Epigamia
- Dataset
- Revision of Autolytinae (Syllidae: Polychaeta).
- Rank
- GENUS
- Published in
- Nygren, Arne (2004): Revision of Autolytinae (Syllidae: Polychaeta). Zootaxa 680: 1-314, ISBN: 1-877354-52-X, DOI: 10.5281/zenodo.157809
Classification
- kingdom
- Animalia
- phylum
- Annelida
- class
- Polychaeta
- order
- Phyllodocida
- family
- Syllidae
- genus
- Epigamia
description
Description. Length 4.5 – 17.2 mm for 27 – 88 chaetigers, width 0.20 – 0.72 mm. Live specimens from faint reddish or yellowish, sometimes with 3 faint red lines, to more intensely red anterior to proventricle, intestinal region orange to redbrown; anterior appendages redtipped; eyes red. Preserved specimens without colours. Ciliation as 2 trochs per segment. Eyes confluent (Fig. 83 B); eye spots present. Palps in dorsal view projecting c. 1 / 3 of prostomial length. Nuchal epaulettes reaching between end of chaetiger 1 (small individuals), and end of chaetiger 2 (Fig. 83 A, B). Median antenna reaching chaetiger 7 – 15 (n = 10) in live specimens. Lateral antennae and dorsal tentacular cirri, length 1 / 2 – 2 / 3 of median antenna. Ventral tentacular cirri 1 / 3 – 1 / 2 as long as dorsal pair. First dorsal cirri 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 1 DDUgroups, 1 – 3 DDUUgroups, and 1 – 13 DDUgroups (n = 6). Dorsal cirri from chaetiger 3, alternate in length (Fig. 83 A); short cirri equals 1 / 2 – 2 / 3 of body width, long cirri equal or slightly longer than body width. Cirrophores present on tentacular cirri, and all dorsal cirri. Cirrophores equal, cirrostyles unequal; short cirrostyles 1 / 2 – 2 / 3 in length of long cirrostyles; cirrophores shorter than parapodial lobes; cirrophores shorter than cirrostyles. All appendages cylindrical. Parapodial lobes large, rounded, slightly swollen dorsal to chaetal fascicle. 2 – 4 aciculae in anterior chaetigers, 1 – 2 in median and posterior. Chaetal fascicle with 9 – 18 compounds in anterior chaetigers, 3 – 13 in median and posterior. Compound chaetae with large distal tooth (Fig. 83 F); serration present. Single thin bayonet chaetae (Fig. 83 G), beginning between chaetiger 3 – 30. Pharynx with from one sinuation (small individuals) anterior to proventricle to multiple sinuations anterior and lateral to proventricle (Fig. 83 D). Trepan in chaetiger 1 – 4, with 34 – 44 unequal teeth, 9 large teeth and 25 – 35 smaller; 1 large alternating with 2 – 4 much smaller, in 2 rings, small teeth situated slightly inside large teeth (Fig. 83 E). Basal ring present; infradental spines present (Fig. 83 E). Proventricle equal in length to 2 – 4 segments in chaetiger 6 – 18 with 34 – 44 rows of muscle cells (n = 11). Anal cirri equal in length to 1 – 2 times the body width. Reproduction. Epigamy (Fig. 83 C, D). Epitokous specimens caught in February to May in the North Atlantic (Hamond 1969 b). Transforming individuals observed in January in the North Pacific (pers. obs.).
description
Male. Body divided into 3 regions, anterior with 11 (see E. noroi) or 14 uniramous chaetigers (region a), median with c. 37 biramous chaetigers (region b), and posterior with 3 – 23 uniramous chaetigers (region c). Body widest in anteromedian half of region b; body width measured in region a, as body width excluding parapodial lobes, and in region b, at the widest part, as body width including parapodial lobes. Ciliation as in atokes. Prostomium rounded rectangular, wider than long, with straight or concave anterior margin. Eyes large, 2 pairs, with lenses; eyes situated on dorsal and ventral side of prostomium, ventral pair larger. Palps present, much smaller than in atokes. Nuchal epaulettes as in atokes. Large median antenna inserted medially on prostomium, lateral antennae inserted on anterior margin. Lateral antennae bifid, basal part c. 1 / 2 of total length; outer ventral rami equal or longer than inner dorsal rami. Basal part and inner dorsal rami segmented with abundant cilia. Pair of small frontal processes inserted anterolaterally to dorsal pair of eyes. Tentacular cirri as in atokes. First dorsal cirri, larger than in atokes, equal in shape and size to median antenna. Achaetous knobs absent. Cirri with alternation in direction and size in region a, and c as in atokes; cirri in region b with less obvious alternation in both size and direction. However, this needs to be explored using a larger samplesize. Cirri length measured as body width excluding parapodial lobes in region a, and c; as body width including parapodial lobes in region b. Median antenna with large ceratophore, large cirrophores present on