Sicafodia stylos, Just, 2004
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publication ID |
https://doi.org/ 10.24199/j.mmv.2004.61.5 |
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persistent identifier |
https://treatment.plazi.org/id/03A487FB-8D18-4B68-FF46-2CFFFD011164 |
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treatment provided by |
Felipe |
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scientific name |
Sicafodia stylos |
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sp. nov. |
Sicafodia stylos View in CoL sp. nov.
Figures 1–4 View Figure 1 View Figure 2 View Figure 3 View Figure 4
Material examined. Holotype. Female with developing ovaries, 3.7 mm. Australia, eastern Tasmania, off Freycinet Peninsula , 41° 57.50'S, 148° 37.90'E, 400 m, coarse biogenic rubble, mud, WHOI epibenthic sled, M.F. Gomon et al., RV Franklin, 27 Jul 1986 (stn SLOPE-48), NMV J23915 About NMV (condition: antennae, some pereopods and tip of some uropods broken). GoogleMaps
Paratypes (5 specimens, all from Australia). Same data as holotype, NMV J23916 About NMV (female A, with apparent traces of broken oostegites; condition: antennae and most pereopods and uropods broken, telson missing). Eastern slope of Bass Strait, 38° 21.90'S, 149° 20.00'E, 1000 m, WHOI epibenthic sled, G.C.B. Poore et al., RV Franklin, 23 July 1986 (stn SLOPE-32), NMV J23917 About NMV (female B, with fully developed oostegites, 4.6 mm; condition: antennae, some pereopods and uropods broken), NMV J23918 About NMV (female C, with fully developed oostegites; condition: half specimen, everything posterior to pereonite 6 missing, antennae and most pereopods broken), NMV J23919 About NMV (female D, with fully developed oostegites; condition: half specimen, everything posterior to pereonite 7 missing, antennae and most pereopods broken). Eastern Bass Strait slope, 67 km S of Point Hicks, 38° 23.78'S, 149° 17.02'E, 1119–1277 m, fine mud, WHOI epibenthic sled, G.C.B. Poore et al., RV Franklin, 25 Oct 1988 (stn SLOPE-67), NMV J23920 About NMV (1 specimen, condition: antennae, all pereopods and most of uropods broken) GoogleMaps .
Description. Cephalon depth approximately 2.5 times midlateral length. In lateral view cephalon tapering towards right angled ventral corner. Ocular lobes broadly rounded, continuing in nearly straight line to ventral corner. Eyes absent. Rostrum about as long as deep in lateral view, apex rounded triangular, approximately half length of non-rostral part of cephalon, ventrally forming a narrow angle with elongate, convex frons part of cephalon. Epistome short, unproduced.
Pereonite 1 as long as its anterior depth, as long as 2 and 3 combined. Pleosome dorsal length equalling combined length of pereonites 2–7, pleonites of equal length.
Coxal plates 1–4 with smoothly rounded ventral margin; plates 1–3 of subequal length when flattened, (appear to increase in length from 1 to 3 in Fig.1 View Figure 1 habitus, due to 1 and 2 curving slightly inwards), of rounded rectangular shape but increasing in width from 1 to 3; coxa 1 length:width 1.25, coxa 2 length:width 1.20, coxa 3 length:width 1.0, coxa 4 length:width 0.70, with rounded angular posterior projection and weak concavity posterior to projection; coxa 5 with lobes equally deep, anterior lobe wider, evenly rounded, posterior lobe rounded rectangular; coxa 6 similar to 5, but posterior lobe approximately third deeper than anterior lobe; coxa 7 an evenly rounded semicircle. Pleonal sideplates with smooth margin; plate 1 with weakly angular apex, 2 and 3 rounded.
Antenna 1, peduncular article 1 as long as 2 and 3 combined, approximately 10% longer than lateral width, articles 2 and 3 of subequal length, both somewhat telescoped into preceding article, article 3 with lateral apical margin extended beyond insertion of accessory flagellum; accessory flagellum approximately half length of flagellar article 1, distally tapering, with 1 apical and 1 subapical setae; article 1 of flagellum approximately two-fifths as wide as long, with single-field callynophore composed of 4–5 irregular rows of aesthetascs, article 2 and 3 with 2 distal rows of similar aesthetascs. Antenna 2 with broad, apically pointed antennal cone; peduncular article 4 approximately twice as long as wide, reaching to apex of flagellar article 1 of antenna 1. (Antennae otherwise broken in all specimens, but the shape of the proximal parts known suggests that the flagellum of both antennae is simple, multiarticulate). Upper lip approximately 2.5 times longer than wide at base (anterior view), narrowing in middle, tapering towards bilobed apex, apical notch forming a narrow angle. Mandibles styliform distal to insertion of palp, reaching to apex of upper lip; left mandible with irregularly notched apex, lacinia mobilis a long slender rod terminating in strongly oblique cutting edge with 6 or 7 small denticles; right mandible with 3 blunt teeth apically, lacinia mobilis quarter to half length of left lacinia mobilis, with bifid apex; strong palp inserted in proximal third of mandibular body, reaching slightly beyond apex of mandible, article 1 as long as broad, article 2 approximately 4 times longer than broad with 2–3 distal setae, article 3 approximately three-quarters length of 2, with up to 4 setae on posterior margin and approximately 4 apical setae, lateral surface partly covered with fine setules. Lower lip with styliform lobes, lobes finely setose apically not quite reaching apex of mandibles; mandibular lobes short, slender, pointing directly backwards. Maxilla 1 outer plate approximately 11 times longer than greatest width; distal 9 spine-like setae falling into three groups: 2 apical setae (one coarsely serrate along entire length, one finely serrate in distal quarter), 5 setae closely set on strongly oblique margin (regularly denticulate in distal half), 2 poorly articulating, flattened more proximal setae closely