Pareurythoe paupera

Pareurythoe paupera (Grube and Kröyer in Grube, 1857)

( Figures 12–14 View Figure 12 View Figure 13 View Figure 14 )

Amphinome paupera Grube and Kröyer View in CoL in Grube, 1857: 52–53; Salazar-Vallejo and Eibye-Jacobsen 2012

(wrong date; it must be 1857). Eurythoe chilensis Kinberg, 1858: 13 View in CoL ; Kinberg 1867: 90 (species list); Kinberg 1910: 35–36, pl. 12, fig. 9

1930: 28–30, fig. 1. Eurythoe paupera : Ehlers 1901a: 253 (syn.); Ehlers 1901b: 33–34 (syn.). Eurythoe complanata var. paupera : Augener 1922: 172–173. Pareurythoe paupera : Rioja 1941: 682 ( comb. n.); Wesenberg-Lund 1962: 38. Pareurythoe chilensis : Hartman 1948: 45–46, pl. 5, fig. 11; Wesenberg-Lund 1962: 38 (several

Kudenov 1993: 103–104, figs 5, 6 (syn.); Rozbaczylo et al. 2006: 46, fig. 1a–h.

Type material. Southeastern Pacific, Chile. Three syntypes of A. paupera (ZMB 2785) , Valparaíso 1841, H. Kröyer, coll. (date after data in other parts of Annulata Örstediana ) (one complete, breaking three fragments used for redescription; two anterior fragments; brown, variably contracted; caruncle ing median part of chaetiger 3; branchial filaments per chaetiger: 2(6–7), 10 (8–12), 30 (4–6); right podium of chaetiger 19 removed for observation (kept in container); anterior fragments 9.5–21.0 mm 2.5–3.0 mm wide, 30–40 chaetigers).

Syntypes of E. chilensis ( SMNH Type 1265), Valparaíso, Kongliga Svenska Fregatten Eugenies 1851–1853, Sta . 496–505, 8–15 m, mud (most syntypes are fragments; complete specimens measured in ‘Variation’ section).

Additional material. Southeastern Pacific, Chile. Three specimens ( SMNH 178801 View Materials ), Estero Reloncavi Ralún, E off Punta Dirección, Lund University Chile Expedition 1948–49, Sta . M29D ( 41.47°S, 72.32°W

One specimen ( SMNH 178802 View Materials ), Canal Chacao, Peninsula Laqui, N off Punta Corona , Lund University Expedition 1948–49, Sta . M56 ( 41.47°S, 73.32°W), rocky shore, intertidal sediments, 28 February E GoogleMaps . Wesenberg-Lund, leg GoogleMaps . (twisted, brown, mature female, four parapodia previously dissected in body 19 mm long, 3.8 mm wide, 56 chaetigers; caruncle reaches posterior margin of chaetiger 3; eyes 10 times as large as posterior ones).

One specimen ( SMNH 178803 View Materials ), Seno Reloncavi , bay south of Isla Tenglo , Lund University Chile 1948–49, Sta . M60 ( 41.50°S, 72.97°W, sandy beach, 25 March 1949, E. Wesenberg-Lund, leg. (broken pieces, very bent and damaged, not measured).

Four specimens ( SMNH 178807 View Materials ), Canal Chacao, SE off Punta Lenqui , Lund University Chile 1948–49, Sta . M101 ( 41.77°S, 73.65°W), 60–70 m, 5 May 1949, E . Wesenberg-Lund, leg . (brown, contracted; body 15–24 mm long, 2–3 mm wide, 53–54 chaetigers; caruncle reaches half of anterior eyes 3–5 times as large as posterior ones).

Three specimens ( SMNH 178808 View Materials ), Canal Chacao, SE off Punta Lenqui , Lund University Chile 1948–49, Sta . M101 ( 41.77°S, 73.65°W), 60–70 m, 5 May 1949, E . Wesenberg-Lund, leg . (complete ventrally, pale, one with pharynx exposed; body 21–28 mm long, 3.5–4.0 mm wide, 53–74 caruncle reaching half or posterior margin of chaetiger 3; anterior eyes 3–4 times as large as

JOURNAL OF NATURAL HISTORY ventrally, markedly contracted; body 8–9 mm long, 2 mm wide, 40–45 chaetigers; caruncle bent reaching anterior margin of chaetiger 3; eyes indistinct).

Two specimens ( SMNH 178811), Golfo de Ancud, Isla Abtao, N off Punta Barranco, Lund

Chile Expedition 1948–49, Sta. M107A ( 41.78°S, 73.33°W), 60 m, 6 May 1949, E. Wesenberg-Lund (brown; an anterior fragment, and larger specimen without posterior end; the latter with

37 mm long, 3 mm wide, 92 chaetigers; caruncle reaches half of chaetiger 3; posterior seen).

One specimen ( SMNH 178812), Seno Reloncavi, W off Punta Metri, Lund University Chile

1948–49, Sta. M141 ( 41.60°S, 72.80°W), 260 m, polychaete tubes, clay, 14 July 1949, E. Wesenberg-Lund leg. ( 14 mm long, 2 mm wide, 34 chaetigers; caruncle with tip bent upwards, reaching anterior chaetiger 4).

