Iphione henshawi Pettibone, 1986

Salazar-Vallejo, Sergio I., Piotrowski, Christina N. & Paulay, Gustav, 2024, Revision of Iphione Kinberg, 1856 (Annelida, Aphroditiformia, Iphionidae), Zootaxa 5548 (1), pp. 1-84 : 35-39

Iphione henshawi Pettibone, 1986

Figs 3A–C , 10 , 11 , 36

Iphione henshawi Pettibone, 1986: 21–23 , Figs. 8 , 9 ; Wehe 2006: 62, Fig. 7a–h .

Type material. Hawaii. Holotype ( USNM 81936 ), Hilo , low water, May 1904, H. Henshaw, coll. (holotype in worse condition than paratype; body pale, without elytra; right parapodia of chaetigers 2, 9, 12–15 previously removed (kept in container); prostomium with eyes black, anterior eyes in lateral projections, very close to posterior eyes; elytra with epibionts, variably eroded, dark yellow, with one to a few thin blackish oblique lines, some without lines; macrotubercles small, in median elytra about 10 rows; cirrigerous segments with dorsal cirrophores without projected basal tubercle; body 29 mm long, 16 mm wide, 29 chaetigers) . Paratype ( USNM 5439 ), USFCS Albatross, Sta. 3999 (21°56’20” N, 159°42’45” W), Kaulakahi Channel , between Kauai and Nihau Islands, 13–271 m, 16 Jun. 1902 (used for redescription) .

Additional material. Hawaii. One specimen ( BPBM R481 ) , Oahu, Makapuu Point , 1 Jul. 1955, depth not given, C.E Cutress, coll. (body 35 mm long, 17 mm wide, 28 chaetigers; data used for variation). One specimen ( CASIZ 10057 ) , Hawaii, Hilo , July 1915, E.M. Erhorn, coll. (dark brown elytra, moderately covered in debris, with narrow oblique dark band submedially, lighter pigment at lateral margin, 10 diffuse rows of small macrotubercles, progressively smaller posteriorly, prostomium damaged and retracted into anterior segments; body 29 mm long, 19 mm wide, 29 chaetigers). One specimen ( CAS 10075 ) Honolulu, Portloch ( Portlock ), 9 m, from Steinhart Aquarium , 26 Nov. 1971 (first four elytral pairs removed; right parapodium of chaetiger 13 dissected, basal lobe of cirrophore brownish (kept in container); elytra dark brown with a thin, oblique blackish line towards inner region; basal tubercle of dorsal cirri enlarger, elongate, blackish dorsally; prostomium distorted by eversion of pharynx; jaws with 3 denticles, a fourth barely visible; neurochaetal rows of denticles partially eroded; body 37 mm long, 23 mm wide, 28 chaetigers). One specimen ( LACM 7461 ) , Maui, Lahaina District, Kapalua , Kapalua Bay (20°59.98’ N, 156°40.06’ W), 3.6–4.5 m, under large pieces of coral rubble, 18 Jun. 2013, G. Hendler, coll. (elytra brownish, with epibionts, oblique longitudinal line blackish, macrotubercles small, in 10 rows, progressively smaller posteriorly; cirrigerous segments with basal tubercle of dorsal cirrophore projected; body 37 mm long, 22 mm wide, 29 chaetigers). One specimen ( LACM AHF 12813 ) , Maui , 1967, J. & D. Soulé, coll. (bent ventrally; some elytra previously removed; elytra dirty yellowish, with epibionts, oblique longitudinal lines better defined in posterior elytra, with 6–7 rows of macrotubercles; cirrigerous segments with basal tubercle of dorsal cirrophore projected; body 21 mm long, 14 mm wide, 29 chaetigers). One specimen ( UF 152 ) , off Cook Point (19°28’36.9001” N, 155°56’23.5” W), 5–10 m, under rocks, 4 Nov. 1997, G. Paulay, coll. (right elytron 7 removed, with a marginal bryozoan with a darker core and transparent cortex resembling a subdistal round dark spots in some elytra; with 12 rows of macrotubercles; basal tubercle of dorsal cirrophore pale; neurochaetae with 36–54 transverse rows of denticles; body 42 mm long, 21 mm wide, 29 chaetigers) .

