Spio pigmentata, Lee & Meißner & Yoon & Min, 2021
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publication ID |
https://dx.doi.org/10.3897/zookeys.1070.73847 |
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publication LSID |
lsid:zoobank.org:pub:73661A23-F563-4D58-9A81-E55AB3CFCF45 |
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persistent identifier |
https://treatment.plazi.org/id/C4BA64C6-C570-4D77-A3BC-49722FC36934 |
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taxon LSID |
lsid:zoobank.org:act:C4BA64C6-C570-4D77-A3BC-49722FC36934 |
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treatment provided by |
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scientific name |
Spio pigmentata |
| status |
sp. nov. |
Spio pigmentata sp. nov.
Spio filicornis : Paik, 1975: 420, 1982: 808, 1989: 465, fig. 175.
Spio sp. 2: Abe and Sato-Okoshi, 2021: 63, fig. 9L-N.
Material examined.
Type locality. Yellow Sea , Korea, 36°15'42.9"N, 126°32'47.9"E, intertidal sand. Holotype. Complete, without palps, formalin (NIBRIV0000888168) (Fig. 2 View Figure 2 ), 21 Oct. 2020. Paratypes. Four complete (NIBRIV0000888164-7), three complete ( SMF 30259 View Materials ), two complete (ZMH P-30424), formalin, Yellow Sea, Korea, 37°26'50.0"N 126°22'3.9"E, 13 Jan. 2021, intertidal sand GoogleMaps .
Non-type materials. Yellow Sea , Korea, intertidal sand: 27 anterior fragments (af), formalin, 34°18'43"N, 126°1'59"E, 22 Aug. 2017; 1 complete (NIBRIV0000862794), 33 af, formalin, 34°41'22.5"N, 125°25'43.8"E, 16 May. 2018; 71 af, formalin, 35°40'45.2"N, 126°31'26.5"E, 18 Mar. 2018; 14 af, 95% ethanol, 35°38'03.4"N, 126°27'57.2"E, 17 May. 2018; 5 af, 95% ethanol, 35°39'16.4"N, 126°29'26.0"E, 19 Sep. 2020; 4 af, 95% ethanol, 35°35'44.6"N, 126°29'07.9"E, 18 Sep. 2020, 5 complete, formalin, 4 af (NIBRIV0000888159-60), 95% ethanol, 35°35'44.6"N, 126°29'07.9"E, 19 Sep. 2020; 1 af, formalin, 35°40'44.2"N, 126°31'29.7"E, 21 Sep. 2020; 1 af, formalin, same locality as holotype, 21Oct. 2020; 9 complete, 1 af, formalin, same locality as paratypes, 15 Jan 2021. Korea Strait, Korea: 10 af, formalin, 34°28'05.5"N, 127°28'16"E, 26 May. 2017, intertidal sand; 3 complete, 22 af, formalin, 34°11'03.7"N, 126°54'37.5"E, 26 Jul. 2017, intertidal sand; 2 af, 95% ethanol, 34°53'19.9"N, 128°26'41.2"E, 20 Jul 2020, intertidal muddy sand; 5 af, formalin, 35°40'44.2"N, 126°31'29.7"E, 21 Sep. 2020, intertidal sand; 1 af, formalin, 2 complete (NIBRIV0000888162-3), 95% ethanol, 34°55'37.7"N, 128°02'13.3"E, 23 Jun. 2020, muddy sand between gravel and macrophytes; 8 complete, 2 af, formalin, 1 af (NIBRIV0000888161), 95% ethanol, 34°43'45.1"N, 127°57'09.7"E, intertidal sand; 1 af, formalin, 36°13'53.3"N, 126°31'47.2"E, 20 Oct. 2020, intertidal sand; 1 af, formalin, 36°09'41.2"N, 126°31'11.1"E, 20 Oct. 2020, intertidal sand GoogleMaps .
Diagnosis.
