Hesione genetta Grube 1867
Creators: name: Salazar-Vallejo, Sergio I.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Phyllodocida
Hesionidae
Hesione
Hesione genetta

description: Hesione genetta Grube, 1867
(Figs 15, 16)
Hesione genetta Grube, 1867: 65, 66; 1878: 104. — Chamberlin 1919: 186-188, pl. 22, figs 7, 8. — Treadwell 1926: 189. — Monro 1931: 10, fig. 5; 1939: 392. — Augener 1933b: 224, 225, fig. 3A- B. — Reish 1968: 212. — Wu et al. 1975: 75, 76. — Uchida 2011: 3, fig. 1.
Hesione pantherina – Fauvel 1953c: 174 (non Risso 1826).
Hesione splendida – Augener 1927a: 131. — Ehlers 1920: 25, 26. — Gibbs 1971: 139; 1972: 204 (partim, non Savigny in Lamarck, 1818).
TYPE MATERIAL. — Samoa. ‘ Syntypes’ (see remarks): 1 specimen, ZMH-P 1283, identified by Grube, no further data [24 mm long, 4 mm wide; body macerated, whitish, anterior and posterior ends damaged; neuraciculae blackish, tapered; acicular lobe double, upper tine slightly longer than ventral one; neurochaetal blades with subdistal tooth as large as distal one, guard approaching subdistal tooth]. — 3 specimens, ZMH-P 1284, Upolu (13°55’S, 171°45’W), identified by Grube, no further data [17-46 mm long, 2-7 mm wide; complete, larger one macerated, with brownish round dots dorsally, smaller specimens dehydrated, with a wide brownish dorsal band in chaetiger 1, and another one with several irregular dorsal transverse bands along several anterior chaetigers, including chaetiger 1; antennae long, digitate, 6-7 times as long as wide; eyes brownish, anterior ones twice as large as posterior ones; neuraciculae blackish, tapered; acicular lobe double, blunt, digitate, upper tine slightly longer than lower one; neurochaetal blades with subdistal tooth as large as distal one; guard approaching subdistal tooth].
ADDITIONAL MATERIAL. — Samoa. 1 specimen, BMNH 1921.5.1.1070, W. C. McIntosh, donor, no further data [macerated, dorsal brownish dots barely visible; body 48 mm long, 6 mm wide; left paraodium of chaetiger 4, and right parapodium of chaetiger 8 previously removed; chaetal lobes invaginated; acicular lobes double, upper tine twice thicker than lower one]. — 1 specimen, MNHN-IA-PNT91b (formerly jar 70), Maru, 1887 (37), no further data [57 mm long, 7 mm wide; colorless; prostomium invaginated; acicular lobes double, long, tapered]. — 2 specimens, MCZ 46394, West Reef, 26.X.1898, no further data [17-23 mm long, 2-3 mm wide; remains of a diffuse broad band on chaetiger 1; acicular lobes double; most chaetae broken]. — 1 specimen, UF 81, used for Redescription, Tutuila Island (-14.2885, -170.68066; 14°17’18.6000”S, 170°40’50.3760”W), reef flat, under rubble, 19.X.2002, V. Bonito coll.
Palau. 1 specimen, UF 44, Malakal Sewer Outfall, under rocks, 2 m depth, 26.VII.1999, G. Paulay coll. [body complete, pigmentation with abundant small dark brown spots throughout the body, with the exception of an anterior dorsal colorless collar (wide transverse band) along chaetiger 2, and an oval, dorsal as wide as long colorless spot on the central region of chaetiger 1; pigmentation extended ventrally in a few anterior and posterior chaetigers; pygidium with a similar pigmentation; dorsal cirri basally smooth, ventral cirri articulated, usually longer than chaetal lobe; acicular lobe double, upper tyne about twice as long as lower one; neurochaetal blades progressively shorter ventrally, subapical tooth large (as large as apical one), guard reaching subapical tooth].
Japan. 1 specimen, MCZ 84733, Ryukyu Islands, Seragaki Beach, 1.3 km ENE Maeki-zaki, Okinawa (26°30.4’N, 127°52.6’E), 3 m depth, coral rubble, 17.II.1989, R. F. Bolland coll. [32 mm long, 5 mm wide; macerated, with some dark pigment bands or spots barely visible along some anterior chaetigers; body soft depressed, pharynx fully exposed; parapodia invaginated; eyes almost colorless, antennae digitate, as long as interocular distance; dorsal cirri macerated; acicular lobe double, digitate to truncate triangular, of about the same length; parapodia not removed to avoid further damage; pygidium with anus broken].
