Armandia garretti Magalhães & Rizzo & Bailey-Brock 2019, sp. nov.
Creators: name: Magalhães, Wagner F.
name: Rizzo, Alexandra E.
name: Bailey-Brock, Julie H.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Opheliida
Opheliidae
Armandia
Armandia garretti

description: Armandia garretti sp. nov.
Figures 1 (A–C), 2 (A–D), 3 (A–C) and 4 (A–E)
Material examined. Holotype: Hawaii: Pearl Harbor, Waiau discharge: 21°23'15.63" N, 157°57'38.39" W, shallow subtidal, July/13/1999, coll. R. Brock (BPBM-R3881); Paratypes: same place, date and collector as holotype (8 spms, BPBM-R3882). Additional material: Pearl Harbor, Waiau discharge: 21°23'15.63" N, 157°57'38.39" W, shallow subtidal, July/13/1999, coll. R. Brock (2 spms on SEM stub); Pearl Harbor, Oahu, #2, discharge at Waiau Generating Station, 21°23'15.63" N, 157°57'38.39" W, shallow subtidal, June /2013, coll. R. Brock (82 spms). Maunalua Bay, Oahu, among branches of the invasive green alga Avrainvillea amadelpha, intertidal depths, 21°16'49.4" N, 157°43'48.5" W, coll. W. Magalhães and B. Dugan, Mar /2010: Sta. A 4R3 (5), Sta. A 4R2 (3); Sta. A 1R1 (3); Sta. A 1R4 (2); Sta. S 2R2 (3); Sta. S 1R3 (3); Sta. S 3R1 (7); Sta. A 10R1 (5); Sta. A 7R1 (1); Sta. S 1R2 (2); Sta. A 4R3 (5); Sta. A 2R3 (1). Kaneohe Bay: Coconut Island beach, Aug /1983, coll. J. Bailey-Brock (2); Kokokahi, fringing reef north of Likeke place, 0-2 m, May/23/2017, coll. IZ team and G. Paulay (1, UF 005392). EMAP Hawaii 2006, Sta. 65, Kahoiawa Bay, Big Island, 19°48'13.20" N, 156°00'53.04" W, Aug /2006, 9 m, coral/sandy bottom (many); Sta. 19, Keawanui Bay, Big Island, 20°06'48.30" N, 155°53'07.74" W, Aug /2006, 9 m, coral/sandy bottom (5); Sta. 39, Kawaihae Bay, Big Island, 19°59'14.16" N, 155°50'12.06" W, Jul /2006, 20 m, coral/sandy bottom (10); Sta. 30, Kaneohe Bay, Oahu, 21°28'29.64" N, 157°48'09.36" W, Jul /2006, 2 m, coral/sandy bottom (2); Sta. 57, Hapuna Bay, Big Island, 19°59'38.70" N, 155°49'43.26" W, Jul /2006, 8 m, coral rubble (1); Sta. 54, Kaneohe Bay, Oahu, 21°25'00.18" N, 157°47'04.80" W, Sep /2006, 6 m, mud (8). NCCA Hawaii 2010, Sta. 0 7, Kaneohe Bay, Oahu, 21°27'02.04" N, 157°48'48.06" W, 1 m (3).
Diagnosis. Parapodia biramous, symmetrical, with parapodial prechaetal lobe, ventral lobe, and dorsal cirrus. Anal tube funnel-shaped, slightly longer than wide with 12–14 transversal striations; up to four pairs of marginal papillae of similar length, digitiform; one internal, unpaired ventral anal cirrus, crenulated and short; one pair of digitate basal papillae.
Description. Holotype 8.2 mm long, 0.4 mm wide for 28 chaetigers. Paratypes 5.5–7 mm long, 0.4 mm wide for 27–28 chaetigers. Body slender, slightly tapering towards anterior and posterior ends (Fig. 4A). Prostomium conical, excluding palpode, longer than wide; palpode as long as 1/3 prostomial length, clavate (Figs 1A; 2A; 4B). A pair of black eyes deeply and ventrally embedded in prostomium and third eyespot on dorsal side, also embedded in prostomium (Figs 1A; 2A). A pair of ring-shaped nuchal organs present (Figs 2A; 4B); pharynx conical and lacking oral tentacles (Fig. 1A). Branchiae present from chaetigers 2–26 on holotype and absent on last 2–3 chaetigers on paratypes; branchiae long, approaching dorsal midline but not meeting dorsally (Figs 2A; 4A, B); last 2–3 branchiae shorter and last pair of branchiae significantly shorter than preceding one; branchiae without pigmentation.
