Galeatylinae, a new subfamily of Atylidae for Galeatylus coripes, new genus and species, from the Bass Strait, south-eastern Australia (Amphipoda Dexaminoidea)
Author
Just, Jean
text
Zootaxa
2019
2019-11-28
4701
3
291
295
journal article
24779
10.11646/zootaxa.4701.3.5
3652d8e1-9c0c-40db-9efa-2ff2661c3437
1175-5326
3558055
ECE03633-DD34-425F-A02D-09F483A54A6A
Galeatylus coripes
sp. nov.
Figures 1–3
Type fixation.
Holotype
,
♂
, here designated.
Etymology
. The epithet consist of the Latin
cor
(heart) and
pes
(foot) denoting the shape of the propodus of pereopods 3 and 4.
Material examined.
Holotype
,
♂
,
3.3 mm
.
Australia
,
Bass Strait
,
94 km
N of North Point
,
Flinders Island
, 38˚53.42’S 147˚55.06’E,
71 m
, medium sand,
R. Wilson
,
17 November 1981
,
RV
Tangaroa
, stn BSS 171,
NMV
J62381
(unique).
Description.
Rostrum
massive, angularly truncate, overhanging half the length of antenna 1 article 1.
Lateral head margin
with 2 rectangular sharply pointed projections, with strong concavities above, between and below projections.
Eyes
oval, situated level with upper projection.
FIGURE 2.
Galeatylus coripes
gen. et sp. nov.
, holotype.
ll
, lower lip;
md
, mandible (
l
, left,
r
, right);
mx1 and mx2
, maxilla 1 and 2;
mxp
, maxilliped;
ul
, upper lip.
Antenna 1
short, about as long as pereonites 1–5 combined, peduncle article 1 as long as 2 and 3 combined, 3 half length of 2; article 1 with mid-dorsal projection carrying a few small pappose setae, accessory flagellum absent; flagellum as long as peduncle articles 2 and 3 and half of 1, with 6 articles.
Antenna 2
about as long as pereonites 1–6 and half of 7 combined, article 5 nearly as long as 1–4 combined; flagellum of 6 articles, as long as peduncle article 5.
Mouthparts
.
Upper lip
rounded triangular, broader than long, apex with tiny setules.
Mandible
molar rather cylindrical (left) and elongate pointed (right); palp of 3 articles, article 2 with a couple of small setae, article 3 with apical tuft of 1 long and 4 short setae.
Lower lip
main lobes broadly rounded, distally with small sharp setae and tiny setules; inner lobes broadly rounded with tiny setules apically.
Maxilla 1
palp of 2 articles, article 2 much longer than 1 and overreaching outer lobe with about 1/4 its length, apex with 5 pointed robust setae; outer plate with oblique terminal row of 7 serrated spine-setae; inner plate short, distally tapering, with 2 apical plumose setae.
Maxilla 2
outer plate distally rounded with dense row of setae; inner plate nearly as long as outer, more slender, apex with bunch of setae and single long plumose mediodistal seta.
Maxilliped
palp of 4 articles; outer plate reaching apex of palp article 2, with medial and apical row of spatulate setae; inner plate reaching half way along outer plate with 3 spatulate setae and a few simple setae on apical margin.
FIGURE 3.
Galeatylus coripes
gen. et sp. nov.
, holotype.
gp1 and gp2
, gnathopods 1 and 2;
p3
, pereopod 3;
p5–p7
, pereopods 5–7.
Pereonites
1–7 and
pleonites
1–3 dorsally smooth; e
pimeral plate
1 broadly rounded distally, plate 2 with angular posterodistal corner, plate 3 rounded posteriorly.
Coxal plates
1–4 simple, about as long as broad, distally rounded except plate 4 with nearly straight distal margin and acute posterodistal corner; plates 5 and 6 with tiny anterior lobe and large tapering posterior lobe; plate 7 broadest posteriorly.
Gnathopods
1 and 2 short;
gnathopod 1
carpus and propodus of subequal length and width, cutting edge of propodus defined by 2 robust setae, posterior margin with an additional robust seta more proximal, cutting edge otherwise with several small simple setae;
gnathopod 2
carpus about 1/5 longer than propodus, propodus cutting edge defined by 2 robust setae.
Pereopods 3 and 4
similar, nearly naked basis as long as ischium, merus and carpus combined, merus twice as long as carpus and propodus combined, carpus short, 1/5 length of merus, ring-shaped, about twice as broad as long, propodus inserted into carpus on a narrow stub with rest of article forming heart-shaped distally tapering segment, dactylus short, as long as broad, conical, unguis tiny, curved.
Pereopods 5–7
similar except basis of pereopod 5 with rounded posteroproximal lobe and posterodistal acute blunt lobe, concave in between lobes; basis of pereopod 6 with larger rounded posteroproximal lobe, distal half of article tapering to ischium; basis of pereopod 7 posterior margin projecting in an broad, even, slightly scalloped curve with small setae in indentations, without posterodistal projection; merus of all 3 pereopods about as long as carpus and propodus combined, propodus length about 2/3 of carpus, joining carpus in ordinary fashion not heart-shaped, dactylus very short and broad, with small curved unguis.
Penile papilla
short, rounded.
Uropods
1–3 reaching back to almost the same point, with uropod 2 outer ramus slightly shorter, all rami with a few terminal robust setal;
uropod 1
rami about 2/3 length of peduncle, with dorsal rows of robust setae;
uropod 2
outer ramus 2/3 length of peduncle, inner ramus 3/4 length of peduncle both rami with short row of robust setae;
uropod 3
peduncle about 1/3 length of outer ramus, rami of subequal length with few tiny setae, and a single dorsolateral robust setae on outer ramus.
Telson
reaching to nearly half way along uropod 3 outer ramus, as long as broad, split slightly more than half length, each lobe with 2 doublets of small setae, 3 of them pappose, apices without robust setae.