Mariana Islands. 2 specimens, UF 34, Guam Island, Pago Bay, reef flat, under rocks, 0-0.5 m depth, 2.VII.2000, G. Paulay coll. [20.0- 20.5 mm long, 2.0- 2.5 mm wide; pigmentation pattern visible, smaller specimen darker, more dehydrated; pharynx not exposed; antennae as long as interocular distance]. — 1 specimen, UF 40, Guam Island, Pago Bay (13.5, 144.8; 13°30’00”N, 144°48’00”E), reef front, under rock, 1-5 m depth, 15.V.1997, G. Paulay coll. [45 mm long, 4.5 mm wide; pigmentation pattern almost completely gone, dorsal transverse bands incomplete, better defined along chaetigers 1-5; antennae longer than interocular distance; acicular lobe double, upper tine 3 times longer than lower one; neurochaetal blades bidentate, subdistal tooth as thick or thicker than distal one; guard approaching subdistal tooth; body wider posteriorly]. — 1 specimen, UF 47, Guam Island, Pago Bay (13.5, 144.8; 13°30’00”N, 144°48’00”E), dry intertidal, under rock, 9.VIII.1995, L. Ward coll. [29 mm long, 3 mm wide; body bent backwards; antennae as long as interocular distance; anterior eyes slightly larger than posterior ones; first chaetiger with a thick dark brown, irregular transverse band, missing in chaetiger 2, progressively paler, discontinuous from chaetiger 3, reduced to a half-moon middorsal spot in posterior chaetigers; acicular lobe double, upper tine larger than lower one]. — 1 specimen, UF 52, Guam Island, Orote (13.4165, 144.650166; 13°24’59.4”N, 144°39’00.5976”E), 1-9 m depth, 11.III.2000, L. Kirkendale coll. [26 mm long, 3 mm wide; slightly bent laterally; one posterior left parapodium removed; pigmentation pattern with a thick irregular transverse band on chaetiger 1, less defined on chaetigers 2-3, thereafter paler progressively loosing definition; antennae longer than interocular distance; anterior eyes twice as large as posterior ones; median chaetigers with dorsal cirri as long as body width, without parapodia]. — 1 specimen, UF 92, Guam Island, N Pago Bay (13.42453, 144.78581; 13°25’28.3080”N, 144°47’08.9160”E), 0-1 m depth, 30.IV.2003, G. Paulay coll. [24 mm long, 3 mm wide; body bent laterally, median right parapodia removed for molecular analysis; pigmentation pattern paler posteriorly, transverse bands better defined along chaetigers 1-7, thinner, less defined in following chaetigers; antennae as long as interocular distance; anterior eyes slightly larger than posterior ones; acicular lobe double, tines blunt, upper one slightly longer than lower one]. — 1 specimen, UF 95, Guam Island, N Pago Bay (13.42453, 144.78581; 13°25’28.3080”N, 144°47’08.9160”E), 0-1 m, 30.IV.2003, G. Paulay coll. [34 mm long, 4 mm wide; body laterally bent, thicker posteriorly; ovaries exposed after removal of parapodia for molecular analysis; pigmentation pattern visible, darker anteriorly, paler posteriorly]. — 1 specimen, UF 100, Guam Island, Hagatna Bay (13.5, 144.8; 13°30’00”N, 144°48’00”E), E Side, outer reef flat, intertidal under rocks, 30.XI.2002, G. Paulay coll. [27 mm long, 2.5 mm wide; pigmentation pattern more intense along anterior chaetigers, a thick irregular band on chaetiger 1, tentacular cirri pale brown; pharynx exposed, dorsal papilla not seen; antennae longer than interocular distance; posterior right parapodia removed for molecular analysis; gonads thick, round, visible through dissected area; body partially dehydrated, stiff, bent dorsally]. — 1 specimen, UF 699, Guam Island, Hagatna, S of Adalupe Island (13.479906, 144.726632; 13°28’47.6616”N, 144°43’35.8752”E), fore reef, 0-1 m depth, 9.II.2008, F. Michonneau coll. [22 mm long, 3 mm wide; body bent ventrally, with some posterior left parapodia removed for molecular analysis; pigmentation pattern well defined, a thick irregular transverse band on chaetiger 1, following chaetigers with thinner, paler, irregular transverse bands; pharynx fully everted, dorsal papilla pale, as long as wide; antennae longer than interocular distance; anterior eyes twice as large as posterior ones; median chaetigers with dorsal cirri longer than body width, including parapodia; acicular lobe double, upper tine larger than lower one]. — 1 specimen, UF 1741, Guam Island, 100 m W of University of Guam Marine Lab (13.5, 144.8; 13°30’00”N, 144°48’00”E), shallow bay, backreef, algae & cyanobacteria, un- der big rocks among rubble/sand, 0.5 - 1.0 m depth, 22.VI.2010, A. Anker coll. [30 mm long, 4.5 mm wide, pigmentation pattern visible; body twisted, anterior end directed ventrally; prostomial features as those seen in other specimens].
