Leitoscoloplos panamensis ( Monro, 1933 )

Dean, Harlan K. & Blake, James A., 2015, The Orbiniidae (Annelida: Polychaeta) of Pacific Costa Rica, Zootaxa 3956 (2), pp. 183-198 : 186-187

Leitoscoloplos panamensis ( Monro, 1933)

Figures 1 (D–F), 2 (B)

Haploscoloplos panamensis Monro, 1933:1045 –1046, Fig. 1 A–D.— Fauchald, 1977: 46. Not Hartman, 1957: 277, pl. 28, 1– 3 (= Scoloplos alaskensis ) Fide Mackie, 1987.

Leitoscoloplos panamensis: Mackie, 1987: 19 –20, Fig. 20.— Hernández-Alcántara & Solís-Weiss, 1999: 27; 2014: 146‒149.

Material examined. Gulf of Nicoya: Sta. 22, 9°48ˊ25″N, 84°52ˊ40″W, 22 m, muddy sand, 10 Jul 1980 (1); Sta. 29, 9°54ˊ55″N, 84°45ˊ15"W, 18 m, muddy sand, 27 Jan 1980 (1), 7 Jun 1981, 1 ( MZUCR); Bahia Culebra: Sta.

1, 10º35ˊ24.8″N, 85º39ˊ41.6″W, 1.5 m, 19 May 2011 (2); Sta. 2, 10º35ˊ51.8"N, 85º39ˊ24.7"W, 18 m, 19 May 2011 (2); Sta. 4, 10º35ˊ26.7″N, 85º39ˊ16.8"W, 6 m, 19 May 2011, 1 ( MZUCR); Sta. 21, 10º37ˊ12.7″N, 85º38ˊ31.2″W, 16 m, 19 May 2011 (3); Sta. 29, 9°54ˊ55″N, 84°45ˊ15″W, 18 m, muddy sand, 7 Jun 1981 (1). Jicaral, intertidal, 9º58ˊN, 85º06ˊW, mangrove roots Jan 1996, 1 ( MZUCR).

Description. All specimens incomplete, maximum thoracic width 0.18–0.74 mm ( Fig. 2 B). Prostomium conical, longer than wide, eyespots lacking; paired dorsolateral nuchal organs present. Peristomium subequal in length and width to first segment, about two-thirds prostomial length. Thorax 12–17 setigers long. Branchiae from setiger 9 in all specimens, short, papilla-like at first, increasing in length and width posteriorly.

Thoracic notopodial postsetal lobes triangular, increasing in length posteriorly; neuropodial postsetal lobes mammiliform in setigers 1‒9 of specimen with 17 thoracic setigers; bifurcate in subsequent thoracic setigers; mammiliform in setigers 1‒7, bifurcate in remaining thoracic setigers of specimens with 12 and 13 thoracic setigers ( Fig. 1 D). Single, small papilla on last 2‒3 thoracic setigers, 2‒3 papillae on subsequent 4‒5 abdominal setigers ( Fig. 1 E). Interramal cirri on first five abdominal setigers; accompanied by triangular notopodial postsetal lobe; neuropodial postsetal lobe bifurcate ( Fig. 1 E). Notopodial postsetal lobe widens, becoming foliaceous in midabdominal setigers ( Fig. 1 F), then longer and more narrow posteriorly; neuropodial postsetal lobe reduced, only weakly bifurcate in posterior abdominal setigers, lateral branch smaller than medial; subpodial flange present ( Fig. 1 F).

Notosetae and neurosetae camerated capillaries throughout, densely packed in thoracic parapodia, reduced to 2‒3 weakly camerated capillaries in abdominal neuropodia ( Fig. 1 F); furcate setae absent.

Remarks. This species was originally described by Monro (1933) from shallow water muds in Pacific Panama. The thorax was 17 setigers long and the branchiae were reported to begin on setiger 12; however, Mackie (1987) examined Monro’s type material and reported that the branchiae actually began on setiger nine which is true of the Costa Rica specimens. L. panamensis is most similar to L. bifurcatus and L. multipapillatus in possessing branchiae from setiger nine. L. panamensis lacks the numerous stomach papillae of L. multipapillatus and has subpodial papillae which are lacking in L. bifurcatus .

Distribution. This species has been previously reported from the Pacific coast of Panama ( Monro 1933) and the Gulf of California, Pacific Mexico ( Hernández-Alcántara & Solís-Weiss 1999, 2014).

Figures

FIGURE 1. Leitoscoloplos multipapillatus: A, Posterior thoracic parapodium, posterior view; B, Station 29, Gulf of Nicoya specimen, thoracic setiger, anterior view; C, Station 1, Bahia Culebra specimen, posterior end and pygidium. Leitoscoloplos panamensis: D, Station 29, Gulf of Nicoya specimen, thoracic setiger, anterior view; E, Station 29, Gulf of Nicoya specimen, anterior abdominal setiger, anterior view; F, Station 28 Jun, Gulf of Nicoya specimen, posterior abdominal setiger, anterior view. Scale bars: A ‒ F = 100 µm. br = branchiae, ic = interramal cirri, neL = neuropodial lamellae, noL = notopodial lamellae, p = prostomium, per = peristomium, sp = subpodial papillae, vc = ventral cirri.

FIGURE 2. Leitoscoloplos multipapillatus: A, Anterior end, lateral view. Leitoscoloplos panamensis: B, Station 29, Gulf of Nicoya specimen, anterior end, lateral view. Leitoscoloplos pugettensis: C, Station 22, Gulf of Nicoya specimen, anterior end, lateral view; D, Station 9, Bahia Culebra specimen, midbody abdominal setiger, anterior view; E, Station 9, Bahia Culebra specimen, posterior abdominal setiger, posterior view. Leodamas hamatus n. sp.: F, Holotype, posterior thoracic setiger, anterior view; G, Holotype, Posterior notopodial emergent hook. Scale bars: A, C = 1000 µm, B = 500 µm, D, E = 100 µm, F = 50 µm G = 10 µm.