Scyphoproctus paivai,

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: 104-107

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-FFDA-3D26-6DA4-F9BFFBD44CA0

treatment provided by

Plazi

scientific name

Scyphoproctus paivai
status

sp. nov.

Scyphoproctus paivai  sp. nov.

( Figures 5View FIGURE 5 ̄7)

Type series. Holotype ( ZUEC POL 20591View Materials): state of São Paulo, São Sebastião, Araçá Bay (23°48'S, 45°24'W): coll. 15 Feb 2013; rocky shore; intertidal; 1 specGoogleMaps  . Paratypes: state of São Paulo, São Sebastião, Araçá Bay (23°48'S, 45°24'W): paratypes 1 and 2 ( ZUEC POL 20571View Materials): coll. 19 Mar 2015; rocky shore; intertidal; 2 specsGoogleMaps  . Paratypes 3–11 ( ZUEC POL 20574View Materials): coll. 16 May 2014; rocky shore; intertidal; 9 specs  . Paratype 12 ( ZUEC POL 20575View Materials): coll. 10 Nov 2013; rocky shore; intertidal; 1 spec  . Paratype 13 ( ZUEC POL 20577View Materials): coll. 29 Oct 2011; soft-bottom; intertidal; Stn. 20(2)A; 1 spec. State of São Paulo, São Sebastião, São Francisco Beach (23°44'54"S, 45°24'34"W): paratype 14 ( ZUEC POL 20580View Materials): coll. 23 Jun 2013; sandy beach; Stn. 45; 1 specGoogleMaps  . Paratypes 15–17 ( ZUEC POL 20581View Materials): coll. 23 Jun 2013; sandy beach; Stn. 72; 3 specs  . Paratypes 18 and 19

(ZUEC POL 20582View Materials): coll. 23 Jun 2013; sandy beach; Stn. 48; 2 specs. Paratypes 20–25 (ZUEC POL 20583View Materials): coll. 11 Apr 2013; sandy beach; Stn. 20P; 6 specs. Paratype 26 (ZUEC POL 20590View Materials): coll. 0 4 Oct 1995; sandy beach; 1 spec. State of Paraíba, Cabo Branco Beach (7°08'S, 34°47'W): paratypes 27–29 (ZUEC POL 20587View Materials): coll. 0 1 Feb 2010; in rhodoliths; intertidal; 3 specs.

Additional material examined. State of São Paulo, São Sebastião, Araçá BayGoogleMaps  (23°48'S, 45°24'W). (ZUEC POL 20572View Materials): coll. 15 Feb 2013; rocky shore; intertidal; 5 specs. (ZUEC POL 20573View Materials): coll. 26 Sep 2011; softbottom; intertidal; Stn. 4(3)A; 1 spec. (ZUEC POL 20576View Materials): coll. 23 Feb 2013; soft-bottom; intertidal; Stn. 152(1)G; 1 spec. (ZUEC POL 20578View Materials): coll. 12 Oct 2012; soft-bottom; intertidal; Stn. 3(2)Pr; 1 spec. (ZUEC POL 20579View Materials): coll. 0 8 Feb 2012; soft-bottom; intertidal; Stn. 66(2)Pr; 1 spec. State of São Paulo, São Sebastião, São Francisco Beach GoogleMaps  (23°44'54"S, 45°24'34"W). (ZUEC POL 20584View Materials): coll. 11 Apr 2013; sandy beach; intertidal; Stn. 5G; 2 specs. (ZUEC POL 20585View Materials): coll. 23 Jun 2013; sandy beach; intertidal; Stn. 43; 3 specs. State of São Paulo, Caraguatatuba, Enseada Beach GoogleMaps  (23°43'40"S, 45°25'10"W). (ZUEC POL 20586View Materials): coll. 12 Apr 2013; sandy beach; intertidal; Stn. 47P; 3 specs. State of Paraíba, Cabo Branco Beach GoogleMaps  (7°08'S, 34°47'W). (ZUEC POL 20588View Materials): coll. 0 8 Feb 2009; in rhodoliths; intertidal; 1 spec. State of Paraíba, Jacumã Beach GoogleMaps  (7°14'S, 34°47'W). (ZUEC POL 20589View Materials): coll. 29 Jan 2010; in rhodoliths; intertidal; 1 spec.

Comparative material. Scyphoproctus edmondsoni Magalhães & Bailey-Brock, 2012  , holotype USNM 1191161—Nuupia Pond, Hawai, 21°25'58.8'' N, 157°44′52.8″ W, paratypes USNM 1191162— Nuupia Pond , Hawai, 21°25'58.8'' N, 157°44'52.8'' WGoogleMaps  .

Description. Complete holotype 21 mm long, 0.9 mm wide for 83 chaetigers. Complete specimens ranged from 2.5– 15 mm, long 0.3–1.1 mm wide and 24–79 chaetigers; incomplete specimens ranged from 0.3–2.2 mm wide. Body rounded; thorax wider than abdomen; abdomen slightly narrowing toward pygidium ( Fig. 5AView FIGURE 5). Whitish color in alcohol.