Marshall Islands. 4 specimens, LACM 10154, Rangelap Atoll, Bokuyarito Island, shore, 28.VII.1946, J. Rachita & F. C. Fresenhinne coll. [27-36 mm long, 5-6 mm wide; macerated, pigmentation remaining along several anterior chaetigers]. — 1 specimen, LACM 10155, Bikini Atoll, V.1946, M. W. Johnson coll. [26 mm long, 2 mm wide; partially dehydrated; pigmentation mostly faded off, restricted to an irregular pale brown transverse band on chaetiger 1; gonads extended from chaetiger 8 backwards, 3-4 lobulate masses per segment, more thightly packed in chaetigers 13-16]. — 1 specimen, LACM 10157, Rangelap Atoll, Burok Island, intertidal coral, 18.VII.1946, M. W. Johnson coll. [24 mm long, 2.8 mm wide; macerated, pigmentation now restricted to a pale brown transverse band on chaetiger 1; pharynx partially everted]. — 1 specimen, USNM 23948, Ralik Chain, Enewetak Atoll, Rujoru Island, 2.VI.1946, J. Morrison coll. [24 mm long, 3.5 mm wide; splendid specimen, pigmentation still visible, irregular transverse bands on all chaetigers, darker and larger anteriorly, reducing their size and intensity posteriorly; individual spots not visible]. — 1 specimen, USNM 29890, Ralik Chain, Enewetak Atoll, Bogombogo Island, ocean side, intertidal, 2.VII.1957, D. J. Reish coll. [23.5 mm long, 3 mm wide; slightly damaged specimen; pigmentation with transverse irregular bands almost along the whole dorsum; acicular lobe double, upper one 0.5-1.0 times longer than lower one, not subequal]. — 1 specimen, USNM 118617, Bikini Atoll, Enyu Island, ocean side, Sta. E-110, 6.IX.1956, D. J. Reish coll. [43 mm long, 5 mm wide; splendid specimen, with a dark brown maculated pattern along the body, forming transverse irregular bands on chaetigers 1, 3-6, thereafter spots diminishing in size and darkness]. — 1 specimen, UF 702, Majuro Atoll, Kolalen (7.15792, 171.21438; 07°09’28.5120”N, 171°12’51.7680”E), channel (E end of the island), intertidal rocks and pools, 8.IV.2008, F. Michonneau & K. Sun coll. [37 mm long, 3 mm wide; body with irregular, discontinuous transverse dorsal bands, better defined along anterior chaetigers; body bent laterally, posterior right parapodia removed for molecular analysis; pharynx partially exposed, dorsal papilla visible].
French Polynesia. 1 specimen, BMNH 1941.4.4.683, Tahiti, Crossland Pacific Cruise 1923-1924, among corals, 10.VII.1925, C. Crossland coll. [distorted, bent laterally, abundant, dorsal brownish dots and middorsal larger spots well-defined; body 44 mm long, 4.5 mm wide; parapodia not dissected; dorsal cirri as long as body width (excluding parapodia); acicular lobes double, upper tine slightly wider and longer than lower one]. — 1 specimen, BMNH 1941.4.4.684, Tahiti, Faa, Crossland Pacific Cruise 1923-1924, barrier edge, 1.VI.1926, C. Crossland coll. [distorted, anterior end twisted laterally, posterior region bent ventrally, dorsal brownish dots and a few transverse bands barely visible; body 40 mm long, 6 mm wide; right parapodium of chaetiger 5 previously removed; chaetal lobes invaginated; acicular lobes double, tines of similar width, upper tine slightly longer than lower one]. — 3 specimens, MNHN-IA-PNT91c (formerly jar 70), Tahiti, 1952, R. Ranson coll. [27-28 mm long, 4 mm wide; 2 specimens with well-defined irregular transverse brownish bands and round spots throughout body; acicular lobe double]. — 1 specimen, UF 24, Tuamotu Islands, Rangiroa Atoll, Avatoru Motu, off Far W Hoa (-14.98333, -147.61666; 14°58’59.9880”S, 147°36’59.9760”W), outer reef flat, and reef crest, nestled in crevices in reef rock, 26.X.2001, G. Paulay coll. [45 mm long, 4 mm wide; complete; pigmentation pattern as typical; pharynx not everted; antennae longer than intraocular distance; acicular lobes invaginated in anterior chaetigers, clearly double in median chaetigers, but sometimes the upper one shortened or more contracted then the lower one]. — 1 specimen, UF 516, Society Islands, Moorea Island, Fringing Reef at NW side of Opu- nohu Bay (- 17.4965, - 149.8625; 17°29’47.4000” S, 149°51’45.0000”W), 0-3 m depth, 13.VII.2006, C. Lydeard, C. McKeon & C. Meyer coll. [24 mm long, 2 mm wide; pigmentation pattern with dorsal wide transverse