Seventy-seven specimens ( USNM 139202 About USNM ), United States Navy Survey Eltanin, Sta . 960 ( 52.67°S

W to 52.60°S, 74.97°W), 64 m, Blake Trawl, 6 February 1964 (some of different sizes assessed variation).

Six specimens ( ZMB 3642 View Materials ), Chile, Calbuco , Tabón Bajo, H . Plate, coll . (one dried–out, another convoluted; other four specimens complete, variably bent ventrally, chaetae damaged, two with pigmentation; chaetiger and branchial filaments: 2(2–4), 10 (5–24), 30 (2–12), 50 (3–10); body 10.5–

long, 1–4 mm wide, 38–74 chaetigers).

One specimen ( ZMH ANN Vo3237), Tumbes, Talcahuano (no further data; complete, pale, bent left parapodium of chaetiger 24 previously removed (not in container), caruncle reaches median chaetiger 3; body 27 mm long, 3.5 mm wide, 53 chaetigers).

Central South Atlantic, Tristan da Cunha. One specimen ( BMNH 1930.10.8.229), complete, Royal Ship Discovery, Sta . 4 ( 36.92°S, 12.20°W), 40–46 m, rocks, 30 January 1926 (bent ventrally, several previously removed; left parapodia of chaetigers 12 and 32 removed for observation (kept in body 10.5 mm long, 2 mm wide, 45 chaetigers; caruncle reaching anterior margin of chaetiger 4).

Diagnosis

Pareurythoe with caruncle extended along chaetigers 1–3, caruncular depression deep. Anterior eyes

2 times as large as posterior ones. Branchiae from chaetiger 2 with 2–3 filaments. Median segments spurred neurochaetae, largest tine smooth.

Description

Syntype of A. paupera (ZMB 2785) complete, brown, bent ventrally, breaking into three fragments parapodia of chaetigers 1–2, 12, 13 previously removed (not in container); body 28 mm long, 2.5 mm

52 chaetigers.

Anterior region tapered ( Figure 12 View Figure 12 (A)), blunt, prostomium round ( Figure 12 View Figure 12 (B)) with a copepod its apex, other syntypes with prostomium smooth ( Figure 12 View Figure 12 (A,C)); anterior lobe with lateral directed laterally (dorsally in other syntypes), posterior lobe with median antennae; eyes indistinct. antenna central, slightly thinner and longer than laterals, about 1/3 as long as caruncle.

Caruncle sinuous, tapered, blunt, as long as first three chaetigers, reaching median part of chaetiger all syntypes), partially included in a middorsal furrow running along chaetigers 1–3. Pharynx not

Branchiae from chaetiger 2; first branchiae with 2 stems and 4 filaments ( 6–7 in other syntypes), pectinate, progressively increasing in number and size to chaetigers 7–10, thereafter decreasing in number of filaments, with 2 filaments in last chaetigers.

Parapodia biramous ( Figure 12 View Figure 12 (D)). Notopodia reduced, with short low conical lobes; dorsal and cirri tapered, no constricted; dorsal cirri slightly longer than branchiae and ventral cirri.

Chaetae variably damaged, many broken, harpoon notochaetae not seen, probably denticles resulting in acicular chaetae ( Figure 12 View Figure 12 (E)), and spurred notochaetae. Neurochaetae spurred in upper lower bundle portions, longer tines smooth ( Figure 10 View Figure 10 (F)), not denticulate (probably eroded). Additional features

Complete syntype of E. chilensis (SMNH Type 1265), pale ( Figure 14 View Figure 14 (A)), mature female, regenerating parapodium from mid body; body bent ventrally, tapered at both ends, medially wider, tapered

12.5 mm long, 2.3 mm wide, 41 chaetigers.

Anterior region tapered, prostomium round ( Figure 13 View Figure 13 (B)), anterior lobe with lateral antennae upwards, palps slightly longer, directed laterally, posterior lobe with eyes barely visible (distinct in smaller syntype, Figure 14 View Figure 14 (A), anterior eyes 4–5 times as large as posterior ones), median antenna slightly longer than laterals, shorter than caruncle.

Caruncle sinuous, tapered, blunt, as long as first three chaetigers, reaching anterior margin of

( Figure 14 View Figure 14 (B)), partially included in a middorsal furrow running along chaetigers 1–4, less defined in 5. Pharynx not exposed (in a non-type specimen (SMNH 178808), barrel-shaped, smooth, ventrally ent, dorsally with a thick opaque lobe, pharyngeal organ paired).

Branchiae from chaetiger 2, with 2–3 stems and long filaments, looking pectinate; larger arranged in two series, looking pectinate. First branchiae with 2–3 filaments, progressively increasing number and size up to chaetigers 7–10, decreasing in number and size of filaments posteriorly, filaments in far posterior segments.