Prostomium broadly rounded, slightly expanded at anterolateral margin, extending to chaetiger 1; nuchal organs with short median and long lateral ciliary bands, lateral bands extending up to transverse ciliated band (tcb) of chaetiger 3. Metameric dorsal ciliated organs double-paired, present from chaetiger 3. Branchiae from chaetiger 1 to almost end of body, length of first pair slightly shorter than that of second pair; branchiae mostly free from notopodial lamellae. White dots present from about chaetiger 3 to the end of the middle body region; three pairs of white dots per chaetiger. Neuropodial hooded hooks tridentate, present from chaetiger 11, uppermost tooth very inconspicuous. Pygidium with thin dorsolateral pair and stout but slightly longer ventral pair of anal cirri.
Description.
Holotype complete specimen with 67 chaetigers, about 15.7 mm in length and about 1.0 mm in width (Fig. 2 View Figure 2 ). Other specimens complete with 58-73 chaetigers, 12.0-17.0 mm in length and 0.9-1.2 mm in width.
Prostomium entire and rounded anteriorly, slightly expanded at anterolateral margin, extending to chaetiger 1; prostomium with orange-brown pigmentation on anterior part, middle part of prostomium comparatively broad, posterior part with highly elevated papilla; two pairs of black eyes arranged in trapezoid; anterior pair larger, slightly crescent-shaped or oval, widely spaced; posterior pair smaller, rounded, closely spaced; weak transverse depression between anterior and middle part of prostomium (Figs 3A, B View Figure 3 , 6A View Figure 6 , 7A View Figure 7 ). Peristomium separated from prostomium by a narrow furrow (Fig. 7A View Figure 7 ). Peristomial palps reaching chaetigers 6-9 (Fig. 5A View Figure 5 ).
Nuchal organs and metameric dorsal ciliated organs distinctly observed in well-preserved and live specimens; nuchal organs U-shaped due to posterior fusion of median and lateral ciliated bands, long and recurved on chaetiger 2, and reaching to first transverse ciliated band (tcb) on chaetiger 2 (Figs 3A View Figure 3 , 6A View Figure 6 , 7A View Figure 7 ). Metameric dorsal ciliated organs double paired, present from between branchiae 3 and 4 (i.e., after second tcb), extending up to chaetiger 40 in holotype (38-47 in 62-73 chaetiger individuals) (Figs 3A View Figure 3 , 5 View Figure 5 , 6A View Figure 6 , 7A View Figure 7 ). White dots present from chaetiger 3 to chaetiger 50 in holotype (42-52 in 62-73 chaetiger individuals); three pairs of white dots per chaetiger; lateral two pairs closely spaced (Figs 5B View Figure 5 , 6B, C View Figure 6 , 7B View Figure 7 ). Intersegmental transverse ciliation absent.
Branchiae present from chaetiger 1 to almost end of body, absent only on last 2 or 3 (rarely 4) chaetigers (Fig. 2 View Figure 2 ); length of first pair of branchiae two-thirds to four-fifths the length of second pair (Fig. 3A, B View Figure 3 ); comparatively longest and widest branchiae on chaetigers 2-12, becoming thinner and shorter posteriorly; about last 10 branchiae distinctly shorter and thinner; branchiae with cilia on inner and furrow on outer side; branchiae mostly separated from postchaetal notopodial lamellae (Fig. 4 View Figure 4 ). Notopodia on chaetiger 1 slightly shifted dorsally; notopodial postchaetal lamellae almost lanceolate (Fig. 4A View Figure 4 ); from chaetiger 2 lamellae broadly rounded, slightly tapered superiorly (Fig. 4B-D View Figure 4 ), becoming smaller in middle to posterior chaetigers (Fig. 4F View Figure 4 ), and larger, subtriangular in about last 17 chaetigers (Fig. 4G View Figure 4 ). Neuropodial postchaetal lamellae rounded in about first four chaetigers, becoming broader and larger in along anterior and middle chaetigers, largest in posteriormost chaetigers (Fig. 4 View Figure 4 ).
