirri distinctly shorter. Cirrophores not described, cirrostyles unequal. Lateral antennae and tentacular cirri more or less cylindrical, possibly slightly clavate ( Hartmann­Schröder 1983: fig. 22), short cirrostyles slightly clavate, first dorsal cirri and long cirrostyles thicker, slightly clavate ( Hartmann­Schröder 1983: fig. 22).

Parapodial lobes small, with "subaciculären lappen". Compound chaetae with small distal tooth; serration present. Single thick bayonet chaetae, distally dilated, beginning at chaetiger 1.

Pharynx with sinuation anterior to proventricle; trepan with c. 17 teeth, 7 large and 10 smaller, 1 large alternating with 1–2 smaller, arranged in 1 ring ( Hartmann­Schröder 1983: fig. 22). Proventricle equal in length to 2 segments in chaetiger 5–6 with c. 26 rows of muscle cells.

Reproduction. Schizogamy by anterior scissiparity behind chaetiger 13.

Morphology of epitokous stages. Male paratype incomplete, length 1.8 mm for 6+16 chaetigers, width 0.3 mm in region a, 0.5 in region b. Preserved material whitish, without colour markings. Ciliation not assessed.

Four eyes, with lenses; eyes situated on ventral and dorsal side of prostomium, ventral pair larger. Palps absent. Nuchal epaulettes as two short outgrowths, origination just lateral and posterior to median antenna.

Median antenna reaching chaetiger 3–4, equal in length to 1/5 of body length. Lateral bifid antennae as long as prostomial width; basal part 1/2 of total length; inner dorsal rami slightly longer than outer ventral. Frontal processes not possible to observe due to curled anterior appendages. Tentacular cirri 2 pairs (Fig. 35B); dorsal pair equal in length to 1/2 of prostomial width, ventral tentacular cirri 1/2 as long as dorsal pair. First dorsal cirri equal in length to median antenna; achaetous knobs absent. Second dorsal cirri situated above first chaetigerous lobe (Fig. 35B). Cirri from chaetiger 1 alternate in direction, with regular DU­groups (Fig. 35A, B); thus cirri on chaetiger 1, 3, 5 and so forth pointing down, and cirri on chaetiger 2, 4, 6 and so forth pointing up. Cirri in region a unequal (Fig. 35A, B); short cirri equals 1/3 of body width, long cirri equals body width; cirri in region b reciprocally equal, equal in length to short cirri in region a (Fig. 35A). Cirri in region a with distinct alternation in placement, long cirri inserted dorsal to short cirri. Median ceratophore not possible to assess, large cirrophores on first dorsal cirri, and cirrophores on large dorsal cirri, present; cirrophores otherwise absent or inconspicuous. Median antenna, and first dorsal cirri cylindrical, large cirri in region a swollen and clavate; tentacular cirri, short cirri in region a, and cirri in region b, thinner, slightly clavate.

Parapodia with rounded conical neuropodial lobes, small to medium in size; parapodia in region b flattened and provided with well­developed notopodial lobes, without presetal triangular lamellae. Single neuropodial acicula in region a, 2 in region b; 2–3 anterodorsal and 7–8 posteroventral notopodial aciculae in region b (Fig. 35D). Neuropodial chaetal fascicle with 5–12 compounds, similar to compounds in atokes (Fig. 35C). Thick bayonet chaetae, distally dilated (Fig. 35C), beginning at chaetiger 1. Notopodial chaetal fascicle with 10–15 swimming chaetae, length equal to body width in region b. Posterior part lost.

Habitat. Posidonia , Halophila , Corallina , intertidal, exposed.

Distribution. East Indian Ocean. South West Australia. Dunsborough, and Margaret River, Prevelly Park.

Remarks. Unfortunately the holotype has been lost, but Hartmann­Schröder's description is sufficiently good. The nuchal epaulettes would however need to be re­examined. They are described as being "lappenartig", and broad, but according to the picture it is possible that they are situated on outgrowths; further support for this is found in the male stolon paratype with its nuchal epaulettes on outgrowths. The long cirri are interpreted as being inserted dorsal to the short cirri as this is the situation in region a in the male paratype.

Virchowia spirifer ( Augener, 1913) comb. n. (Fig. 36A–F) Autolytus spirifer Augener, 1913: 260 –263, pl. 3, fig. 26–28, textfig. 41A–C. Procerastea cirrata Hartmann­Schröder, 1990: 57 –58, figs 27–29.