irregular bands along chaetigers 1-9; pharynx partially exposed; ventral dissection showing a very long muscular tube extending for 2/3 body length]. — 1 specimen, UF 517, Society Islands, Moorea Island, Narrow Reef Flat Around Pt. Faupo (-17.4964, -149.7528; 17°29’47.0400”S, 149°45’10.0800”W), 0-1 m depth, 20.VI.2006, C. McKeon & G. Paulay coll. [42 mm long, 5 mm wide; body with a jaguar-like pigmentation pattern; individual spots with a paler central area, not forming dorsal wide transverse bands; dorsal cirri multiarticulated; acicular lobe double, upper one slightly longer; neurochaetal blades with guard reaching subapical tooth; posterior region with roughly verticillate ovarian tubules; oocytes compressed, each about 80- 100 µm]. — 1 specimen, UF 881, Society Islands, Moorea Island, 1-2 km past CRIOBE station (-17.5145, -149.8548; 17°30’52.2000”S, 149°51’17.2800”W), 0-1 m depth, 30.X.2008, S. Fay & A. Anker coll. [30 mm long, 4 mm wide; body progressively wider posteriorly; pigmentation pattern typical but less widespread than in other specimens; acicular lobe double, invaginated in anterior chaetigers, better exposed in median ones; pharynx invaginated]. — 1 specimen, UF 934, Tuamotu Islands, Makemo Atoll, Mekemo, 31.III.2009, P. Bacchet & J. Letourneaux coll. [43 mm long, 6 mm wide; pigmentation brownish in abundant circular to transversely elliptic dots, grouped into semilunar or triangular, directed posteriorly, larger dots on the dorsal surface at the level of intersegmental areas, middorsal areas corresponding to chaetal lobes pale with a few or none dots; pigmented spots less abundant and smaller progressively towards the posterior region; pigmentation pattern extended along prostomium and lower third of pharynx, especially dorsally, less intense ventrally; pharynx papillae not visible dorsally, hidden under prostomial lobe; eyes brownish, anterior ones twice as large as posterior ones; antennae tapered, 1.5 times longer than the distance between lateral eyes; dorsal and anal cirri pale brownish, ventral cirri pale; dorsal cirri multi-annulated; acicular lobe double, digitate, size variable and sometimes the upper lobe duplicated; neurochaetal blades short, many blades lost, guard reaching subapical tooth]. — 1 specimen, UF 935, Tuamotu Islands, Makemo Atoll, Mekemo, ethanol, 31.III.2009, P. Bacchet & J. Letourneaux coll. [29 mm long, 4.5 mm wide; pigmentation pattern typical; pharynx fully everted; body progressively wider posteriorly; acicular lobe double, better exposed in median chaetigers]. — 1 specimen, UF 936, Tuamotu Islands, Niau Atoll, Niau, 31.XII.2008, P. Bacchet & J. Letourneaux coll. [17 mm long, 2 mm wide; body bent dorsally, with thin transverse, mostly incomplete irregular lines along chaetigers 1-9; pharynx everted, dorsal papilla not seen; antennae longer than interocular distance; acicular lobes double, visible along most chaetigers]. — 1 specimen, UF 1307, Society Islands, Moorea Island, SE corner of Island, near Maatea, just off road (–17.57493, –149.79741; 17°34’29.7480”S, 149°47’50.6760”W), 0-3 m depth, 11.XI.2009, S. McPherson, T. Lotufo & N. Gravier-Bonnet coll. [17 mm long, 2 mm wide; pigmentation pattern with dorsal transverse, thin irregular lines along chaetigers 1-11, most with a median posterior rounded projection; pharynx partially everted, dorsal papilla not seen; acicular lobes double, better exposed along median and posterior chaetigers]. — 1 specimen, UF 1309, Society Islands, Moorea Island, SE corner of Island, near Maatea, just off road (– 17.57493, – 149.79741; 17 °34’ 29.7480” S, 149°47’50.6760”W), 0-3 m, 11.XI.2009, S. McPherson,T. Lotufo & N. Gravier-Bonnet coll. [8 + 11 mm long, 3 mm wide, 15 chaetigers (one removed for sequencing); body broken in two regions, about half-body each; pharynx tube retracted reaching about 2/3 body length, surprising because the posterior region is not hollow but has another muscular cylinder inside; posterior region of pharynx tube with a few long, ventral, transparent muscular fibers attached in a discontinuous series; pigmentation pattern resembling those present in other larger specimens, but antennae shorter, about as long as