Parapodia biramous, symmetrical, with parapodial prechaetal lobe, ventral lobe, and dorsal cirrus (Figs 2D; 4C); chaetiger 1 with quadrangular parapodial prechaetal lobe and minute ventral lobe; from chaetiger 2 to posterior end, prechaetal lobe become more conical and ventral lobe rounded and more distinct from parapodial bundle; dorsal cirrus minute, from chaetiger 2 and absent on last chaetigers. Simple capillary chaetae in two bundles; notochaetae about three times longer than neurochaetae; 6–8 anteriorly and reducing to 4–6 posteriorly; notochaetae slightly longer than branchiae when branchiae is best developed (Fig. 4C) and longer than branchiae posteriorly. Neurochaetae six capillaries anteriorly and 4–6 posteriorly. Noto- and neuropodial capillaries of last five chaetigers of same length and longer than preceding chaetigers. Lateral eyespots anterior to parapodia 7 on 11 chaetigers (chaetigers 7–17), black, usually rounded; eyespots of chaetiger 7 and 17 of about a third the size of others, also rounded.
Anal tube funnel-shaped, slightly longer than wide, as long as last 2–3 chaetigers and with 12–14 transversal striations (Figs 1B, C; 2B, C; 4D, E). Posterior border provided with up to four pairs of marginal papillae of similar length, digitiform, about ¼ in length of anal tube (Figs 1B, C; 2B, C; 4D, E); an internal, unpaired ventral anal cirrus present, thick at base and attached ventrally where ventral incision starts, forming triangular shaped mark (Fig. 2C); unpaired ventral cirrus crenulated and short, projecting outwardly (Figs 2B, C; 3C; 4D, E). A pair of basal papillae present, longer and thicker than marginal papillae, digitate (Figs 1B, C; 2B, C; 3C; 4D, E).
Description of juveniles. Individuals with juvenile characteristics had 15–25 chaetigers. Juveniles with up to 20 chaetigers lacked prostomial palpode, branchiae and had the pygidium with distinct and bulbous pair of basal cirri and still developing anal tube (Fig. 3A). Prostomial palpode observed in individuals with 24–25 chaetigers (Fig. 3B). One individual with 24 chaetigers had branchiae from chaetigers 3 to 11; branchiae short and digitate. Another juvenile with 25 chaetigers had branchiae from chaetiger 2 and lacked only on last six chaetigers. Anal cone start developing with a short tube bearing a pair of basal cirri with several minute papillae (Fig. 3C). Prostomial palpode and unpaired crenulate anal cirrus present in juveniles with 25 chaetigers. Prostomial palpode originates from a slit on the dorsal part of the prostomium and individuals with 20 chaetigers already had developed slit but lacked palpode (Fig. 3B). Development of prostomial palpode, branchiae and anal cone seem to be simultaneous.
Remarks. Armandia garretti sp. nov. is most similar to Armandia maculata from Bermuda, Armandia intermedia from Senegal and Armandia paraintermedia from Lizard Island in regards to the shape of the anal cone with a deep ventral incision and shape of the anal papillae. Uebelacker (1984) described specimens of A. maculata from the Gulf of Mexico having marginal anal papillae digitiform to filiform ranging from none to 14 pairs, basal anal papillae were not described and the unpaired anal cirrus long and crenulate. Armandia garretti sp. nov. had always four pairs of digitiform marginal anal papillae, one pair of distinct basal anal papillae, elongate and thicker than marginal papillae and a short and crenulate unpaired anal cirrus. Armandia paraintermedia and A. garretti sp. nov. differ from A. intermedia on the number of segmental eyes (11 pairs in both A. garretti sp. nov. and A. paraintermedia and 13 pairs in A. intermedia) and absence of a parapodial dorsal cirrus in A. intermedia. Armandia garretti sp. nov. differs from A. paraintermedia in relation to the size of the segmental eyes (smaller pairs in chaetigers 7 and 17 in A. garretti sp. nov. and chaetigers 16 and 17 in A. paraintermedia), number of marginal anal papillae (3 pairs in A. parantermedia and 4 pairs in A. garretti sp. nov.), shape of prechaetal lobe (conical in A. garretti sp. nov. and asymmetrical in A. paraintermedia), and shape and length of the unpaired anal cirrus being short and crenulate in A. garretti sp. nov. and long and smooth in A. paraintermedia.
Etymology. This species is named after Garrett Lynch, a marine biologist, stomatopod enthusiast, lab mate and friend of the authors (W.F.M. and J.H.B-B.), who has helped collecting many polychaetes on the south shore of Oahu, including samples of this new species from Maunalua Bay.
Distribution. The type locality is Pearl Harbor (Oahu). This species has been collected at several localities on Oahu (Pearl Harbor, Maunalua Bay, Kaneohe Bay) and Big Island (Keawanui, Kawaihae, Hapuna, and Kahoiawa bays) from intertidal to 20 m in mud, sand, and coral rubble.
Armandia garretti sp. nov. is abundant throughout several stations sampled in Pearl Harbor, Hawaii (J.H.B-B. and R. Brock personal observation). Juvenile individuals were caught on the 0.25 mm sieve in February, July, November and December indicating that this species probably reproduces throughout the year.
description: Published as part of Magalhães, Wagner F., Rizzo, Alexandra E. & Bailey-Brock, Julie H., 2019, Opheliidae (Annelida: Polychaeta) from the western Pacific islands, including five new species, pp. 209-235 in Zootaxa 4555 (2) on pages 211-215, DOI: 10.11646/zootaxa.4555.2.3, http://zenodo.org/record/2624293