Melinna elisabethae McIntosh, 1885

Gunton, Laetitia M., Zhang, William, Kupriyanova, Elena K. & Hutchings, Pat A., 2023, New Species of Melinna (Melinnidae, Annelida) from the Australian Abyss with Comments on M. albicincta, M. cristata and M. elisabethae, Records of the Australian Museum (Rec. Aust. Mus.) 75 (3), pp. 125-154 : 143

publication ID	https://doi.org/ 10.3853/j.2201-4349.75.2023.1803
DOI	https://doi.org/10.5281/zenodo.10982410
persistent identifier	https://treatment.plazi.org/id/03A9585E-FFDA-FFC4-5CC6-D6B96770F8DB
treatment provided by	Felipe
scientific name	Melinna elisabethae McIntosh, 1885
status

Treatment

Melinna elisabethae McIntosh, 1885 View in CoL

Figs 13–15 View Figure 13 View Figure 14 View Figure 15 ; Tables 4, 5

Melinna elisabethae McIntosh, 1885: 438 View in CoL ; 1914 106–107 (in part).

For complete synonymy see Mackie & Pleijel, 1995.

Material examined. AM W.21793, 4 specimens, including prepared for SEM, Cleveland , Tees Bay, England (54°36'N 1°48'W), gravelly mud/rock, 44 m, coll. Analytical & Environmental Services, 7 September 1984 GoogleMaps .

Remarks

The original description by Mackie & Pleijel (1995) only provided line drawings, we give additional information based on light and SEM images.

Prostomium welldeveloped and divided into anterior and posterior parts, anterior part trilobed ( Fig. 15B View Figure 15 ), posterior part raised triangular glandular with anterior margin bearing longitudinal slits ( Fig. 15B View Figure 15 ). Buccal tentacles numerous and equal in length to the branchiae ( Fig. 13B View Figure 13 ). Four pairs of branchiae annulated with distal surface exhibiting cilia patches ( Fig. 14A,C View Figure 14 ). Branchiae circular in crosssection, anterior pair showing 40% of basal fusion and outer pair 20% fusion ( Figs 13B,C View Figure 13 , 14C View Figure 14 ). One pair of dorsal hooks strongly curved and with pointed tips ( Figs 13B,D,E View Figure 13 , 14B,C View Figure 14 ), solid without internal canal. Dorsal membrane with about 12 triangular projections on anterior margin ( Figs 13E View Figure 13 , 14A View Figure 14 ). First segment achaetous ( Fig. 14A View Figure 14 ) with crenulated ventral margin ( Fig. 15B View Figure 15 ). Segments 2–5 with acicular neurochaetae arranged in elongated tori, progressively inserted more laterally ( Fig. 13B,C View Figure 13 ). From segment 6 neuropodia with uncini continuing to pygidium. Notopodia present from segment 4, initially very small with short notochaetae, then progressively becoming larger, more laterally inserted and welldeveloped by segment 7 ( Figs 13D View Figure 13 , 14A View Figure 14 , 15C View Figure 15 ) and on all subsequent ones. Notochaetae arranged in two tiers ( Fig. 14H View Figure 14 ) with tips of longer ones curved ( Fig. 15A View Figure 15 ) and with blades finely ornamented ( Figs 14F,H View Figure 14 , 15A,E View Figure 15 ). Notopodia globular with posterior lobe longer than anterior one ( Fig. 14D,E,F View Figure 14 ) and well separated from neuropodia ( Figs 14E View Figure 14 , 15C View Figure 15 ). Thoracic neuropodia raised glandular tori slightly curved, bearing about 26 uncini ( Fig. 14E View Figure 14 ). Thoracic uncini with a single row of four teeth with ornamentation on lateral face and becoming marked and behind anterior tooth strongly ornamented with small teeth ( Figs 14G View Figure 14 , 15D,F View Figure 15 ). Abdominal rudimentary notopodia not observed as in Mackie & Pleijel (1995), specimens very small and thin ( Fig. 15G View Figure 15 ).Abdominal neuropodia welldeveloped but not elevated, anteriorly bearing four teeth arranged in a single row ( Fig. 15H,I View Figure 15 ). Terminal anus bounded by pair of large lateral lobes and several smaller lateral ones ( Fig. 13a View Figure 13 ) and lacking anal cirri. Methyl blue stain shows extensive ventral glandular areas ( Fig. 13F View Figure 13 ). Tube with attached shell fragments on anterior end and rest of tube made of smaller sand grains and mud ( Fig. 13G View Figure 13 ).