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Comprehensive Description

provided by Smithsonian Contributions to Zoology
Malmgreniella maccraryae

Harmothoe lunulata.—Taylor, 1971:70 [not Delle Chiaje, 1830].

? Malmgrenia lunulata. variety Gardiner, 1976:90, fig. 3a–e [part; not USNM 52850 = Lepidonopsis humilis (Augener)].

Malmgreniella sp. B.—Weston, 1984:21–20, figs. 21–15, 16a–g.

Malmgrenia lunulata.—Fox and Ruppert, 1985:127, 194, 254 [not Delle Chiaje, 1830].

MATERIAL EXAMINED.—NORTHWESTERN ATLANTIC OCEAN: North Carolina: Banks Channel, Wrightsville Sound, 1967, taken from brittle star, A.B. McCrary, collector, paratype (USNM 55065). Wrightsville Beach, intertidal, commensal on brittle star Amphipholis gracillima (Stimpson), Apr 1972, Mar 1973, S.L. Gardiner and T. Fox, collectors, holotype (USNM 52050) and 2 paratypes (USNM 52849, 55066, as ?Malmgrenia lunulata, variety by Gardiner, 1976). Georgia: Off Georgia, 31°55′N, 80°51′W, 8 m, Texas Instruments, R/V Pierce sta 4A, 20 Feb 1977, 3 specimens (USNM 59169). Florida: Off Florida, 29°27′N, 81°03′W, 20 m, R/V Pierce, sta 7A, 4 Mar 1977, 3 specimens (USNM 59171). Off Virginia Key: near Miami, 1 m, on brittle star Amphioplus sepultus Hendler, 23 Feb 1970, G. Hendler, collector, 2 paratypes (USNM 55067); 26 Feb 1970, 2 specimens (USNM 133560; LACM).

GULF OF MEXICO: Florida: Tampa Bay, J.L. Taylor, collector, 7 paratypes (USNM 45513, as Harmothoe lunulata by Taylor, 1971). Hillsborough Bay, Tampa, sand and shell, 7 May 1975, S.L. Santos, collector, 9 paratypes (USNM 55068). Mississippi-Alabama-Florida (MAFLA) sta IV-2419, off Apalachicola River, Feb 1978, 29°47′N, 84°05′W, 10 m, medium-fine sand, 2 specimens (USNM 89685). Alabama: Mouth of Mobil Bay, 30°14′N, 88°03′W, 6.4 m, Mobile Oil sta Mc 151A,D, Jul 1978, 40 specimens (USNM 70075–6). About 3 miles SE of Dauphin Island, 30°11′N, 88°07′W, 13 m, Continental Shelf Assoc. sta 14, 18 Sep 1981, 6 specimens (USNM 71156). Texas: Bay City-Freeport, inner shelf, 28°53′N, 95°15′W, 15 m, T.R. Calnan, collector, 2 specimens (USNM 68008), as Malmgreniella sp. B. by Weston, 1984: Southwest Florida (SOFLA) sta 25B, Nov 1980, 24°47′N, 82°13′W, 24 m, silt-clay, 2 specimens (USNM 89684). South Texas Outer Continental Shelf (STOCS) sta II-1, off Port Aransas, Fall 1976, 27°40′N, 96°59′W, 22 m, sandy silty clay, 1 specimen (USNM 89688); sta IV-4, off Port Isabel, Fall 1976, 1977, 26°10′N, 97°08′W, 15 m, sand, 2 specimens (USNM 89686–7).