first dorsal cirri; cirrophores otherwise as in atokes. Appendages cylindrical, suspected to be flattened in epitokes of E. macrophtalma. Pharynx and proventricle disintegrates at some stage, and is totally absent in fully developed epitokes. Neuropodia as in atokes but generally larger and with enlarged, and prolonged dorsal part, especially in region b; in region b also with welldeveloped flattened notopodial lobes. Neuropodial aciculae as in atokes; notopodia in region b supported by c. 3 anterodorsal aciculae, and 3 – 4 thick and 3 – 5 thin posteroventral aciculae. Neuropodial chaetae as in atokes. Notopodial lobes with 20 – 50 swimming chaetae, in length equal to c. body width in region b including parapodial lobes. Pygidium as in atokes. Female. Body divided into 3 regions, anterior with 14 uniramous chaetigers (region a), median with 29 – 41 biramous chaetigers (region b), posterior with 16 – 33 uniramous chaetigers (region c). Body width fairly constant, slightly wider in region b; body width measured in region a, as body width excluding parapodial lobes, and in region b as body width including parapodial lobes. Ciliation as in atokes. Prostomium rounded rectangular, wider than long, with straight or concave anterior margin. Eyes large, 2 pairs, with lenses; eyes situated on dorsal and ventral side of prostomium, ventral pair larger. Palps present, much smaller than in atokes. Nuchal epaulettes as in atokes. Median antenna inserted medially on prostomium, lateral antennae inserted on anterior margin. Tentacular cirri as in atokes. Achaetous knobs absent. Cirri with alternation in direction as in atokes, except for cirri in region b with less obvious alternation; cirri length as in atokes or longer. Cirri length measured as body width excluding parapodial lobes in region a, and c; as body width including parapodial lobes in region b. Cirrophores as in atokes. Appendages cylindrical, suspected to be flattened in epitokes of E. macrophtalma. Pharynx and proventricle disintegrates at some stage, and is totally absent in fully developed epitokes. Neuropodia as in atokes but generally larger and with enlarged, and prolonged dorsal part, especially in region b; in region b also with notopodial lobes, not as developed as in male. Neuropodial aciculae as in atokes; notopodia in region b supported by 5 – 14 anterodorsal aciculae, and 6 – 8 thick and 6 – 9 thin posteroventral aciculae. Neuropodial chaetae as in atokes. Notopodial lobes with 25 – 50 swimming chaetae, in length equal to c. body width in region b including parapodial lobes. Pygidium as in atokes.
diagnosis
Diagnosis. Epigamia with a DDUgroup posterior to chaetiger 27, a much convoluted pharynx, and a trepan with 1 large teeth alternating with 2 – 4 much smaller.
materials_examined
Material examined. Greenland: holotype (female epitoke) SMNH 2438, West Greenland, Davis Strait, 65 ° N 60 ° W, Swedish arctic expedition 1859. Norway: holotype (female epitoke) of Autolytus newtoni SMNH 2437, Spitsbergen, Storfjord, 78 ° 37 ' N 19 ° E, 21 Aug 1864. Russia: holotype ZMMSU 849, and 4 paratypes ZMMSU 850 – 853 of Proceraea rzhavskyi, Mednyy Island (Commander Islands), Gladkovskaya Bay, 54 ° 44 ' N 167 ° 45 ' E, 6 m, on hydroid Abietinaria turgida, 1986. Faroes: 35 spms (15 spms in formalin, 18 spms on slide, 2 spms in author's collection for DNA analyses), South of Vagar, 61 ° 56.8 ' N 06 ° 59.5 ' W, triangledredge, 76 – 78 m, hydroids, 27 Jun 1997; 7 spms (1 spm in formalin, 6 spms in author's collection for DNA analyses), East of Nolsøy, 62 ° 01.5 ' N 06 ° 31.9 W, triangle dredge, 41 m, bedrock, 27 Jul 1997; 29 spms (17 spms in formalin, 9 spms on slides (2 rear ends in author's collection for DNA analyses), 3 spms in author's collection for DNA analyses), East of Bordøy, 62 ° 24.6 ' N 06 ° 26.3 ' W, triangle dredge, 65 – 68 m, shellgravel with hydroids, 17 Jul 1997; 7 spms (6 spms on slides, 1 in author's collection for DNA analyses), East of Bordøy, 62 ° 08.4 ' N 06 ° 23.4 ' W, triangle dredge, 77 m, shellgravel with hydroids, 17 Jul 1997. France: 11 syntypes of Autolytus longeferiens MNHN 1031 – 1041, Dinard, Jun – Aug 1872 – 1881; holotype of Autolytus paradoxus MNHN 1030, Dinard, 18 Jul 1887. USA: 8 spms (4 spms in formalin (2 rear ends in author's collection for DNA analyses), 2 spms on slides (rear ends in author's collection for DNA analyses), 2 spms in author's collection for DNA analyses), Rock Pt and López Island, 48 ° 29.6 ' N 122 ° 56.9 ' W, dredge, 75 m, Polycarpa sp., barnacles with rich hydroid fauna, few sponges, 24 Jan 2001.
Name
- Homonyms
- Epigamia