Harmothoe Kinberg, 1856

Barnich, Ruth & Fiege, Dieter, 2009, Revision of the genus Harmothoe Kinberg, 1856 (Polychaeta: Polynoidae) in the Northeast Atlantic, Zootaxa 2104 (1), pp. 1-76 : 6-7

Harmothoe Kinberg, 1856

Type species. Harmothoe spinosa Kinberg, 1856 (revised by Barnich et al. 2006).

Andresia Prenant, 1924: 19 [ A. ampullifera => H. areolata ( Grube, 1860) ].

Evarne Malmgren, 1866: 71 [ E. impar (not Polynoe impar Johnston, 1839 ) => H. fragilis Moore, 1910 ].

Evarnella Chamberlin, 1919: 39 , 40 [new name for Evarne , pre-occupied in Mollusca].

Lagisca Malmgren, 1866: 65 [ L. rarispina => H. rarispina (M. Sars 1861) ].

Laenilla Malmgren, 1866: 73 [part: only lectotype of L. glabra => H. glabra ( Malmgren, 1866) , second syntype => Malmgreniella andreapolis ( McIntosh, 1874a) cf. Pettibone 1993a].

Paranychia Czerniavsky, 1882: 179 [ P. taurica => indeterminable Harmothoe ].

Tricosmochaeta Morgera, 1918: 1 [ T. trilobocephala => H.? impar ( Johnston, 1839) ].

Diagnosis. Body dorsoventrally flattened, short, with up to about 50 segments; dorsum more or less covered by elytra or short tail region uncovered. Fifteen pairs of elytra on segments 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 26, 29, 32. Prostomium with distinct cephalic peaks and three antennae; lateral antennae inserted ventrally to median antenna. Position of anterior pair of eyes variable, posterior pair situated dorsally near hind margin. Parapodia with elongate acicular lobes with both acicula penetrating epidermis; neuropodia with a supraacicular process. Notochaetae stout with distinct rows of spines and blunt tip. Neurochaetae more numerous and usually more slender; with distinct rows of spines distally and tips falcate or straight, either all bidentate with a subdistal secondary tooth or some bi- and some unidentate.

Remarks. In the Northeast Atlantic the genus Harmothoe might be confused with several other genera with less than 50 segments. The distinction from Acanthicolepis Norman in McIntosh, 1900 and Leucia Malmgren, 1867 can be problematic, since they differ only by the presence of 18 or 16 pairs of elytra, respectively. This makes correct identification of anterior fragments or juveniles of these genera rather difficult and therefore, they are also included in the following key to the Northeast Atlantic Harmothoe species (see also Figs. 1–5 ).

Harmothoe is easily distinguished from other short-bodied polynoid genera with cephalic peaks and lateral antennae inserted ventrally due to very obvious chaetal differences. A first group of genera differs by its neurochaetae: in Austrolaenilla Bergström, 1916 neurochaetae are stout with hairy tip; in Bylgides Chamberlin, 1919 they are slender and mostly taper to capillary tip; in Eucranta Malmgren, 1866 they are stout and some show a forceps-like tip; in Eunoe Malmgren, 1866 all are stout with unidentate tip; and in Robertianella McIntosh, 1885 they are stout with a bill-shaped tip. The latter genus differs additionnally by the absence of a neuropodial supra-acicular process. A second group of genera differs mainly by the presence of two kinds of notochaetae: in Gattyana McIntosh, 1897 notochaetae are stout with blunt tip and slender with capillary tip; and in Neolagisca Barnich & Fiege, 2000 they are stout with blunt tip and slender, tapering abruptly to a sharp, pointed tip.

Often confused with Harmothoe , but clearly distinguishable, are Subadyte Pettibone, 1969 and Malmgreniella Hartman, 1967 . In Subadyte neurochaetae have striking semi-lunar pockets and the only species present in the Northeast Atlantic, i.e. S. pellucida ( Ehlers, 1864) , differs further by the absence of cephalic peaks and a supra-acicular process. Also Malmgreniella can easily be differentiated due to the absence of cephalic peaks and its lateral antennae inserted terminoventrally (Note: In our opinion the generic affiliation of some Pacific species with cephalic peaks attributed to Malmgreniella by Pettibone (1993a) should be re-evaluated).

Distinguishing characters of the genera discussed here are summarised in Table 1 (see also Barnich & Fiege 2000 and 2003, Barnich et al. 2000 and 2006, Fiege & Barnich in press, Pettibone 1963, 1969, 1993a, and 1993b).

Figures

FIGURE 1. Identification characters of Harmothoe anoculata, H. ingolfiana, H. areolata, H. spinifera, H. antilopes, and H. imbricata.

FIGURE 2. Identification characters of Leucia violacea, Harmothoe fraserthomsoni, Leucia nivea, Acanthicolepis asperrima, Harmothoe aspera, and H. serrata.

FIGURE 3. Identification characters of Harmothoe impar, H. clavigera, H. rarispina, H. extenuata, H. fragilis, H. vesiculosa, H. abyssicola, and H. mariannae n. sp.

FIGURE 4. Identification characters of Harmothoe pokoui, H. bellani, H. evei, H. benthaliana, and H. longisetis.

FIGURE 5. Identification characters of Harmothoe fernandi n. sp., H. oculinarum, H. gilchristi, H. aequespina, H. glabra, and H. viridis.