Red Sea. One specimen ( UF 3666 ), Saudi Arabia, off Thuwai , Shark Reef (22°25’37.2” N, 38°59’45.6” E), 0–20 m, offshore reef, A. Anker, P. Norby, J. Moore & J. Bouwmeester, coll. (complete, left elytron 7 previously removed; elytra yellowish with 1–2 oblique longitudinal black bands; macrotubercles small in 8–9 rows; cirrigerous segments with basal tubercle of dorsal cirrophore not projected; body 23 mm long, 12 mm wide, 29 chaetigers) .

South Africa. Three specimens ( ZMA V2580), Delagoa Bay , near Johaca Island, Jul. 1935, C.J. van der Horst, coll. (one specimen with most elytra and three median right parapodia previously removed (in separate vial); two other ones markedly bent ventrally; elytra fimbriae long, including some posterior margins parts, especially in regenerating areas; macrotubercles small, in two rows; basal tubercle of dorsal cirrophores projected; neurochaetae unidentate, slightly tapered; non-bent specimen 29 mm long, 14.5 mm wide, 29 chaetigers) .

Madagascar. One specimen ( MNHN A 274-33 ), 1901–1911, M. Ferlus, coll. (no further data; fixed in ethanol, bent ventrally, regenerating posterior region; most elytra detaching from body; elytra yellowish with 7–8 rows of microtubercles; body 22 mm long, 13 mm wide, 29 chaetigers) . One specimen ( MNHN IA 2015-162 ), Cruise Madagascar 2010, RV Miriky, Sta. DW 3238 (14°29´S, 47°27´E), 139– 48 m, 6 Jul. 2009, L. Albenga et al., coll. (bent ventrally; elytra yellowish, with few epibionts, macrotubercles small, conical, in 10 rows; cirrigerous segments with basal tubercle of dorsal cirrophore projected; body 30 mm long, 19 mm wide, 29 chaetigers) .

Mascarene Islands, La Réunion. One specimen ( UF 647 ), Saint-Paul , Trou d’eau, Passe de l’hermitage (- 21°06’06.0012” S, 55°14’36.9996” E), 9–12 m, fore reef, under rock, 8 Aug. 2007, H. Bruggemann, N. Hubert, F. Michonneau & G. Paulay, coll. (right parapodia of chaetigers 15–17 removed for molecular analysis; elytra golden with about 10 rows of macrotubercles, elytra pairs 1–6 with indistinct black spots, elytra pairs 7–10 with 1–2 oblique thin blackish lines, elytra pairs 11–13 with a single line; neurochaetae with 20–28 transverse rows of denticles; body 33 mm long, 12 mm wide, 28 chaetigers) . One specimen ( UF 657 ), Saint-Leu , Sec Jaune (21°09’19.8” S, 55°16’52.0201” E), 10–19 m, rocky slope, basalt blocks, 17 Aug. 2017, H. Bruggemann, N. Hubert & F. Michonneau, coll. (right parapodia of chaetigers 13, 14 removed for molecular analysis; basal tubercle of dorsal cirrophore brownish, a discontinuous spot extended dorsally, base of cirrostyle with a short, slightly longer than wide brownish band; neurochaetae with 40–50 transverse rows of denticles; elytra dark golden, with an oblique black line along elytra pairs 5–13, double in elytra pairs 8–12, right elytron 6 removed, with 12 transverse rows of macrotubercles; ceratophores of lateral antenna and facial tubercle blackish; body 46 mm long, 23 mm wide, 28 chaetigers) .

