Trophoniella jareckiorum, SALAzAR-Vallejo, 2012

SALAzAR-Vallejo, Sergio I., 2012, Revision of Trophoniella Hartman, 1959 (Polychaeta, Flabelligeridae), Zoosystema 34 (3), pp. 453-519 : 453-519

Trophoniella jareckiorum n. sp.

( Fig. 19 )

TYPE MATERIAL. — Western Atlantic Ocean , Caribbean Sea. Holotype ( LACM-AHF 2494 ), British Virgin Islands, Guana Island, White Bay, c. 15 m off shore, shoreward of first two finger reefs (18°28’27”N, 64°34’34”W), artificial reef matrix structures, 1.5 m, 9.VII.2000,

T. Zimmerman, G. Hendler, R. Ware, K. Fitzhugh. — 2 paratypes ( LACM-AHF 2495 ), a complete specimen and an anterior fragment, damaged, body and tunic irregularly broken, British Virgin Islands, Guana Island , N bay lagoon, rocky intertidal, just W of wooden dock (18.482°N, 64.575°W), algal covered coral rubble, snorkel, hand, 25.VII.1999, Don Cadien (complete 20 mm long, 2 mm wide, cephalic cage 3 mm long, 49 chaetigers; gonopodial lobes not seen) .

ADDITIONAL MATERIAL. — Western Atlantic Ocean , Caribbean Sea. Anterior fragment ( LACM-AHF 2496 ), British Virgin Islands, Guana Island, N bay lagoon, W end, directly offshore from house and wooden dock (18°26’54”N, 64°34’29”W), algae off coral rubble, snorkel, scraper, 0.5 m, 3.VII.2000, K. Fitzhugh (6 mm long, 1.5 mm wide, cehalic cage 1.5 mm long, 27 chaetigers; tunic transparent, branchial plate entire).— 3 specimens ( LACM-AHF 2497 ), juveniles, British Virgin Islands, Guana Island, Long Point, c. 70 m SE of small dock, in a protected area at bottom of furrow (18.486°N, 64.583°W), 12-15 ft, SCUBA, hand, 5.VII.2000, T. Zimmerman & G. Hendler (3-12 mm long, 1-2 mm wide, cephalic cage 1-2 mm long, 24-40 chaetigers; smallest juvenile with first neurohooks in chaetiger 4) .

TYPE LOCALITY. — Guana Island, British Virgin Islands.

DISTRIBUTION. — British Virgin Islands, in shallow water (1-2 m) mixed bottoms.

ETYMOLOGY. — The specific name is derived after Drs Henry Jarecki and Lianna Jarecki. The former is the head of the family which owns Guana Island, and who recognised the value of a protected nature preserve on this beautiful island, and the latter established the Guana Marine Science Program under which these specimens were collected (see Martin 2002 for other details about the expedition).

DESCRIPTION

Holotype whitish, without posterior region ( Fig. 19A ).Tunic papillated, rugose, partially eroded into an areolated surface, without sediment particles. Body cylindrical, slightly tapering posteriorly, posterior section slightly swollen by contraction, 14 mm long, 3 mm wide, cephalic cage 4 mm long, 51 chaetigers.Body papillae cirriform, distally expanded, arranged in three irregularly alternating transverse rows (better seen in non-contracted specimens), and in longitudinal rows as two dorsally and four ventrally ( Fig.19D ), ventral papillae smaller.

Anterior end exposed ( Fig. 19B, C ). Cephalic hood short, smooth,margin smooth.Prostomium low,pale. Eyes dark-brown. Caruncle pale, well developed, extended along ⅔of the branchial plate,median keel and lateral ridges elevated.Palps pale, thick, twice as long as branchial plate, palp keels pale, rounded. Lips well developed, distorted by pharynx eversion.Branchiae pale, cirriform, sessile on a distally cleft, tongue-like protuberance(entire in juveniles,LACM-AHF 2496), arranged in two lateral groups, in 3-4 longitudinal rows per group, with about 60 filaments per group; filaments longer basally, longest about as long as 1⁄₃ palp length. Nephridial lobes not seen.

Cephalic cage chaetae barely longer than body width. Chaetigers 1-2 involved in the cephalic cage; chaetae arranged in short, dorso-lateral or lateral series, 5-6 notochaetae and 4-5 neurochaetae per bundle. Anterior dorsal margin of first chaetiger with a small trilobed projection. Anterior chaetigers with papillae markedly longer than those present in following chaetigers. Chaetigers 1-3 slightly progressively longer. Chaetal transition from cephalic cage to body chaetae abrupt; first anchylosed neurohooks present in chaetiger 5. Ventral gonopodial lobes transverse, oblong, eroded in chaetiger 5.

Parapodia poorly developed, chaetae emerge from the body wall ( Fig. 19D ). Parapodia lateral, median neuropodia ventrolateral.Notopodia with a basal and a lateral papillae, longest papillae about 1⁄₃ as long as notochaeta. Neuropodia with smaller papillae.

Median notochaetae arranged in short, transverse series, 4-5 notochaetae per bundle, about as long as 1⁄₄-1⁄₅ body width; all notochaetae multiarticulated, each with small articles in a short basal portion, then medium-sized and longer articles medially and distally ( Fig. 19F ). Neurochaetae multiarticulated capillaries in chaetigers 1-4, falcate anchylosed neurohooks from chaetiger 5,arranged in transverse series,five per bundle in most chaetigers ( Fig. 19G ), only four in posterior chaetigers,each subdistally slightly expanded;depressed, short rings only in the basal region, blade pale, flat, wider than handle, with tips slightly incurved, entire.

Posterior end not known.

REMARKS

Trophoniella jareckiorum n. sp. is closely allied to T. salazarae n. sp. from the tropical Pacific Mexican coast, because both have an opaque tunic which does not include sediment grains. They differ especially on the general pigmentation pattern and in the number and type of notochaetae; thus, T. jareckiorum n. sp. is whitish, whereas T. salazarae n. sp. is grayish to reddish, finely speckled with tiny black spots, has fewer notochaetae (4 - 5 vs 5-8 per bundle), and has long articles medially and distally,whereas the long articles are restricted to the distal portion in T.salazarae n. sp.

Figures

FIG. 19. — Trophoniella jareckiorum n. sp.: A, holotype (LACM-AHF 2494), lateral view; B, same, anterior end, dorsal view; C, same, anterior end, ventral view, pharynx exposed; D, paratype (LACM-AHF 2495), median fragment, slightly stained with methyl green; E, holotype, notopodium from chaetiger 12; F, same, notochaetal basal and medial regions; G, same,neuropodium from chaetiger 12 (insert: close-up of largest neurohook tip). Scale bars: A, 2.3 mm; B, 0.6 mm; C, 0.7 mm; D, 0.4 mm; E, 110 µm; F, 30 µm; G, 112 µm.