Petalosarsia longirostris Jones, 1973

Mühlenhardt-Siegel, Ute, 2014, Deep-sea Bodotriidae, Diastylidae and Pseudocumatidae (Cumacea, Crustacea) from the southeastern Atlantic, Zootaxa 3815 (3), pp. 301-341 : 336-337

Petalosarsia longirostris Jones, 1973

( Figures 26–28 )

Material. ZAIANGO KGS #17: 1 non-ovigerous female (dissected) MNHN-IU-2012-1357.

Distribution. SW of Dakar, Senegal 1624 – 2185 m depth; Angola Basin, 1399 m.

Remarks. The non-ovigerous female ( Fig. 26 ) in the Ifremer collection is a very small specimen (2 mm long), comparable to the type material, an ovigerous female of 3 mm length. The carapace is smooth and slightly elevated behind the frontal lobe as described by Jones (1973). The pseudorostral lobes are relatively long (0.5 times as long as the rest of carapace) in the present specimen and the holotype. However, the siphonal tube is almost as long as the pseudorostrum and not mentioned by Jones (1973).

The antennal notch (shallow), the anterolateral angle (not produced) and the anteroventral margin of the carapace (serrated) agree with Jones’ description.

The integument is translucent in the present specimen, may be due to fixation in formalin.

The five free thoracic segments are well separated, almost as long as the carapace measured without the pseudorostrum. The middorsal spines at pereionites 4 and 5 and pleonite 1 are not discernable in the specimen from the Ifremer collection.

6, telson and uropods (left endopod in higher magnification); scale bars: 0.1 mm.

The pleon is 1.3 times longer than the carapace and the free thoracic segments combined. The last pleonite is 1.3 times as long as wide and 1.8 times longer than the telson.

The telson is shorter (0.6 times) than the uropod peduncle.

Antenna 1 ( Fig. 27 , A1): relative length of peduncle articles 1 to 3: 46/30/24

Maxilliped 2 ( Fig. 27 , Mxp2): B/R ratio 1.1, relative length of articles I to D: 0/15/44/26/15.

Maxilliped 3 ( Fig. 27 , Mxp3): B/R ratio 1.0, relative length of articles I to D: 7/18/34 /24/17.

Pereiopod 1 ( Fig. 27 , P1): B/R ratio 0.6, relative length of articles I to D: 0/ 12/50/23 /15.

Pereiopod 2 ( Fig.27 , P2): B/R ratio 0.7, relative length of articles I to D: 9/ 12/27/13 /39.

Pereiopod 3 ( Fig. 28 , P3): B/R ratio 1.5, relative length of articles I to D: 15/15/36/15/18.

Pereiopod 4 ( Fig. 28 , P4): B/R ratio 1.1, relative length of articles I to D: 15/23/ 35/15/12.

Pereiopod 5 ( Fig. 28 , P5): B/R ratio 0.6, relative length of articles I to D: 10/20/34 /19/17.

Uropod ( Fig. 28 , U): peduncle is as long as the last pleonite, half as long as rami;

The exopod bi-articulated, as long as endopod; endopod unarticulated, beset with numerous hair-like setae along inner margin, distal inner margin with three cuspidate setae and a strong terminal seta, endopod slightly curved as figured by Jones (1973).

Figures

FIGURE 26. Petalosarsia longirostris, non-ovigerous female; habitus, scale bar: 1 mm.

FIGURE 27. Petalosarsia longirostris, non-ovigerous female; A 1: antenna 1; Mxp 2: maxilliped 2; Mxp 3: maxilliped 3; P 1: pereiopod 1; P 2: pereiopod 2; scale bars: 0.1 mm.

FIGURE 28. Petalosarsia longirostris, non-ovigerous female; P 3: pereiopod 3; P 4: pereiopod 4; P 5: pereiopod 5; U: pleonite