Sternaspis londognoi, Salazar-Vallejo, 2017
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publication ID |
https://doi.org/ 10.6620/ZS.2017.56-32 |
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persistent identifier |
https://treatment.plazi.org/id/1B2187E0-1F15-6651-FC51-27C1B9052D88 |
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treatment provided by |
Felipe |
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scientific name |
Sternaspis londognoi |
| status |
sp. nov. |
Sternaspis londognoi View in CoL sp. nov.
( Fig. 5 View Fig )
urn:lsid:zoobank.org:act:9106E216-981A-4B96-A3A3-1EF1A2E9EC28
Sternaspis scutata View in CoL : Gilbert 1984:45.3-45.4, Figs 45.1, 45.2 (non Ranzani, 1817).
Type material: Southwestern Caribbean , Panama. Holotype ( LACM 5704 About LACM ) and paratype ( LACM 5705 About LACM ), Caledonia Bay, R.V. Velero, Sta. 2, 3 Apr. 1939, intertidal, O. Hartman, coll. (paratype 16 mm long, 10 mm wide, abdomen 11 mm long; shield left plate 2.5 mm long, 3.6 mm wide). Two paratypes ( LACM 5706 About LACM ), Caledonia Bay, R.V. Velero, Sta. 52, 25 Apr. 1939, 9 m, O. Hartman, coll. (15-17 mm long, 8 mm wide, abdomen 9-12 mm long; shield left plate 2.5-2.6 mm long, 3.0- 3.3 mm wide).
Additional material: Gulf of Mexico, Texas. Eight specimens ( USNM 43198), juveniles, off Galveston, Cruise PI-3, Sta. 12 (28°30'N, 94°37'W), 36 m, 4 Feb. 1966, C.J. Guice, coll. (3.0- 5.5 mm long, 1.5-3.0 mm wide, abdomen 2.0- 3.8 mm long, shield left plate 0.5-0.9 mm long, 0.5- 0.9 mm wide). Three specimens ( USNM 43199), juveniles, off Bolivar Peninsula, 5 m, Jan. 1968, C.J. Guice, coll. (4.0-5.0 mm long, 2.0-3.0 mm wide, abdomen 2.5-3.5 mm long, shield left plate 0.8-1.0 mm long, 0.7-1.1 mm wide).
Gulf of Mexico, Louisiana. Two specimens ( USNM 1437650), juveniles, R.V. Pelican, Sta. 90-2 (28°39.5'N, 91°06'W), 17 m, 11 Nov. 1938 (complete 3 mm long, 2 mm wide, abdomen 2 mm long, shield left plate 0.8 mm long, 0.7 mm wide).
Southwestern Caribbean, Colombia. One specimen ( UMML 22-1033), 6.5 km E Río Magdalena eastern delta, R.V. Pillsbury, Cruise 6806, Sta. 788 (11°08'N, 74°47'W), 155-157 m, 31 Jul. 1968 (juvenile, introvert slightly exposed; body 12 mm long, 6 mm wide, shield left plate 1.8 mm long, 2.2 mm wide).
Surinam. Two specimens ( UMML 22-1040), 140 km NE off Paramaribo, R.V. Pillsbury, Cruise 6806, Sta. 662 (06°49'N, 54°26.5'W to 06°51'N, 54°30'W), 44 m, 10 Jul. 1968 (macerated, larger one with anal tube exposed; body 18-25 mm long, 7-8 mm wide, shield left plate 2.3-2.4 mm long, 2.6- 3.0 mm wide). One specimen ( USNM 1185883), R.V. Coquette, Sta. 2 (06°23'N, 55°05.5'W), 27 m, mud, 11 May 1957 (introvert not exposed, genital papilla partly exposed; body 9.5 mm long, 7.5 mm wide).
Venezuela. Three specimens ( UMML 22- 1039), 2.8 km N off Cabo San Francisco, R.V. Pillsbury, Cruise 6806, Sta. 705 (10°45'N, 62°00'W to 10°45.5'N, 62°02.5'W), 77-86 m, 18 Jul. 1968 (juveniles, all with introvert exposed, one with anal tube exposed; body 9-13 mm long, 3-4 mm wide, shield left plate 1.5-1.6 mm long, 1.3-1.6 mm wide).
