Austrodecus taylorae Staples 2019
- Dataset
- Pycnogonids (Arthropoda, Pycnogonida) from the Southwest Indian Ridge
- Rank
- SPECIES
- Published in
- Staples, David A. (2019): Pycnogonids (Arthropoda, Pycnogonida) from the Southwest Indian Ridge. Zootaxa 4567 (3): 401-449, DOI: 10.11646/zootaxa.4567.3.1
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Pycnogonida
- order
- Pantopoda
- family
- Austrodecidae
- genus
- Austrodecus
- species
- Austrodecus taylorae
description
Description. Male holotype. Trunk (Fig. 11 A, B. Plates 3 H, 4 B) papillose, quite transparent, segments 1 to 4 with dorsomedian tubercles, height each little more than half depth of trunk, those on segments 2 and 4 slightly shorter than those on segments 1 and 3, margins of tubercles uneven; lateral processes smooth, separated by about half basal width, diverging distally. Ocular tubercle tall, height almost equal to 60 % of trunk length, inclined forward, over-reaching base of proboscis, tapering from broad base to narrow truncate tip, surface of basal part coarsely rugose; four eyes, unpigmented. Proboscis 30 % longer than trunk, typical of genus, down-curved, annulated distally, basal part inflated, smooth, jaws vertically bilateral. Abdomen (Fig. 11 C) unarticulated at base, surface coarsely rugose, length about 35 % of trunk length, carried horizontally, tapering slightly distally. Chelifores absent. Palp (Fig. 11 E) five-segmented, attached to lateral extension of cephalon, segment 1 longest segment, with 1 or 2 strong inward-facing curved spines, segment 3 next longest, greater than half length segment 1, with six inwardfacing curved spines of similar shape and size. Oviger (Fig. 11 F) four-segmented, attached to ventral extension of cephalon, second segment with strong recurved spine on distal margin, segment 4 longest, constricted at tip and accompanied by several spines. Third leg: (Fig. 11 D) femur widest and longest segment, single mid-ventral femoral cement gland duct legs 3 and 4 only, conical, height little more than one-third width of femur, tibia 1 longer than tibia 2, tibia 2 more setose ventrally than other segments, femur with single long dorsodistal hair-like spine on low process, first coxae with prominent dorsodistal digitiform tubercles in the order of 1: 2: 2: 1, coxa 2 longer that coxae 1 or 3, third coxa with a distinctly bifurcate tubercle about one-third the height of those on coxa 1 (Fig. 11 I), tarsus short, with several median spines and two longer dorsolateral spines, propodus gently curved, heel absent, sole lined with about ten short spines, without major heel spines, terminal claw about 40 percent of propodus length, auxiliary claws almost half length main claw, flared outward. Gonopores not evident. Measurements of holotype (mm). Trunk length (frontal margin of cephalic segment to tip of 4 th lateral process), 0.784; width across 2 nd lateral processes, 0.400; proboscis length (dorsal), 1.016; abdomen length (lateral), 0.280; height ocular tubercle (lateral), 0.456. Third leg: coxa 1, 0.120; coxa 2, 0.128; coxa 3, 0.088; femur, 0.480; tibia 1, 0.440; tibia 2, 0.368; tarsus, 0.048; propodus, 0.280; claw, 0.112; auxiliary claws, 0.048. Palp: seg. 1, 0.576; seg 2, 0.080; seg. 3, 0.304; seg. 4, 0.040; seg. 5, 0.032. Oviger: seg. 1, 0.032; seg. 2, 0.040; seg. 3, 0.032; seg. 4, 0.088.
description
Figure 11 A – I; Plates 3 H; 4 A
discussion
Remarks. The basal part of ocular tubercle surface is particularly rugose with tiny pyramid-shaped projections. There is variability in the shape of oviger segment 4 which may be age dependent. In the holotype there is a strong constriction near the tip accompanied by one or two small spines (Fig. 11 F) whereas oviger segment 4 of one paratype is without apparent constriction (Fig. 11 G) but spination is similar. The fourth oviger segment of one smaller (less mature?) male is shorter, slightly ovate and without distal constriction (Fig. 11 H).
etymology
Etymology. Named for Dr Michelle Taylor, whose drive, direction and organization of all biological aspects contributed significantly to the efficient operation of the voyage.
materials_examined
Material examined. Holotype, male (NHMUK 2018.24), Southwest Indian Ocean, Atlantis Bank, 32 ° 42.86´S, 57 ° 16.34´E, ROV, 750 m, specimen JC 066 - 4213 C, stn 8.29, mooring site, on net containing Mango wood, 14 December 2011. Paratype. One male (NHMUK 2018.25), same collection details as for holotype. Two males (NHMUK 2018.26), Southwest Indian Ocean, Atlantis Bank, 32 ° 42.86´S, 57 ° 16.34´E, ROV, 750 m, specimen JC 066 - 4214 C, stn 8.29, mooring site, on net containing Mango wood, 14 December 2011.
Name
- Homonyms
- Austrodecus taylorae Staples 2019