Parapodia biramous (observed in other syntypes). Notopodia with short low conical lobes; dorsal ventral cirri tapered, irregularly constricted; dorsal cirri slightly longer than branchiae and ventral

Chaetae slightly damaged, many broken, harpoon notochaetae not seen (in SMNH 178802 chaetae, harpoon chaetae with denticles probably eroded); most notochaetae spurred in ( Figure 14 View Figure 14 (D)), and posterior chaetigers ( Figure 12 View Figure 12 (G)). Neurochaetae thicker, spurred in anterior (

(E)) and posterior chaetigers, some with 3–4 denticles along inner surface of longest tine (Figure Acicular chaetae barely expanded along exposed portion.

Posterior region tapered ( Figure 13 View Figure 13 (C)), pygidium blunt conical, anus dorsal or terminal, anal globose, transparent. Oocytes about 80 µm in diameter (also in non– type specimen SMNH 178802)

Variation

The E. chilensis syntypes include two lots and only six complete specimens. They were bent

JOURNAL OF NATURAL HISTORY

(C) Same, chaetiger 10, right parapodium, anterior view. (D) Same, notochaetae. (E) Same, neurochaetae. (F) Chaetiger right parapodium, anterior view. (G) Same, notochaetae. (H) Same, neurochaetae. Scale bars: A, C, F = 0.2 mm; B =

D, E, G, H = 60 µm (authors’ work).

anterior margin of chaetiger 3; in a few from a poorly preserved specimen, the tip of caruncle forwards, and it looks like it is shorter, but once it is bent backwards, it reaches chaetiger 3. Eyes are colourless.

An additional lot (USNM 139202) included specimens 9–22 mm long, 1.5–3.0 mm wide, chaetigers. The caruncle reaches chaetiger 3, at least reaching the anterior region, mostly reaching posterior margin of chaetiger 3. Branchiae were small and showed little variation; there filaments in chaetiger 2, 3–6 in chaetiger 10, 2–3 in chaetiger 30, and 1–2 in chaetiger 50. Eyes mostly colourless.

Remarks

The original description of A. paupera indicates that the caruncle was narrow, entire ( angusta, extending along three segments, and that branchiae start in second segment ( in segment 1mo

These details were confirmed after the study of the syntypes (ZMB 2785). Further, after the study syntypes of P. chilensis (SMNH Type 1265), we confirm they are conspecific.

Amphinome paupera Grube and Kröyer View in CoL in Grube, 1857 was transferred to Pareurythoe View in CoL by Wesenberg-Lund (1962, 38) and newly combined as P. paupera View in CoL . This species was described from Valparaíso, Chile P. chilensis (Kinberg, 1858) View in CoL was also described from the same locality. They are herein regarded as and P. paupera View in CoL has priority over P. chilensis View in CoL .

Augener (1922) made some additional comments and regarded the Juan Fernandez specimens a variety of E. complanata View in CoL . However, it is remarkable that none of the records for E. (or P.) paupera View in CoL any morphological details about why they were identical ( Ehlers 1901a; Chamberlin 1918; Augener Rioja 1941).

Hartman (1948) redescribed the syntypes of P. chilensis and characterised the largest syntype (long, 51 segments). She noted that the posterior eyes were smaller than the anterior ones, that were of similar size, and slightly smaller than palps; its caruncle ‘extends to the posterior end of the setiger; it has a short free lobe that reaches partly over the third setiger’. Branchiae were present chaetiger 2 with 4 filaments, then with 12 filaments in chaetiger 3.

Hartman also noted some differences between P. chilensis and P. californica in the shape of (quadrate in the former, circular in the latter), and in the shape of aciculae (she called them hastate because they are rounded in P. chilensis , truncate in P. californica . However, for this latter feature, (1993, 104) illustrated the different types of chaetae and aciculae for P. chilensis and indicated that

‘are similar in form to those described for other Pareurythoe species’.

Pareurythoe paupera (incl. P. chilensis ) differs from P. californica especially regarding the shape and of the caruncle. In P. paupera it is wider anteriorly, tapering posteriorly, and reaching the anterior chaetiger 4, whereas in P. californica it has a similar width along its length, and reaches the anterior chaetiger 3. There are no differences in prostomial shape or in acicular chaetae.

Pareurythoe chilensis (Kinberg, 1858) View in CoL has been recorded from several localities and the records belong to other different species, as suggested by Hartman (1948, 46). Monro (1930, 28) had a specimen, 10 mm long, and he noted caruncle reached anterior third of chaetiger 4, and branchiae chaetiger 2, matching P. chilensis View in CoL . Some differences in chaetae were pointed out by Monro, such presence of acicular notochaetae and furcate neurochaetae, but he decided to retain the name, about a distribution from southern Chile to Tristan da Cunha. The specimen, however, does not have neurochaetae, and its spurred chaetae match what is shown in P. chilensis View in CoL specimens, such that this regarded as conspecific with P. chilensis View in CoL . He also illustrated furcate neurochaetae, but all that was two parapodia included spurred ones. Other records requiring confirmation are those by Horst ( Indonesia, and Day (1967) for South Africa.

Distribution

This species has been recorded from California to Chile, but these records might include more than species; it was originally described from the Magellan Strait, and it is also present in the Central shallow-water sandy or mixed bottoms.