DESCRIPTION.—Holotype 7 mm long, 2.5 mm wide including setae, with 33 segments and 15 pairs of elytra. Paratype from Wrightsville Sound (USNM 55065, male with sperm) 5 mm long, 2.5 mm wide, with 31 segments and 14 pairs of elytra. Paratypes from Tampa Bay (USNM 45513) 4–6 mm long, 2–3 mm wide, with 27–34 segments and 13–15 pairs of elytra. Body short, depressed, tapering slightly anteriorly and posteriorly. Dorsum with transverse dark bands on posterior third of body; ventrum with wide longitudinal stripe along body or confined to posterior segments. Elytra up to 15 pairs, some sexually mature males with fewer than 15 pairs and fewer segments. Elytra oval, without tubercles, with scattered micropapillae along lateral and posterior borders and few on surface, with dark pigment spots on area of attachment to elytophores, on larger medial semilunar areas, and sometimes additional scattered spots (Figure 25B,C; Gardiner, 1976, fig. 3a,e; Weston, 1984, fig. 21–16a).

Bilobed prostomium with anterior lobes rounded to subtriangular, without distinct cephalic peaks; anterior pair of eyes larger than posterior pair, located just anterior to widest part of prostomium, median antenna with ceratophore in anterior notch, with rather short, subulate style; ceratophores of lateral antennae inserted ventrally, meeting midventrally, with styles about half as long as median antenna; palps long, smooth, tapered; tentaculophores each with 1–2 setae on inner side and pair of dorsal and ventral tentacular cirri, longer than median antenna and shorter than palps; antennae and tentacular cirri minutely papillated; light, net-like pigmentation on prostomium, tentaculophores, bases of styles of median antenna, and tentacular cirri (Figure 25A; Weston, 1984, fig. 21–16b). Segment 2 with biramous parapodia and long ventral buccal cirri similar to tentacular cirri. Pharynx with 9 pairs of border papillae and 2 pairs of hooked jaws.

Notopodium short, rounded, with projecting acicular lobe on lower side; neuropodium with subconical presetal acicular lobe, thick, digitiform supraacicular process, and shorter, rounded postsetal lobe (Figure 25D,E; Gardiner, 1976, fig. 3d). Notosetae numerous, forming radiating bundle, slightly stouter than neurosetae, short to long, with close-set spines along curved borders and tapered blunt tips (Figure 25F; Weston 1984, fig. 21–16d). Neurosetae moderate in number, forming fan-shape bundle; supraacicular neurosetae with longer spinose regions and secondary tooth rather far removed from slightly hooked tips (Figure 25G; Weston, 1984, fig. 21–16e,f); subacicular neurosetae with shorter spinose regions and bare, slightly hooked tips (Figure 25H; Weston, 1984, fig. 21–16g); neurosetae of segment 2 more slender than following, upper ones with bifid tips, middle and lower ones with slender, slightly clubbed, entire tips. Cirrophores of dorsal cirri cylindrical, wider basally, with papillate styles extending beyond tips of neurosetae; dorsal tubercles nodular; ventral cirri short, subulate, papillate, extending to tip of neuropodial postsetal lobe (Figure 25E). Pygidium medial to posterior, small parapodia, with pair of long anal cirri.

BIOLOGY.—Malmgreniella maccraryae was collected intertidally in Wrightsville Sound from a ophiuroid by A.B. McCrary and from the burrowing ophiuroid Amphipholis gracillima (Stimpson) by S.L. Gardiner and T. Fox. From Virginia Key near Miami, the species was collected subtidally on Amphioplus sepultus Hendler by G. Hendler.

ETYMOLOGY.—The species is named for Anne B. McCrary, who first collected one of the paratypes and who first noted its association with a brittle star.

DISTRIBUTION.—Northwestern Atlantic Ocean from North Carolina to southern Florida and Gulf of Mexico. Intertidal to 34 meters (see Weston, 1984).
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bibliographic citation
Pettibone, Marian H. 1993. "Scaled polychaetes (Polynoidae) associated with ophiuroids and other invertebrates and review of species referred to Malmgrenia McIntosh and replaced by Malmgreniella Hartman, with descriptions of new taxa." Smithsonian Contributions to Zoology. 1-92. https://doi.org/10.5479/si.00810282.538