Lumbriclymene interstricta comb . nov . with a taxonomic key and a catalogue for all species of Lumbriclymene ( Maldanidae , Polychaeta )

In this paper, we transfer Nicomache interstricta Ehlers, 1908 to Lumbriclymene Sars, 1872 based on a redescription of the type-specimen. We provide new illustrations for the species and new diagnostic features for the genus. Lumbriclymene interstricta (Ehlers, 1908) comb. nov. has 19 chaetigerous segments and four pre-anal achaetous segments; a prostomium rounded anteriorly, forming a slightly arched dorsal keel; semi-circular nuchal grooves; one acicular spine on chaetigers 1-4; and a small pygidium, with the anal pore bearing many small papillae. In addition, we compare the species with other subfamilies and genera of Maldanidae. We also provide a taxonomic key for all species presently included in Lumbriclymene. Finally, we provide a world catalogue for Lumbriclymene, containing synonyms and main references.

Lumbriclymeninae Malmgren, 1867 contains four valid genera: Lumbriclymene Sars, 1872, Praxillura Verrill, 1880, Clymenopsis Verrill, 1900and Lumbriclynenella Arwidsson, 1911.Characters used to identify species of Lumbriclymene are the shape of the prostomium, the shape of the nuchal grooves, the number of spines per bundle on the anterior chaetigers, the shape of the chaetae, the shape and number of achaetous pre-anal segments, and the structure of the anal funnel.

MATERIAL AND METHODS
The type material that we examined was obtained from Museum für Naturkunde aus Berlin -Nicomache interstricta Ehlers, 1908 (Holotype 4535, Deutsche Tiefsee-Expedition Valdivia Station 203).We redescribed the type species using a Zeiss stereomicroscope.Chaetae, uncini, and acicular spines were observed with an Olympus BX41 compound microscope.All illustrations were drawn using a camera lucida.Measurements are in millimeters.
We provide a catalogue of all species of Lumbriclymene previously described in the literature (Appendix 1).The following information is included: species names (in alphabetical order), authority for each name, publication year, number of pages and figures (when available), type locality (including coordinates when available), and geographical distribution.In some cases, we have included remarks on possible taxonomic issues.Synonyms (when present) are listed below the original name, including as many references for each as possible.The references contain complete citations, including all authors who have described new taxa.
Redescription.The type-specimen is fragmented into three pieces: an anterior region measuring 45 mm in length and 1 mm in width, having seven very long chaetigerous segments, a median portion with a length of 5 mm and a width of 1 mm, with three short chaetigerous segments, and a posterior portion measuring 46 mm in length and 1 mm in width, having nine long chaetigerous segments.Specimen with 96 mm in total length, with 19 chaetigerous segments, and four achaetous pre-anal segments.Head with 0.6 mm in length; posterior end with four achaetous pre-anal segments, and a pygidium without an anal cup, with 0.2 mm in length.The body is basically cylindrical, with elongate segments.
Neuropodia of first four chaetigers have a simple acicular spine, which is strong, pointed, and honey-colored (Fig. 3).Chaetiger five with a short collar.From chaetiger five towards posterior region, the neuropodia have tori, which are present up to chaetiger 19.Each uncinus has 2-4 teeth on the main fringe, and 5-6 smaller teeth slightly below this fringe.Below the rostrum arise five thin long barbules (Fig. 4).Each hook is perpendicular to the body wall, with a long and curved posterior shaft, and a prominent manubrium on the posterior half.Notopodia of chaetigers 1-19 with tufts of long and fine capillary chaetae, which are limbate, with base ruffled (Fig. 5).
There are four achaetous pre-anal segments, which are thin and only slightly inflated.Pygidium cylindrical, short, with numerous transversal striae, positioned very close to each other.Anus terminal, with many small and thick papillae (Fig. 6).
LANA (1983) suggested to transfer Lumbriclymene constricta Wesenberg-Lund, 1948 to Clymenopsis constricta (Wesenberg-Lund, 1948), based on the presence of a collar on chaetiger four, and due to the restriction of the acicular spines to the first three chaetigers.
The position of the anus and the shape of the pre-anal structures provide the main diagnostic characters for the distinction of the species of Lumbriclymene.The number of chaetigerous is constant for all species of this genus (LANA 1983).The number of achaetous pre-anal segments, the shape of the prostomium, the shape of the nuchal grooves, and the number of acicular spines vary only slightly within this taxon.
Nicomache interstricta cannot belong to any of these subfamilies, neither to Nicomache Malmgren, 1866, of Nicomachinae, whose species have a truncate anal plate inserted into an anal cup (DE ASSIS et al. 2007a, b).Therefore, based on the shape of the anal plate, we transfer N. interstricta to Lumbriclymene, which belongs to Lumbriclymeninae, under the new combination Lumbriclymene interstricta comb.nov.. LANA (1983) recognized three species complexes within Lumbriclymene.The first complex includes species with a terminal anus (Fig. 7): L. nasuta, which has a cylindrical pygidium with a tapered end, and an anal pore covered by one large, short, ventral papilla, which is larger than the dorsal papilla; L. campanulata, which has a pygidium with tapered end, and no papillae covering the anal pore; L. japonica, with a cylindrical pygidium with an elliptical end, and with an anal pore covered by many small papillae; and L. interstricta comb.nov., which has a cylindrical pygidium with an elliptical end, and an anal pore covered by numerous short papillae (ARWIDSSON 1906, HARTMAN 1960, 1965, WESENBERG-LUND 1948, LANA 1983).
The second complex includes species with a sub-terminal dorsal anus (Fig. 8): L. cylindricauda and L. fusca, which have a cylindrical pygidium with a narrow end, and an anal pore covered by a single ventral papilla (SARS 1872, ARWIDSSON 1906, DAY 1967, LANA 1983).
The third complex includes species with a dorsal anus (Fig. 9): L. australis and L. minor, both with a pygidium which tapers to a distal end, but without papillae covering the anal pore; and L. lineus and L. noemia, both with a pygidium with a pointed distal end, and with an anal pore covered by a medioventral small papilla (ARWIDSSON 1906, HARTMAN 1960, WESENBERG-LUND 1948, LANA 1983).
Most species are only known from their type localities, whereas only L. minor and L. cylindricauda have a broad geographical distribution (Fig. 10).