Sultanate of Oman. One specimen ( UF 10473 ), Dhofar Governate, Mirbat, Tinawelli ,ARMS site 1 (16°56’02.4” N, 54°47’06.0” E), 24 m, rocky and sandy bottom, 24 Jan. 2022, G. Paulay, C. Meyer, S. Maslakova, M. Casterelli & F. Berzoni, coll. (slightly bent ventrally; right parapodia of chaetigers 13–20 previously removed; elytra yellowish, with an oblique longitudinal black band, and a few other ill-defined bands; 9–10 rows of tiny macrotubercles, slightly smaller towards posterior margin; cirrigerous segments with basal tubercle of dorsal cirrophores projected; body 26 mm long, 16 mm wide, 29 chaetigers) .

Maldives. One specimen ( UF 4069 ), Blue Cove , 1.5 km NNE of Magoodhoo Island (03°05’37.788” N, 72°57’59.4” E), 10–28 m, high coral cover, slope, 6 May 2014, J Moore, coll. (juvenile; left elytron 7 and left parapodium of chaetiger 11 removed for molecular analysis; right elytron 7 and left parapodium of chaetiger 13 removed for observation (kept in container); elytra golden with a series of blackish spots forming two longitudinal discontinuous bands along body; elytron with 3–4 rows of short conical macrotubercles, each with margins rough, with one median spine and 2–3 distal curved spines; basal tubercle of dorsal cirrophore pale; neurochaetae with 14–32 transverse rows of denticles; body 12 mm long, 6 mm wide, 28 chaetigers) .

Japan. One specimen ( UF 383 ), Okinawa, Ie Island, NE end of Island, area around Crevice and Daidokutsu Cave (26°43’28.4401” N, 127°49’53.94” E), 15–18 m, outer reef slope, under rocks, 7 Jul. 2004, G. Paulay & Kinjo, coll. (slightly bent ventrally; first left and sixth right elytra; anterior appendages blackish; elytra brownish, anterior pairs 1–5 almost without spots, following ones with 1–3 oblique blackish bands, thinner and discontinuous or wider and solid; elytra with 12–14 rows of macrotubercles; neurochaetae with 30–42 transverse rows of denticles; body 31 mm long, 18 mm wide, 28 chaetigers) . Three specimens ( USNM 100444 ), Okinawa, Horshoe Cliffs, 1 km WNW off Omna Village (26°30’00” N, 127°50’54” E), 54.9 m, 23 May, 25 Sep. 1981, R.F. Bolland, coll. (anterior appendages blackish; eyes black, anterior and posterior eyes very close to each other laterally; one specimen straight, others bent ventrally; several elytra and parapodia previously removed (kept in container), one with a anteroventral previously made dissection for observing jaws; macrotubercles abundant, in elytra with fewer rows, slightly larger than in Hawaiian specimens; basal pharynx area blackish; jaws with tips brownish, and 3 accessory denticles; body 25–32 mm long, 13–16 mm wide, 28–29 chaetigers) .

Mariana Islands, Guam. One specimen ( UF 21 ), Sella Bay (13°30’00” N, 144°48’00” E), 5–10 m, patch reef, under hanging Leptoseris coral, 22 Aug. 1984, G. Paulay, coll. (bent ventrally; right elytra 6 and 7 previously removed (only one left in container), left parapodium of chaetiger 14 previously removed (not in container); left parapodium of chaetiger 11 removed for observation (kept in container), basal tubercle of dorsal cirrophore without dark pigmentation; neurochaetae with 42–50 transverse rows of denticles; lateral antennae and facial tubercle pale; body 50 mm long, 22 mm wide, 28 chaetigers) .

Australia. One specimen ( AM W37302 ), Woodside Kimberley Survey 2010, Sta. 34, 12 m, 16 Oct. 2010, A. Hosie, coll. (bent ventrally, elytra yellowish with a blackish oblique band, some with white epibionts (bryozoans, ascidians, algae); some posterior elytra previously removed; elytra with two rows of low conical macrotubercles; basal tubercle of dorsal cirrophores projected; neurochaetae unidentate; body 12 mm long, 6.5 mm wide, 28 chaetigers) .