interocular distance]. — 1 specimen, UF 1364, Society Islands, Moorea Island, Temae at lighthouse (-17.48859, -149.77298; 17°29’18.9240”S, 149°46’22.7280”W), 0.5 - 2.0 m depth, 4.XII.2009, S. McPherson coll. [32 mm long, 4 mm wide; pigmentation, eye size and antennae features as in UF 934; pharynx papillae large, as wide as long; acicular lobe double, digitate, upper lobe slightly longer than lower one; neurochaetal blades short to long, guard reaching subapical tooth]. — 1 specimen, UF 1431, Society Islands, Moorea Island, Atiha Bay, inside barrier reef, on west side of pass (-17.59568, -149.84564; 17°35’44.4480”S, 149°50’44.3040”W), 0.5 - 1.0 m depth, 8.XII.2009, S. McPherson, G. Paulay & C. Meyer coll. [29 mm long, 4.5 mm wide; pigmentation, eye size and antennae features as in UF 934, but dorsal spots resembling a thick ‘T’ with stem directed posteriorly; pharynx papillae pale, rounded, hidden under prostomial lobe; acicular lobe double, digitate, upper lobe slightly longer than lower one; neurochaetal blades short to long, guard reaching subapical tooth]. — 1 specimen, UF 2144, Society Islands, Moorea, mouth of Cook’s Bay (-17.4824, -149.824; 17°28’56.6400”S, 149°49’26.4000”W), lagoonal patch reef, in coral rubble/ Halimeda / green tufting algae, 1-2 m depth, 1.XI.2010, C. Watson coll. [16 mm long, 2 mm wide, 14 chaetigers left; prostomium barely pigmented; anterior eyes twice as large as posterior ones; pigmentation forming a roughly defined wide transverse band on chaetiger 1; body without posterior region]. — 1 specimen, UF 2145, Society Islands, Moorea Island, mouth of Cook’s Bay (-17.4824, -149.824; 17°28’56.6400”S, 149°49’26.4000”W), lagoonal patch reef, in coral rubble/ Halimeda /green tufting algae, 1-2 m depth, 1.XI.2010, C. Watson coll. [15 mm long, 3 mm wide; body laterally bent; prostomium without pigmentation; pharynx not exposed; body pigmentation poorly developed but progressively less intense posteriorly]. — 1 specimen, UF 2146, Society Islands, Moorea Island, mouth of Cook’s Bay, lagoonal patch reef (-17.4824, -149.824; 17°28’56.6400”S, 149°49’26.4000”W), in coral rubble/ Halimeda / green tufting algae, 1-2 m depth, 1.XI.2010, C. Watson coll. [23 mm long, 2.5 mm wide; body laterally curved, slightly distorted, complete, pigmentation pattern typical; pharynx fully exposed; acicular lobe double, better exposed in posterior chaetigers]. — 1 specimen, UF 2229, Society Islands, Moorea Island, near Haapiti (-17.55475, -149.87899; 17°33’17.1000”S, 149°52’44.3640”W), mangroves, deep under rocks and in rubble, 0.5 - 1.0 m depth, 29.XI.2010. A. Anker coll. [37 mm long, 5 mm wide; body with typical pigmentation and extended ventrally to the basal pharynx region, and along chaetigers 14-16; pharynx everted]. — 1 specimen, USNM 19376, Tuamotu Islands, Mekema (Makemo) Island (16°35’S, 143°40’W), RV Albatross, unnumb. Sta., reef flat, ocean side, 20.X.1899 [11 mm long, 1.8 mm wide; a wide dorsal transverse band on chaetiger 1, lateral feebly defined spots on chaetigers 2-5/6; eyes circular, brownish, anterior ones almost twice as large as posterior ones; most cirri on site; pharynx partially everted; most neurochaetal blades lost; anal papilla not visible]. — 1 specimen, ZMUC 2427, Tahiti, RV Galathea 1 Expedition 1845-1847, Sta. 145, 9.XII.1846 [52 mm long, 5 mm wide; macerated, colorless, left parapodium of chaetiger 8 removed for observation (kept in vial); acicular lobe double, blunt, upper tine slightly longer than lower one; neurochaetal blades bidentate, subdistal tooth as wide as distal one; guard approaching subdistal tooth]. — 1 specimen, ZMH-P 1282, no further data [53 mm long, 7 mm wide; prostomium collapsed by pressing body into small container; pigmentation pattern includes abundant brownish, round spots along body, becoming purple laterally, especially in the posterior sector of lateral cushions; middorsally alternating paler and slightly darker areas; antennae blunt, tapered, 7-8 times as long as wide; eyes of similar size, but difficult to observe because of distortion of anterior region; acicular lobe double, digitate, upper and lower tine of about the same length; most neurochaetal blades lost].
