Leitoscoloplos multipapillatus Hernandez-Alcantara & Solis-Weiss 2014
Creators: name: Dean, Harlan K.
name: Blake, James A.
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Orbiniidae
Leitoscoloplos
Leitoscoloplos multipapillatus

description: Leitoscoloplos multipapillatus Hernández-Alcántara & Solís-Weiss, 2014
Figures 1 (A–C), 2 (A), 4 (A)
Leitoscoloplos multipapillatus Hernández-Alcántara & Solís-Weiss, 2014:143 ‒146.
Material examined. Gulf of Nicoya: Station (STA.) 24, 9°49ˊ25″N, 84°41ˊ20″W, 11 m, sand, 1 Oct 1980 (1). STA 29, 9°54ˊ55″N, 84°45ˊ15"W, 18 m, muddy sand, 1 Oct 1980 (1); 6 Jul 1980 (2); 4 Apr 1982 (1). STA. 30, 9°54ˊ40″N, 84°45ˊ50″W, 18 m, muddy sand, 27 Jan 1981 (1). Bahia Culebra: STA. 1, 10º35ˊ24.8″N, 85º39ˊ41.6"W, 1.5 m, 19 May 2011 (2).
Description. Complete specimen 21.9 mm long, 0.61 mm maximum thoracic width for 76 setigers (Fig. 1 A, 2A); incomplete specimens maximum thoracic width 0.60–0.66 mm. Prostomium conical, longer than wide; eyespots absent; paired dorso-lateral nuchal organs present. Peristomium approximately one-half prostomial length, subequal to first setiger. Thorax with 15–19 setigers, widest in middle. Branchiae from setiger 9, short, triangular at first, becoming longer and more robust in posterior thoracic setigers each branchial pair located along dorsal mid-line. Thoracic parapodia weakly developed as low ridges; neuropodial postsetal lobes triangular, those of notopodia narrow; postsetal lobes increasing in length along thorax, subequal to setal length in posterior thoracic setigers; conical ventral cirrus present (Figs. 1 A, 4A). Stomach papillae present in the posterior thoracic and anterior abdominal region, on setigers 14–19 of 17 thoracic setiger specimen, on setigers 17–22 of 18 and 19 thoracic setiger specimens respectively, and on setigers 14–18 on 15 thoracic setiger specimen; maximally 12 papillae per setiger (Fig. 4 A). Abdominal notopodial postsetal lobes subequal to branchiae, wide with narrow distal region; neuropodial postsetal lobes bifid, lateral branch approximately one-half median branch length; welldeveloped subpodial flange ventral to neuropodial lobe (Fig. 1 B). Interramal cirri usually present on first several abdominal setigers; larger specimen with interramal cirri on last two thoracic setigers and first five abdominal setigers, those on thoracic segments actually emerging from superior border of notopodial pre-setal lobe. Posterior end slightly widened with approximately 12 closely spaced, dorso–ventrally flattened segments, pygidium scoop– shaped (Fig. 1 C).
Notosetae and neurosetae all camerated capillaries; thoracic neuropodia with row of longer capillaries and row of shorter capillaries in upper region of fascicle, lower region with double row of many short setae (Fig. 1 A); abdominal notopodia with 6–8 long capillaries, neuropodia with 3–5 long capillaries; furcate setae absent (Fig. 1 B).
Remarks. Based on the number of setigers in the thorax and first appearance of the branchiae, L. multipapillatus is most similar to L. panamensis (Monroe, 1933), L. mammosus Mackie, 1987 and M. bifurcatus (Hartman, 1957). L. panamensis has a 17 setiger thorax and branchiae from setiger 9, but the thoracic neuropodial postsetal lobes are bifurcate in L. panamensis. Additionally, a single subpodial papilla occurs on three or four posterior thoracic segments with two on the last thoracic segment of L. panamensis while L. multipapillatus has numerous ventral papillae (stomach papillae) on both posterior thoracic and anterior abdominal segments. L.
bifurcatus has 20–21 thoracic setigers and branchiae from setigers 8‒9 but this species differs from L. multipapillatus in having bifurcate thoracic neuropodial lobes in posterior thoracic setigers and lacking stomach papillae. L. mammosus also has branchiae from setigers 9–11 but only has 14–15 thoracic setigers (Mackie 1987). L. mammosus also lacks stomach papillae and has a long, digitate (rather than foliaceous) notopodial lobe in abdominal setigers.
A ventral fringe of stomach papillae on the last several thoracic and first several abdominal setigers has been reported in several genera of orbiniids including Phylo, and Orbinia (Blake 1996). In his review of the genus Leitoscoloplos Mackie (1987) reported that L. obovatus Mackie, 1987 was the only member of the genus with stomach papillae on the last several thoracic setigers with a single papilla located some distance from the neuropodial lobe. This single papilla, however, represents a subpodial lobe rather than stomach papillae which are numerous and extend as a band of papillae transversely across the ventrum (Blake 1996). Eibye Jacobsen (2002) later described two species from the Andaman Sea in the Indian Ocean with a well-developed array of stomach papillae, L. mackiei Eibye Jacobsen, 2002 and L. papillatus Eibye Jacobsen, 2002. Both differ from L.
multipapillatus in the length of the thorax and first occurrence of branchiae with L. mackiei having 17 thoracic setigers with branchiae beginning on setiger 13 and L. papillatus having a thorax of 14–15 setigers with branchiae beginning on setigers 9–11.
L. mackiei has up to six stomach papillae on posterior thoracic setigers while there are only one or two subpodial papillae on anterior abdominal setigers. L. papillatus has up to seven stomach papillae but they are found only on the abdomen. Both of these species differ from L. multipapillatus in that it has up to 12 stomach papillae per segment and a large number of stomach papillae occurring on both thoracic and abdominal setigers.
Distribution. This species was recently described by Hernández-Alcántara & Solís-Weiss (2014) from shallow subtidal waters in fine to muddy sands in the Gulf of California in eastern Pacific Mexico. It is known from the Gulf of Nicoya and Bahia Culebra on the Pacific coast of Costa Rica in sand and mud/sand sediments.
description: Published as part of Dean, Harlan K. & Blake, James A., 2015, The Orbiniidae (Annelida: Polychaeta) of Pacific Costa Rica, pp. 183-198 in Zootaxa 3956 (2) on pages 184-186, DOI: 10.11646/zootaxa.3956.2.2, http://zenodo.org/record/237218