Papua New Guinea. One specimen ( UF 3989 ), Madang Province, Madang, University Road (05°13’46.4412” S, 145°47’58.0344” E), 15 m, 12 Nov. 2012, B. Faure, R. Ibik, P.-H. Kuo, coll. (non-distorted specimen; first left elytron lost, right one detaching; macrotubercles arranged in 9 rows, many tubercles broken; left parapodium of chaetiger 11 removed for observation (both kept in container); basal tubercle of dorsal cirrophore tapered, not projected; 29 mm long, 14 mm wide, 28 chaetigers) .

Kiribati, Line Islands. One specimen ( UF592 ), KiritmatiAtoll,under rocks, 21Aug.2005, G. Paulay, coll.(elytra yellowish with a thin oblique, longitudinal blackish band; basal tubercle without dark pigmentation; neurochaetae with 40–50 transverse rows of denticles, mostly eroded; body 45 mm long, 21 mm wide, 29 chaetigers) .

French Polynesia, Society Islands. One specimen ( UF 918 ), Tahiti Island, Motu-Uta (17°36’00” S, 149°24’00” W), 21 m, 1 Nov. 2008, P. Bacchet, coll. (juvenile, bent ventrally, right elytron 8 removed for observation (kept in container) with 4–5 rows of low macrotubercles; parapodia not removed; 14 mm long, 6.5 mm wide, 28 chaetigers) .

Diagnosis. Iphione with median antenna reduced to nuchal papilla; elytra fimbriate; macrotubercles conical, slightly longer than wide, in 2–11 rows, first row with macrotubercles slightly larger than those in other rows; cirrigerous segments with dorsal cirrophores with basal tubercle indistinct; neurochaetae unidentate.

Description. Paratype (USNM 5439) bent ventrally, 41 mm long, 29 mm wide, 29 chaetigers; several elytra previously removed, remaining ones with long fimbriae and abundant epibionts (hydroids, sponges, three median parapodia previously dissected (in container); mature male, testes occupying most of coelom space. Body wall pale dorsally and ventrally, elytra brownish.

Elytra brownish to bronze, with fimbriae ( Fig. 10B , inset), 1–2 thin blackish bands in some posterior elytra; macrotubercles short, round, slightly projected into single spine, of similar size, with long blunt fragile spines ( Fig. 10D , inset), arranged in 5–18 rows, occupying 1/5–1/3 elytral surface, more widespread in smaller elytra.

Prostomium wider than long, with a shallow longitudinal depression restricted to anterior prostomial margin. Anterior lobes projected into ceratophores, longer than prostomium, ceratostyles lost. Palps previously removed, size proportion to antennae unknown. Eyes black, positioned in posterior prostomial half ( Fig. 10A ), anterior eyes projected laterally, as large as posterior eyes; anterior and posterior eyes along the same side very close to each other, 1/3 as far as distance between posterior eyes. Nuchal papilla not visible dorsally, covered by nuchal hood, slightly longer than wide.

Tentacular segment dorsally reduced, cirri and chaetae not seen. Facial tubercle visible dorsally, pale.

Segments 2–4 directed anteriorly. Second segment visible dorsally, with a projected nuchal lappet, lobate, longer than wide, completely covering nuchal papilla. Ventral buccal cirri inserted ventrally, slightly longer than following ventral cirri, extended beyond chaetal tips. From segment 3, one pair of globular, separate dorsal nodules per segment, barely visible after compression. Segments 2–3 with finer neurochaetae, barely swollen subdistally, with a longer region covered by series of transverse denticulations.

Median cirrigerous segments with dorsal cirri surpassing chaetal tips ( Fig. 10E ), shape resembling lateral antennae; dorsal cirrophore smooth, without basal tubercle. Notochaetae brownish, very abundant, delicate capillaries with series of transverse funnel-shaped spinose rows, tips bare. Neuropodia with neuracicular lobe 3 times longer than wide, blunt; neurochaetal lobe with small globular papillae. Neurochaetae thick, abundant, basally smooth, subdistally swollen, with series of fine denticulations along swollen region, tips falcate, sharp ( Fig. 10F, G ).

Anus dorsal, positioned between elytral pairs 12 and 13.