Prostomium rectangular, 2x longer than wide, rounded on anterior end ( Figs 5AView FIGURE 5; 6BView FIGURE 6 ̄C; 7A); nuchal organs not observed; eyespots as a pair of densely pigmented red areas forming inverted “U” ( Figs 5AView FIGURE 5; 6CView FIGURE 6). Proboscis globular-shaped, with several robust papillae ( Fig. 6CView FIGURE 6). Peristomium longer than achaetous segment 1 ( Figs 5AView FIGURE 5; 6BView FIGURE 6; 7AView FIGURE 7). Complete inter-segmental groove between peristomium and achaetous segment ( Figs 5AView FIGURE 5; 7AView FIGURE 7).

Thorax with 11 segments, including peristomium, one additional achaetous segment, and 9 chaetigers. Bilimbate capillaries in noto- and neuropodia of chaetigers 1–9. Thorax smooth with chaetigers 1 biannulate; shallow 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, more conspicuous on larger specimens. Transition between thorax and abdomen subtle, marked mainly by chaetal change ( Figs 5AView FIGURE 5; 6AView FIGURE 6; 7AView FIGURE 7).

Abdominal chaetigers without capillaries. Abdominal notopodia and neuropodia with well-developed tori pads and well-separated, distance between tori remaining similar throughout abdomen ( Fig. 6FView FIGURE 6). First abdominal notopodium with 9 hooks; first abdominal neuropodium with 11 hooks; number of hooks in both rami increases on next two to three chaetigers and afterwards reduces toward posterior end. Notopodial hooks (seen with SEM) with round and large main fang, right angle with shaft, surmounted by more than 20 teeth arranged in 4–5 rows (3–4 basally, intercalated among all teeth of tori ( Fig. 7CView FIGURE 7 ̄D); remaining teeth smaller and with diversified arrangement); thick hood with smooth margin ( Fig. 7CView FIGURE 7 ̄D). Neuropodial hooks (with SEM) with pointed and large main fang, right angle with shaft, surmounted by 15–16 teeth arranged in three rows (3–4 basally, intercalated among the teeth of the tori; 5–6 median; 6–7 apically); thin hood with fringed margin (uneven and pointed fringes) ( Fig. 7EView FIGURE 7).

Four pre-pygidial segments with neuropodial hooks and notopodial spines (3,3,3,2, each side). Anal plaque poorly developed, “w”-shaped, with one set of protruding spines (1 spine on each side). Large anal aperture between anal cirri; two short and broadly rounded cirri without membrane ( Figs 5View FIGURE 5 B–C; 6D; 7B).

Variation. Paratypes with 11–12 segments, including the peristomium, one additional achaetous segment, and 9–10 chaetigers. Number of hooks of the first abdominal lobe size dependent, notopodium ranging from 2 to 40 and neuropodium from 5 to 43 hooks.

Methyl green staining pattern. Chaetigers 1 and 2 with two longitudinal bands of large dark speckles on anterior and posterior parts of the segments, spaced equally from each other; chaetigers 6–9 staining with small dark speckles, number of speckles increasing toward chaetiger nine; first two abdominal chaetigers staining darkly around the noto- and neuropodial tori and leaving the glandular pad unstained ( Fig. 6EView FIGURE 6).

Remarks. Scyphoproctus paivai  sp. nov. belongs to a group of species with a poorly developed anal plaque, which includes S. armatus  and S. edmondsoni  . Scyphoproctus armatus  differs from Scyphoproctus paivai  sp. nov. by the number of thoracic chaetigers, number of pre-pygidial segments with acicular spines, and shape of anal cirri. Scyphoproctus armatus  has nine thoracic chaetigers and Scyphoproctus paivai  sp. nov. has 9–10. The number of pre-pygidial segments with acicular spines in S. armatus  is 8–11 and in Scyphoproctus paivai  sp. nov. is four. Anal cirri are digitate in S. armatus  and “w”-shaped in Scyphoproctus paivai  sp. nov.

Scyphoproctus edmondsoni  also has 9–10 thoracic chaetigers, abdominal noto- and neuropodia with wellseparated glandular tori pads, and inflated anal cirri, but it differs from Scyphoproctus paivai  sp. nov. by the number of pre-pygidial segments with acicular spines (only one) and by the hooded hooks (number and arrangement of teeth and shape and thickness of the hood). Hooded hooks in Scyphoproctus paivai  sp. nov. are different between noto- and neuropodia. Notopodial hooks have more than 20 teeth arranged in 4–5 rows and thick hoods with smooth margins; neuropodial hooks have 15–16 teeth arranged in three rows and thin hoods with a fringed margin (uneven and pointed fringes). On the other hand, hooded hooks of S. edmondsoni  are similar between noto- and neuropodia, with several teeth arranged in 3–4 rows, and with a thick and smooth hood.

Etymology. This species is named after the Prof. Paulo de Cesar Paiva from the Universidade Federal do Rio de Janeiro, an expert in benthic ecology, marine phylogeography, and polychaete systematics; an exceptional teacher; and specially a great friend.

Habitat. From intertidal to shallow subtidal regions (0–0,5m), in soft-bottom, rhodoliths and rocky shore.

Type locality. Araçá Bay , São Paulo, Brazil, 23°48'S, 45°24'W (South Atlantic Ocean)GoogleMaps  .

Distribution. South Atlantic Ocean: Brazil (states of Paraíba and São Paulo).

ZUEC

Museu de Zoologia da Universidade Estadual de Campinas