Notopodial chaetae all capillaries; notochaetae in anterior and middle chaetigers arranged in two rows; notochaetae of anterior row with stout sheath, heavily granulated, slightly shorter than chaetae of posterior row, granulation disappearing in middle chaetigers; notochaetae of posterior row thinner, with narrow sheath, non-granulated; additional fascicle of 6-9 very long, thin capillaries without granulations present at superior position, longest in first three chaetigers; notochaetae in posterior chaetigers thin and long, arranged in irregular rows. Neuropodial chaetae with granulated or non-granulated capillaries, hooded hooks, and inferior fascicle of capillaries; capillaries of anterior neuropodia arranged in two rows; neurochaetae of anterior row with distinct sheaths, stout, heavily granulated (Fig. 3E View Figure 3 ); neurochaetae of posterior row non-granulated, less stout, replaced by 7-9 hooded hooks from chaetiger 11 (rarely 12); neuropodial hooded hooks tridentate, main fang well developed, uppermost tooth inconspicuous (Fig. 3F View Figure 3 ); inferior fascicle of 2-5 long, thin, non-granulated capillaries from chaetiger 1, replaced by 2-4 (usually 3) stout granulated, ventral sabre chaetae in inferiormost position from about chaetigers 16-19 (rarely 13-15) (Fig. 3D View Figure 3 ).
Pygidium with two pairs of anal cirri; dorsolateral pair shorter and thinner, comparatively widely spaced, and ventral pair longer, very stout, conical with rounded tip and closely spaced (Fig. 3C View Figure 3 ).
Pigmentation.
Highly variable but conspicuous in live or well-preserved specimens (some specimens without pigmentation). Palps in live specimens with variable pigmentation, about 6-15 light to dark brown spots or black ringed appearance (Fig. 5A, B View Figure 5 ); pigmentation fades in formalin- and ethanol-fixed specimens, but light brown pigmentation along the food groove remains. Well-preserved specimens with orange-brown and black pigmentation as follows: medial part of prostomium with orange-brown pigmentation, often faded in formalin- and ethanol-fixed specimens; prostomium with black pigmentation on the anterior to transverse depression margin of the prostomium, dorsal side of the peristomium next to the prostomium; black pigmented patches in front of, and in particular, behind tcb dorsolaterally in about the first six chaetigers in holotype (Fig. 6A View Figure 6 ), and some specimens with distinct patches (Fig. 5B View Figure 5 ). If black pigmented patches are distinct on the ventral side, white dots (pores of ventral glands) are clearly visible (Figs 5D View Figure 5 , 6B View Figure 6 ).
Methyl green staining pattern (MGSP).
The anterior part of the prostomium and peristomium, margins of branchiae and postchaetal lamellae, and anal cirri were intensively stained. Transfer of stained specimens to distilled water for approximately 10 min, resulted in white dots being visible against the bluish background on the ventral side (Fig. 6C View Figure 6 ). Three pairs of dots were visible on chaetiger 3 to end of middle body region; lateral two pairs closely spaced, easily confused as one pair.
Biology.
In the present study, the specimens were found mostly in intertidal zones of fine sand, rarely muddy sand, and sometimes a mixture of gravel and macrophytes ( Zostera marina ). According to Abe and Sato-Okoshi (2021), planktonic larvae of Spio sp. 2 with two rows of black melanophore spots on each side of the dorsum from chaetiger 1 onward, linked by band-shaped medial black pigmentation from chaetiger 4 or 5 are found in Sasuhama and Onagawa Bay between April and August (see cited publication for further details). Adult specimens were collected from muddy sand sediments of shallow waters in Sasuhama, Japan ( Abe and Sato-Okoshi 2021).
Etymology.
The specific name, Spio pigmentata , originates from the Latin word pigmentum, meaning “pigment” This name refers to the new species having conspicuous black pigmentation on the body.
Distribution.
Along the southern and western coasts of Korea; Sasuhama and Onagawa Bay, north-eastern Japan.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