Variation. Pharynx features ( Fig. 3A–C ) were indicated above. A non-type specimen (BPBM R481) is a mature female, slightly bent ventrally, pharynx fully exposed ( Fig. 3 , explained above in anatomy); prostomium oval, pale, lateral antennae ceratophores brownish ( Fig. 15A ); palps almost twice longer than antennae, darker from medial region to tips; eyes blackish, of similar size, anterior eyes in small protuberances at the widest prostomial surface, about the middle of prostomium; median antenna reduced to small lobe; nuchal lappet semicircular; first four pairs of elytra removed, two left parapodia of median chaetigers dissected (retained in container); elytra dark brown with fimbriae elongate, with spinous lobe and long, blunt spines ( Fig. 11C ); macrotubercles conical to irregular, arranged in 15–20 rows, each often with a main short, straight spine and 1–4 lateral curved, blunt long spines ( Fig. 11D ); dorsal cirrophore lobe conical, tapered, without ventral projections ( Fig. 11E ); oocytes of about 100 μm in diameter.

The additional specimens were 12–50 mm long, 6–23 mm wide. The number of rows of macrotubercles is roughly size-dependent, but it can be modified if the tubercles are small, there can be more rows even in specimens of similar size.

Remarks. Iphione henshawi Pettibone, 1986 was described with two specimens being indicated as 29–41 mm in length. The holotype was the largest specimen (described as 41 mm long, it is 29 mm long) and was collected in the low intertidal; its median elytra were illustrated as having rows of small macrotubercles, whereas the paratype was smaller (29 mm long; actually of the same size) and was sampled in a haul along 13–271 m, and its median elytra have about 10 rows of small macrotubercles. The confusion of the size and the number of rows of macrotubercles were misleading, because it implied that at least regarding the number of rows of macrotubercles, they are not size-dependent after these two specimens. However, they are of the same length and have a similar number of rows of macrotubercles. In both specimens, the anterior eyes are in small lateral projections, very close to posterior eyes laterally, and dorsal cirrophores have barely projected basal tubercles. Two different non-type specimens were COI-sequenced: one from Papua New Guinea (UF 3989) is 29 mm long and has about 10 rows of macrotubercles, the other one is from the Maldives (UF 4069) being 12 mm long and has 4–5 rows of macrotubercles; both have barely developed basal tubercles in dorsal cirrophores. They fall very close to each other in the dendrogram ( Fig. 36 ); consequently, the number of rows of macrotubercles is size dependent, and not a diagnostic feature for I. henshawi .

The specimen recorded by Wehe (2006) from the Red Sea was 12 mm long, and it has anterior and posterior eyes very close in lateral view. The Red Sea specimen shows some differences from the larger Hawaiian specimens. For example, the Red Sea specimen has no nuchal flap or lappet, and its first dorsal tubercles are poorly defined, elytra have 2–3 rows of macrotubercles whereas there are 3–10 in Hawaiian specimens, and neurochaetae have fewer rows of spines (11 were illustrated) whereas there are 18–33 in Hawaiian specimens. The difference in notochaetal pigmentation and the number of rows of macrotubercles are size-dependent, and consequently, Red Sea specimens are herein regarded as conspecific .

Iphione henshawi Pettibone, 1986 belongs in the group of species having fimbriate elytra. As indicated in the key above, it differs from all other species in the group by having small macrotubercles, arranged in 2–10 or more rows, and fimbriae well defined.

Iphione henshawi is sister to I. malifera in the COI phylogeny ( Fig. 36 ).

Distribution. Red Sea to South Africa, east to the Hawaiian, Line, and Society Islands, on reefs and rocky or mixed bottoms in shallow water to shelf depths (0–271 m).

Figures

FIGURE 3. Pharynx features. A. Iphione henshawi Pettibone, 1986, non-type specimen (BPBM R481), anterior end, pharynx exposed, dorsal view. B. Same, ventral view. C. Same, frontal view of pharynx (numbers indicate papillae). D. Same, left lateral view. E. Iphione muricata (Savigny in Lamarck, 1818), restricted, non-type specimens (UF 411), smaller specimen (9 mm wide), pharynx, frontal view (numbers indicate upper papillae). F. Another, larger specimen (16 mm wide), pharynx, frontal view (numbers indicate upper papillae). Scale bars: A, B, 1.3 mm; C, 0.9 mm; D, 0.7 mm; E, 0.3 mm; F, 0.6 mm.