Gilbert Islands. 1 specimen, MCZ 463979, Kingsmill Islands, no further data [25 mm long, 3 mm wide; partially dried out, with salt granules adsorbed throughout body; original pigmentation mostly gone and transverse bands now diffuse, a wide one over chaetiger 1 indicates it belongs in H. genetta; antennae blunt, directed laterally, left one broken, right one about as long as interocular distance; dorsal cirri basally articulated; ventral cirri smooth, longer than chaetal lobe; acicular lobe double, upper tine longer, digitate, lower tine wider, triangular, 4/5 as long as upper tine; neurochaetal blades mostly lost, remaining ones with guard reaching subdistal tooth]. — 1 specimen, USNM 26070, Kiribati, Onotoa Atoll, 2.VIII.1951, A. Banner coll. [22 mm long, 3 mm wide; complete; pigmentation retained; first chaetiger with a thick transverse band, anteriorly irregular, posteriorly well-defined; following chaetigers with transverse band progressively thinner and less well-defined, last 7 chaetigers with a series of unconnected dark spots and smaller, paler spots between them; eyes brownish, tiny, anterior ones slightly larger than posterior ones; antennae short, digitate, smaller than interocular distance; acicular lobe double, both tines tapered, upper one slightly longer than lower one].
Cook Islands. 1 specimen, UF 390, Rarotonga Island, W of Ava Avarua, just behind Algal Rim, low tide, under rocks, 0.15 m depth, 20.IX.1984, G. Paulay & G. McCormack coll. [31 mm long, 4 mm wide; complete specimen, reddish brown spots forming irregular transverse bands dorsally; salt masses adhered on chaetal bundles and posterior region; pharynx partially exposed; anterior eyes twice as large as posterior ones; antennae longer than interocular distance; acicular lobes double, variable eroded or damaged, upper tine slightly longer to longer than lower one].
Papua New Guinea. 1 specimen, ZMB 2964, Bismarck Archipelago, Ralum, in coral, 4.IX.1896, F. Dahl coll. [32 mm long, 3.5 mm wide; body bent ventrally, with a faint wide band on chaetiger 1, and scattered dark spots dorsally; left parapodium from chaetiger 8 removed for observation (kept in vial); antennae digitate, as long as interocular distance; eyes barely pigmented, anterior eyes twice as large as posterior ones; acicular lobe double, blunt, subtriangular, upper tine markedly longer than lower one; blades with subapical tooth as large as distal one, guard approaching subdistal tooth]. — 2 specimens, ZMHU 1285, Bismarck Archipelago, New Britain island (05°44’S, 150°44’E), von Gutze coll., no further data [45- 50 mm long, 6-7 mm wide; macerated, smaller one colorless, the other with abundant dorsal round brownish spots along body, without transverse bands; acicular lobe double, digitate, tines of similar size or upper one slightly larger].
Solomon Islands. 4 specimens, BMNH 1970.318, Royal Society Expedition to the Solomon Islands, 1965, Graham Point, under boulders in silty sand, 21.IX.1965, MTL & LWM coll. [17-30 mm long, 2-3 mm wide; most cirri and neurochaetal blades on site, cirri without tips; pigmentation pattern variable, all with a wide transverse band in chaetiger 1, remaining body with either abundant round small brownish spots, or combined with three larger half-moon shaped spots per segment positioned over between chaetal lobes region; antennae long, 5-6 times as long as wide; eyes brownish, anterior ones slightly larger than posterior ones; acicular lobe double, neurochaetae broken, remaining blades bidentate, subdistal tooth as wide as distal one, guard approaching subdistal tooth; pharynx partially exposed in 3 specimens, dorsal papilla slightly as long as wide]. — 1 specimen, BMNH 1970.320g, Royal Society Expedition to the Solomon Islands, 1965, Graham Point, below boulders in shell gravel, 5.X.1965, LWM coll. [38 mm long, 5 mm wide; most cirri and neurochaetal blades on site; a wide transverse band in chaetiger 1, following chaetigers with abundant round small brownish spots, somehow fused into larger spots, better defined along anterior chaetigers; antennae long, 5-6 times as long as wide; eyes brownish, anterior ones slightly larger than posterior ones; acicular lobe double; pharynx partially exposed, basal ring with brownish, irregulary longitudinal lines, dorsal papilla colorless, twice as wide as long].
Indonesia. 1 specimen. RMNH 1281, Maluku, RV Siboga Exped. Stat. 181 (Ambon, anchorage), 36-54 m depth, dredge and trawl, reef-exploration, muddy bottom, sand + coral, 5-11.IX.1899 [32 mm long, 3 mm wide; most cirri and neurochaetal blades lost; pigmentation pattern with a wide transverse band in chaetiger 1, remaining body with abundant round brownish spots; antennae long, 7-8 times as long as wide; eyes colorless].
Timor. 1 specimen. RMNH 427, East Timor, between Timor and Nusa Besi, anchorage, RV Siboga Exped. Stat. 282 (08°25.2’S, 127°18.4’E), 27-54 m depth, trawl, dredge, reef expl., sand, coral, 15-17.I.1900 [28 mm long, 3.5 mm wide; body complete, partially dried-out, bent backwards a thick transverse, dorsal, dark brown band in chaetiger 1; parapodia not removed to avoid further damage].