adpressed to medial surface of plate, coarsely and irregularly serrate along entire margin; inner plate approximately third length of outer, slender, cylindrical, tapering towards rounded apex, without setae. Maxilla 2 outer plate approximately 9 times longer than greatest width, with tuft of approximately 6 unequally long apical setae; inner plate approximately 80% length of outer, with 4 apical simple setae and 3 short, subapical medial bi- or trifid setae. Maxilliped palp article 1 ovoid, approximately 50% longer than wide, article 2 approximately 80% length of 1, of similar shape, article 3 as long as 1 and 2 combined, third width of 2, approximately 9 times longer than wide with 3 or 4 groups of 2 or 3 setae on midlateral surface and tufts of apical and subapical setae; outer plates broad in proximal third, tapering towards truncate apex, apex with row of at least 8 blunt, rodlike setae evenly decreasing in length from medial to penultimate lateral seta, lateralmost seta stouter than the rest, approximately as long as medialmost one, curved mediad, with denticles in distal quarter, (because of the natural forward folding of outer plates around remaining mouthparts, Fig. 2C View Figure 2 mxp dv, the lateralmost, denticulate seta, Fig. 2A View Figure 2 mxp op, is functionally in a medial position, cf. above); inner plates nearly as long as outer plates, each plate slender with nearly parallel margins, terminating in bluntly pointed apex with what appears to be glandular tissue in terminal part ( Fig. 2C View Figure 2 mxp ip), plates with small opposing notch in medial margin proximal to ‘gland’, each plate laterally, between notch and ‘gland’, with tuft of 4 or 5 inward curving setae decreasing in length from lateral to medial.
Gnathopod 1 basis approximately 4 times longer than broad, as long as merus and carpus combined, with anterior longitudinal concavity to receive article 5 when fully folded back; ischium approximately twice as long as lateral width; merus triangular, anteriorly pointed, approximately as long as ischium, with carpus inserted on anterior margin; carpus slender, twice as long as merus, with parallel margins, approximately 6 times longer than wide, unarmed; propodus approximately 65% longer than carpus, 12 times longer than broad at base, slightly curved and faintly tapering distally, with a few short posterior setae; dactylus weakly curved, approximately sixth length of propodus, with posterior tooth near base of stout, curved unguis, 1 straight, simple seta level with tooth and 2 curved, blunt, simple setae at posterior base of and adpressed to unguis.
Gnathopod 2 little more than half the length of 1, without elongate elements; carpus approximately 80% the combined length of ischium and merus, triangular, approximately 50% longer than lateral distal width, posterodistal lobe setiferous, not projecting along propodus; propodus approximately 10% longer than carpus, moderately curved, tapering distally, with 4 or 5 posterior groups of stiff, pectinate setae, anterior margin with group of similar setae at distal two-thirds; dactylus half length of propodus, similar to that of gnathopod 1 but with 2 small midposterior teeth.
Pereopods 3 and 4 similar, slender, approximately 4 times longer than respective coxal plates; merus and carpus subequal in length, combined as long as basis; propodus twice as long as carpus; merus, carpus and propodus with a few posterior and anterior small setae, propodus with small posterodistal robust seta; dactylus half length of propodus, nearly straight, length approximately eight times width at base. Pereopods 5–7 apparently alike (pereopod 6 the only entire limb known, hence relative lengths of 5–7 not known, but probably of subequal length), with posteriorly expanded distally rounded basis, posterior margin smooth with scattered setules, with midlateral and anterolateral ridges; at least pereopod 6 approximately third longer than pereopods 3 and 4, but otherwise of similar shape and proportions, carpus posterodistally and propodus posteriorly with groups of slender robust setae.
Pleopods strong, alike; peduncle approximately twice as long as wide (posterior view), with 2 mediodistal coupling hooks; subequal rami as long as peduncle, proximal part of rami with opposing surfaces excavate, outer ramus with posterior proximal locking projection.
Urosomite 1 as long as 2 and 3 combined; urosomite 2 dorsal length approximately quarter that of elongate 3; urosomite 3 dorsally flattened to slightly concave in transverse section. Uropods 1 and 2, peduncles with lateral robust setae; uropod 1 overreaching 2 and outer ramus of 3, (tip of uropod 1 rami broken in all specimens, but proportions between rami and peduncle probably approximating those in uropod 2); uropod 2 shorter than 1, reaching nearly to tip of outer ramus of 3, outer ramus as long as peduncle, inner ramus approximately 40% longer than outer; uropod 3 biramous (inner ramus lost in all specimens, but presence indicated by socket and musculature), peduncle as long as wide, reaching to tip of telson, outer ramus approximately 5 times longer than peduncle; rami of all uropods slender lanceolate, without terminal seta(e), but apparently all with a few small lateromarginal setae, margins finely serrate. Telson approximately 10% broader than long, reaching to distal margin of peduncle of uropod 3, quarter cleft in open V-shape; lobes rounded, each with 2 distolateral marginal teeth, 2 or 3 small pappose setae level with teeth and 1 long similar seta at mid-surface.
Size. Largest female, 4.7 mm. Male not known.
Etymology. The species name is derived from the Latin stylus meaning pointed instrument or pen, and os meaning mouth, alluding to the long, pointed mandibles. Noun in apposition.
Distribution. South-eastern Australia, 400–1277 m depth.
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.
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