Material examined. Australia: holotype ZMH V­ 7976, Shark Bay, NNO from the northern point of Heirisson Prong, 11–12.5 m, 18 Jun 1905; holotype of Procerastea cirrata , ZMH P­ 19970, Brisbane, stony beach on Redcliffe Point north of city, intertidal, algae with sand, 23 Jan 1976.

Diagnosis. Virchowia with simple chaetae in all chaetigers together with 1–2 compounds; short cirri cylindrical, large cirri clavate, distally pointed; nuchal epaulettes as curled outgrowths.

Description. Holotype in poor condition, complete except for anal cirri and pharynx. Length 4.8 mm for 40 chaetigers, width 0.4 mm. Preserved material whitish, no colour markings. Holotype of P. cirrata in good condition, complete. Length 1.6 mm for 16 chaetigers, width 0.3 mm. Preserved material yellowish with white spots on cirri (Fig. 36A). Following description is based on the holotype of P. cirrata except where noted.

Ciliation not possible to assess. Eyes separated; eye spots present. Palps small, in dorsal view not projecting in front of prostomium (Fig. 36A), basally fused.

Nuchal epaulettes on outgrowths (Fig. 36A), originating from backside of prostomium, curled outwards like a cinnamon bun, reaching end of chaetiger 1 or beginning of chaetiger 2.

Median antenna lost. Lateral antennae reaching chaetiger 2. Dorsal tentacular cirri, length 2/3 of lateral antennae. Ventral tentacular cirri 1/2 as long as dorsal pair. First dorsal cirri reaching chaetiger 4, longer than lateral antennae, second dorsal cirri as long as ventral tentacular cirri. From chaetiger 1–12 cirri with usual alternation in direction, more posterior difficult to assess. Dorsal cirri from chaetiger 3 alternate in length (Fig. 36A); short cirri equals 1/2 of body width, long cirri equals 1.5 times body width. Cirri with distinct alternation in placement, long cirri inserted dorsal to short cirri. Cirrophores present on tentacular cirri, first dorsal cirri, and all dorsal cirri. Cirrophores and cirrostyles unequal; cirrophores on short cirri indistinct with thin base, cirrophores on long cirri broad, distinct; cirrostyles on short cirri c. 1/ 2 in length of cirrostyles on long cirri; cirrophores shorter than parapodial lobes; cirrophores shorter than cirrostyles. Lateral antennae, tentacular cirri, first dorsal cirri, short dorsal cirri, and anal cirri cylindrical, large cirri clavate, distally pointed (Fig. 36A). Most appendages lost in holotype of A. spirifer . Large cirrophores present on chaetiger 1, 4, 6, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, and 30 which agrees with the usual alternation in direction of cirri followed by 1 DDU­group.

Parapodial lobes rounded, small. All chaetigers with 1–2 aciculae. Chaetal fascicle with 4–5 fused chaetae, in anterior 6 chaetigers with very small distal tooth (Fig. 36C), in remainder chaetigers distal tooth still small, but more developed (Fig. 36E); faint denticulation present along fusion line (Fig. 36C, E); blade serration absent on fused chaetae (Fig.

36C, E). In addition 1–2 inferior compounds in most chaetigers, with small distal tooth (Fig. 36D); blade serration present. Single thick bayonet chaetae, distally dilated (Fig. 36F), beginning at chaetiger 6 (chaetiger 20 in holotype of A. spirifer ).

Pharynx with sinuation lateral to proventricle. Trepan in chaetiger 1 with c. 28 unequal teeth, 8 or 9 larger alternating with 19 or 20 smaller; 1 large alternating with 1–3 smaller (Fig. 36B), arranged in 1 ring. Basal ring present; infradental spines present (Fig. 36B). Proventricle equal in length to 1 segment in chaetiger 3, with 25–30 rows (25 in holotype of A. spirifer ) of muscle cells. Anal cirri equal in length to 1/2 of body width.

Reproduction and morphology of epitokous stages. Schizogamy by anterior scissiparity. The holotype of A. spirifer has a developing male stolon behind chaetiger 13. Stolon with four eyes, with lenses, in trapezoid arrangement, anterior pair larger; small bifid antennae, a median antennae, and small nuchal organs developed. No swimming chaetae.

Habitat. Algae, intertidal to 12 m.

Distribution. Indian Ocean, South West Pacific. East and West Australia.

Remarks. Virchowia spirifer is unique among Virchowia in possessing simple fused chaetae. These chaetae are most similar to those found in the anterior two chaetigers of Imajimaea draculai . In other respects, such as shape of dorsal cirri, trepan structure, and bayonet­type, the two taxa are dissimilar. The synonymy of P. cirrata is concluded from examination of type material, that agree in every detailed with Augener's material.