Australia. 1 specimen, AM 2619, Low Isles, off Port Douglas, Queensland, no further data [31 mm long, 5 mm wide, 16 chaetigers; complete, many pale-brownish, irregularly rounded spots along dorsal surface, no transverse bands; pharynx partially exposed, dorsal papilla conical, twice as wide as long; antenna digitate, blunt, 4-5 times as long as wide; eyes colorless, anterior ones slightly larger than posterior ones; several parapodia previously removed; left parapodia of chaetigers 2 and 8 removed for observation (kept in vial); chaetigers with about 20 neurochaetae; anterior chaetigers with longer blades, all bidentate, subdistal tooth slightly smaller or as wide as distal one; guards mostly broken, approaching subdistal tooth]. — 2 specimens, BMNH 1931.7.1.23/24, Great Barrier Reef Expedition, Low Isles, no further data [one macerated, the other perfect; both with abundant dark dorsal spots, with a pale wide band in chaetiger 2, better defined in best-preserved specimen; body 51-53 mm long, 3.5-5.0 mm wide; right parapodia of chaetigers 8 and 9 already removed; most dorsal cirri lost, some as long as body width (excluding parapodia); acicular lobes double, upper tine slightly wider and twice longer than lower one].
DISTRIBUTION. — Western Pacific from Japan to Australia, including the Marshall Islands, and the French Polynesia, in 0-54 m depth, in coralline rocks to mixed bottoms, including silty sands.
DIAGNOSIS. — Hesione with prostomium rectangular; parapodia with dorsal cirri basally cylindrical, dorsal cirrophore as long as wide; larger acicula blackish; acicular lobe double, tines digitate, subequal; neurochaetal blades bidentate, 3-5 times as long as wide; subdistal tooth as large as distal one, with guards approaching subdistal tooth.
DESCRIPTION
Specimen UF 81, complete, subcylindrical, laterally bent, tapered posteriorly. Body with brownish rounded spots, variably fused middorsally forming irregular transverse bands along chaetigers 1-11, barely defined in chaetiger 2 (Fig. 15A), extended into lateral cushions, progressively less defined, posterior segments with a spotty pattern in ethanol. Tentacular cirri, dorsal cirri and neuropodial lobes whitish. Body 31 mm long, 3.5 mm wide; right parapodia of chaetigers 13 and 14 removed for molecular studies.
Prostomium slightly as wide as long (Fig. 15B), anterior margin rounded, projected anteriorly, without depression nor pigmentation, lateral margins straight, posterior margin partially covered by tentacular segment projection, longitudinal depression shallow, barely pigmented. Antennae tapered, digitate, 5-6 times as long as wide, longer than interocular distance. Eyes dark brown, circular; anterior eyes slightly larger than posterior ones.
Tentacular cirri twisted, some without tips, longest ones reaching chaetiger 5. Lateral cushions projected, most separated into a larger, anterior region, and a smaller posterior one, surface smooth.
Parapodia (Fig. 15C) with chaetal lobes wider than high, truncate; dorsal cirri with cirrophores about twice as long as wide, cirrostyle variably contracted, twisted, cylindrical, smooth basally, annulated medially, articulated distally, as long as body width (without parapodia). Ventral cirri smooth, variably damaged, if complete surpassing tip of chaetal lobe.
Neuraciculae blalckish, larger one markedly thicker than smaller one. Acicular lobe double, tines digitate, of similar size, or upper one slightly longer (Fig. 15C [inset]).
Neurochaetae about 25 per bundle, blades at a certain angle from handles, decreasing in size ventrally, 3-5 times as long as wide, each blade bidentate, subdistal tooth wider than distal one, guards, if complete, approaching subdistal tooth (Fig. 15D).
Posterior region tapered into a blunt cone (Fig. 15E); pygidium conical, anus with 8 rounded, low papillae.
Pharynx partially exposed, two smooth rings of similar length. Gonads visible through body wall in posterior region. Oocytes about 100 µm.
Pigmentation
There is a remarkable variation of dorsal pigmentation intensity in this species about a similar pattern with a whitish, yellowish or pinkish background. There is a transverse band on chaetiger 1, no transverse band in chaetiger 2, and along chaetigers 3-16 transverse bands become progressively shorter and less defined (Fig. 16 A-D), from having a straight anterior margin, with a posterior margin variably expanded caudally, to a series subcontinuous bands made up with irregular spots, sometimes as three as long as wide bands per segment, or no such distinct separation, especially in medial and posterior chaetigers (Fig. 16 E-H). Lateral cushions usually pigmented; spots variably fused into larger spots or separated from each other. Tentacular cirri, dorsal cirri, and neuropodial lobes paler than dorsal background or of the same pigmentation.