FIGURE 7. Iphione fimbriata de Quatrefages, 1866, reinstated, holotype (MNHN POLY TYPE 325). A.Anterior region, dorsal view. B. Left elytron 7, after brushing off sediment, dorsal view (inset: close up of dirty to clean fimbriae). C. Chaetiger 16, left parapodium, posterior view. D. Chaetiger 12, left parapodium, after removal of notochaetae and Methyl green stain. E. Same, upper notochaetae. F. Same, lower neurochaetae. Scale bars: A, 1.7 mm; B, 1 mm; C, 0.6 mm; D, 0.5 mm; E, 170 µm; F, 200 µm.

FIGURE 8. Iphione fimbriata de Quatrefages, 1866, reinstated, paratype of I. fustis Hoagland, 1920 (USNM 18969).A.Anterior end, dorsal view, after Methyl green staining. B. Anterior elytra, above: right elytron from chaetiger 2; below: left elytron from chaetiger 4. C. Left elytron from median chaetiger, dorsal view (insets: fimbriae, and smaller marginal spines). D. Chaetiger 14, left parapodium, posterior view after Methyl green staining. E. Same, upper and medial neurochaetae. F. Same, medial and lower neurochaetae. Scale bars: A, 1.1 mm, B, 1 mm; C, 2 mm; D, 0.6 mm; E, 100 μm; F, 80 μm.

FIGURE 9. Iphione fimbriata de Quatrefages, 1866, reinstated, paratype of I. fustis Hoagland, 1920 paratype (USNM 18968), elytra previously removed, seen from above.A. Second right elytron. B. Third right elytron. C. Fourth right elytron. D. Fifth left elytron. E. Sixt left elytron. F. Non-type specimen (USNM 81972), anterior end, dorsal view. G. Another specimen from same lot, pharynx previously dissected, seen from inside, depressed by glass slide. Scale bars: A, 0.7 mm; B, G, 0.8 mm; C, 1.1 mm; D, E, 0.6 mm, F, 1.3 mm.

FIGURE 10. Iphione henshawi Pettibone, 1986, paratype (USNM 5439). A. Anterior end, dorsal view. B. First elytron, dorsal view (inset: close-up of fimbriae). C. Right anterior elytron, with some calcareous epibionts. D. Left posterior elytron (inset: close-up of macrotubercles and spines). E. Cirrigerous right parapodium, posterior view. F. Same, neurochaetae of mid-bundle. G. Same, neurochaetae of lower bundle. Scale bars: A, 1.8 mm; B, C, 1.4 mm; D, 2.6 mm; E, 1.1 mm; F, G, 0.7 mm.

FIGURE 11. Iphione henshawi Pettibone, 1986, non-type specimen (BPBM R481). A. Anterior end, dorsal view (elytra 1–3 removed). B. Left elytra 1–3, dorsal view. C. Elytron 3, close-up of fimbriae, some macrotubercles in the lower area. D. Same, close-up of macrotubercles. E. Cirrigerous left parapodium of median segment, posterior view. Scale bars: A, 0.8 mm; B, 1.4 mm; C, D, 0.3 mm; E, 0.5 mm.

FIGURE 15. Iphione coriolis Hanley & Burke, 1991, holotype (MNHN TYPE 574). A. Anterior end, dorsal view. B. Right elytron from median chaetiger. C. Left elytron from postmedian chaetiger. D. Chaetiger 12, right parapodium, posterior view. Scale bars: A, B, 0.4 mm; C, 0.5 mm; D, 0.2 mm.

FIGURE 36. Maximum Likelihood phylogeny of Iphione species with localities and catalog numbers. Numbers above branches are bootstrap support (>70 only) (PNG: Papua New Guinea) (modified after Piotrowski et al. 2024).