Scyphoproctus oculatus Reish, 1959 Amended, Reish, 1959

Silva, Camila Fernanda Da & Amaral, Antonia Cecilia Zacagnini, 2019, Scyphoproctus Gravier, 1904 (Annelida, Capitellidae): description of three new species and relocation of Heteromastides Augener, 1914 in Scyphoproctus, Zootaxa 4560 (1), pp. 95-120: 101-103

publication ID

https://doi.org/10.11646/zootaxa.4560.1.5

publication LSID

lsid:zoobank.org:pub:33C0A0BC-5124-4C75-92E1-1AB5862D04D4

persistent identifier

http://treatment.plazi.org/id/6E3187A3-FFD5-3D22-6DA4-FF47FE324AE7

treatment provided by

Plazi

scientific name

Scyphoproctus oculatus Reish, 1959 Amended
status

 

Scyphoproctus oculatus Reish, 1959 Amended  

( Figures 2 View FIGURE 2 ̄3)

Scyphoproctus oculatus Reish, 1959: 78   ̅80; figs. 1̅6.

Material examined. Scyphoproctus oculatus Reish, 1959   , holotype LACM-AHF POLY 481—(33°36'59'' N, 117°54'18'' W): 26.3m deep, Orange County, Newport, California, USA, 1 spec.

Description. Holotype 20 mm long, 1.0 mm wide for 97 chaetigers. Body thin; thorax same width as anterior abdomen ( Fig. 3A View FIGURE 3 ). Yellowish color in alcohol.

Prostomium broadly rounded, in demilune shape, base 1.5x wider than long ( Fig. 2A View FIGURE 2 ); nuchal organs not observed; eyespots as a pair of elliptical-shaped areas on each side ( Fig. 2A View FIGURE 2 ). Proboscis globular-shaped, papillae not observed. Peristomium 1.5x longer than achaetous segment ( Figs 2A View FIGURE 2 ; 3A View FIGURE 3 ). Incomplete inter-segmental groove between peristomium and achaetous segment ( Figs 2A View FIGURE 2 ; 3A View FIGURE 3 ).

Thorax with 13 segments, including the peristomium, one additional achaetous segment, and 11 chaetigers. Bilimbate capillaries in notopodia and neuropodia of chaetigers 1–11. Thorax smooth with chaetigers strongly biannulate; moderate depth of inter-segmental grooves between chaetigers. First chaetiger biramous. Parapodial lobes well-separated; notopodia inserted dorso-laterally and neuropodia laterally. Lateral organs present from the achaetous segment. Transition between thorax and abdomen conspicuous, marked mainly by chaetal change and appearance of parapodial lobes ( Fig. 3A View FIGURE 3 ).

Abdominal chaetigers without capillaries. Abdominal notopodia and neuropodia with well-developed tori pads. First notopodial lobes together ( Fig. 3B View FIGURE 3 ), distance between lobes increasing along abdomen; neuropodial lobes separated, with nearly same distance throughout abdomen. Notopodial hooks (light microscopy) with large and triangular main fang, surmounted by approximately 10 teeth arranged in three rows in lateral view.

Four pre-pygidial segments with neuropodial hooks and notopodial spines—3, 3, 2, 2 spines per notopodial lobe, greater number of spines near anal plaque ( Fig. 2C View FIGURE 2 ). Anal plaque well-developed, circle-shaped, with five sets of spines protruding from plaque margin (5,3,2,2,1, each side) ( Fig. 2 View FIGURE 2 B–C). Median-sized anal aperture on inferior third of plaque, beginning as a slit from base of anal cirri ( Fig. 2B View FIGURE 2 ). Two short and robust cirri, 1.5x longer than wide and base 3x wider than distal end; without a median membrane ( Figs 2 View FIGURE 2 B–C; 3C–D).

Remarks. According to drawings and original description, Scyphoproctus oculatus   lacks the achaetous segment. All Scyphoproctus   species present an achaetous segment, posterior to peristomium, and the intersegmental groove between peristomium and achaetous segment may be complete or incomplete; when it is incomplete, the delimitation between both segments may not be conspicuous. Re-examination of the type material made possible to confirm that S. oculatus   presents an achaetous segment with an incomplete inter-segmental groove, unnoticed in the original description.

The original description presents a variation on the number of acicular spines in the anal plaque; however, together with the holotype there were some specimens that were not S. oculatus   and some small posterior fragments; in this way the re-description was made based only on the holotype (that it was complete) in order to avoid any possible mistake.

Kingdom

Animalia

Phylum

Annelida

Class

Polychaeta

Order

Capitellida

Family

Capitellidae

Genus

Scyphoproctus

Loc

Scyphoproctus oculatus Reish, 1959 Amended

Silva, Camila Fernanda Da & Amaral, Antonia Cecilia Zacagnini 2019
2019
Loc

Scyphoproctus oculatus

Reish, D. J. 1959: 78
1959