Panama. One specimen ( UMML 22-1042), Golfo de los Mosquitos, R.V. Pillsbury, Cruise 6607, Sta. 445 (09°01'N, 81°24'W), 344 m, 21 Jul. 1966 (body markedly contracted, introvert exposed, shield looks wider than posterior abdomen; body 17 mm long, 6 mm wide, shield left plate 4 mm long, 5 mm wide).
Description: Holotype ( LACM 5704) with body whitish, branchial filaments and shield orange, interbranchial papillae whitish ( Fig. 5A View Fig ). Integument finely papillose, body papillae not arranged in transverse groups. Body 16 mm long, 8 mm wide, abdomen 10 mm long; shield left plate 2.5 mm long, 3.3 mm wide.
Prostomium hemispherical, opalescent to translucent ( Fig. 5B View Fig ). Peristomium rounded, projected at the mouth and with papillae covering its surface; lateral mouth areas smooth, some papillae behind the prostomial lobe. Mouth circular, completely covered by minute papillae not extended up to first hook series. Pharynx partly exposed in paratype ( Fig. 5D View Fig )
First three chaetigers with 15-22 slender, bronze, falcate hooks, each with subdistal dark area ( Figs. 5B, D View Fig ). One pair of large, tubular, tapered genital papillae in intersegmental groove between segments 7 and 8, very long in one paratype ( Fig. 5F View Fig ). Pre-shield region with 7 segments; capillary chaetae not seen in holotype; non-type specimens with 1-2 capillaries along several segments.
Shield orange, with ribs and concentric lines ( Fig. 5C View Fig ); suture indistinct. Anterior margins angular, anterior depression shallow; anterior keels not exposed. Lateral margins rounded, expanded medially and posteriorly, finely crenulated. Fan barely reaching posterior shield corners, medially projected, denticulated; three paratypes with fan not expanded medially ( Figs. 5E View Fig , G-H), all with reddish central area.
Marginal chaetal fascicles include 9-10 lateral ones, chaetae in oval arrangement, and 8-9 posterior fascicles, chaetae in a slightly curved arrangement. Peg chaetae long, emerge from an extended fleshy cone; a small fascicle of delicate capillary chaetae emerge from the base of peg chaetae.
Branchial filaments orange, long, twisted; interbranchial filaments abundant, whitish. Branchial plates slightly divergent, expanded anteriorly; branchiae arranged in several series.
Variation: All introvert hooks have subdistal dark areas. Genital papillae can be very long but because they are delicate, they might be broken in the holotype. The shield plates are wider than long. Two paratypes have anal peduncles exposed. Juveniles have shields with plates longer than wide and become as long as wide when they are 11-13 mm long, and then progress to become wider than long; suture is visible throughout the shield, but lateral plates become fused as growth progresses.
Etymology: This species is being named after my good friend and colleague Dr. Mario H. Londoño-Mesa, from Universidad de Antioquia, Colombia, in recognition of his research papers on terebellid polychaetes, and for his continuous efforts for teaching in difficult conditions in his beloved country. The epithet is a noun in the genitive case, but the orthography has been modified to make it euphonic and resemble his first last name.
Remarks: Sternaspis londognoi sp. nov. resembles S. africana Augener, 1918 as redescribed elsewhere ( Sendall and Salazar-Vallejo 2013), because both have abundant, thin introvert hooks, and shields fused with fans medially projected and with crenulated margin. Their main differences rely on the relative pigmentation of introvert hooks, on the relative size of genital papillae, and on the relative depth of the anterior depression and development of posterolateral corners. In S. londognoi introvert hooks have a subdistal dark area, genital papillae are thicker and longer, and the anterior depression is shallow and the posterolateral corners are well-developed, whereas in S. africana introvert hooks do not have a subdistal dark area, their genital papillae are short and thin, the anterior depression is deep, and the posterolateral corners are not pronounced. In her report for the Allan Hancock Atlantic Expedition, Hartman (1944) did not include sternaspids, probably because the specimens were placed elsewhere.
Distribution: Gulf of Mexico and Caribbean Sea in shallow water to shelf depths (0-344).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.