REMARKS
Hesione genetta Grube, 1867, restricted, is among the most colorful species in the genus, and similar specimens from the Indian Western Pacific Ocean have been regarded as conspecific. Because of the differences are consistent, the species is being restricted and other, similarly pigmented specimens are described as new species below.
Grube (1867: 64) indicated that the collector of H. genetta was Mr Godeffroy from Hamburg, that it was collected from Samoa (Grube 1867: 65) and that more than a single specimen was available (Grube 1867: 65). This would imply that the specimens deposited in Hamburg might be syntypes, and they were regarded as such with hesitation, because there are no more details in the labels regarding collector, or collecting dates. If this is combined with the fact that the specific locality in one of the labels was not included in the description, their status as types is doubtful. This explains why another specimen from the same area as the type was used for the redescription: this pecimen matches the body length indicated in the description. Overall, and as far as the presumptive syntypes condition allows the comparison, the specimen UF 81 matches both the original description and the morphological features, but because it was collected recently, it allowed to illustrate the remaining pigmentation pattern.
Grube (1867) did not explain the etymology for Hesione genetta; however, genets are small wild cats, and the southern European species (Genetta genetta (Linnaeus, 1758)) has its body with dark spots, more or less arranged into longitudinal lines, and a tail with a series of dark bands throughout its length. In H. genetta there are irregular spots along dorsal surfaces, and they can fuse into irregular transverse bands; as indicated above, these bands are missing or usually poorly defined on chaetiger 2, and better defined on most other chaetigers, and their anterior margins are sometimes straight resulting from a more complete merging of adjacent spots, whereas the posterior margin is irregular. Grube (1867: 65) indicated: “Auf dem rosigen oder blassvioleten Grunde des mit dem Rüssel 30 mm langen Thieres erscheinen an jedem Segment etwa 5 bis 6 Querreihen kleiner dunkler Rückenfleckchen, von denen die mittleren Reihen fast zu einer Querbinde verfliessen” (Transl.: The rosy or pale violet background, including the pharynx is 30 mm long, with about 5 to 6 transverse rows of small dark dorsal little spots, of which the middle rows almost merge into a transverse band, at each segment). Grube later (1878: 104) indicated: “Semiteres, elongata utrinque sensim attenuata, ex cinereo margaritacea splendens cute laevi densiore, supra violaceo fusco maculate. Segmenta 19 latitudinae 10mum versus crescentia, a 12di decrescentia, plerumque alterum tantum latiora quam longa, anteriora et posteriora breviora, omnia seriebusmacularum transversis fere 6 ornata, maculis ipsis transverse ovalibus, media cujusque segmenti majore.” (Transl.: Subcylindrical, gradually tapered sides, far from bright gray pearly colored, smooth skin thicker, over violet dark spots. 19 segments, progressively thicker to segment 10, decreasing from segment 12, each usually only one time as wide as long, anterior and posterior ends thinner, all with about 6 transverse series of spots adorned with intertwined oval spots, over the middle of each segment). These pigmentation patterns are common but, as shown above, the definition of transverse bands is variable and in some specimens they are not distinct, but they are conspecific as indicated by COIbarcoding (Fig. 16D, G). Horst (1924: 193) indicated that acicular lobes were subequal, and most specimens conform to this feature.
Two other species, traditionally regarded also as H. genetta, have better defined transverse bands, along both anterior and posterior margins, with the first one usually wider (or longer) than following ones, but the first band is over chaetiger 2, with chaetigers 1 and 3 often without transverse bands. Irregular spots may be present and this similarity explains why they were regarded as variations of the same pigmentation pattern, but this apparently subtle difference is consistent, and long-lasting, and herein these two variants, one from the Western Indian, and the other from the Western Pacific, are regarded as distinct species and described as H. mooreae n. sp. and H. paulayi n. sp. respectively (see below).
Consequently, those records for a species having well-defined transverse bands, especially on chaetiger 2, do not belong in H. genetta but in H. mooreae n. sp., such as Willey (1905: 267) for Sri Lanka, and Fauvel (1953b: 105) for India; whereas those that might match H. paulayi n. sp. would be the records by Fauvel (1919b: 370; 1923b: 15-16; 1947b: 89-90) for the Gambier Islands, and Horst (1924: 193) for Indonesia. Hartman (1954: 622) recorded H. genetta for the Marshall Islands and indicated its distribution as ranging from Sri Lanka to Samoa, including the Philippine islands. However, she probably included some other species under the same name, as indicated above; one is newly described below as H. paulayi n. sp.; the record by Fauvel (1953b: 105) for India probably belongs in H. mooreae n. sp.
description: Published as part of Salazar-Vallejo, Sergio I., 2018, Revision of Hesione Savigny in Lamarck, 1818 (Annelida, Errantia, Hesionidae), pp. 227-325 in Zoosystema 40 (12) on pages 251-257, DOI: 10.5252/zoosystema2018v40a12, http://zenodo.org/record/3741548