Platorchestiinae subfam. nov. (Amphipoda, Senticaudata, Talitridae) with the description of three new genera and four new species
Author
Lowry, J. K.
Author
Myers, A. A.
0000-0003-3256-2123
School of Biological, Earth and Environmental Sciences, University College Cork, Cork Enterprise Centre, Distillery Fields, North Mall, Cork, Ireland. bavayia @ gmail. com; https: // orcid. org / 0000 - 0003 - 3256 - 2123
bavayia@gmail.com
text
Zootaxa
2022
2022-02-17
5100
1
1
53
journal article
20608
10.11646/zootaxa.5100.1.1
cabdbbb1-1226-4c2e-b90b-fae0742b5091
1175-5326
6127681
F42DAC62-0E30-442E-A375-87FC02B2CC99
Tethorchestia
Bousfield, 1984
Tethorchestia
Bousfield, 1984: 204
.—
LeCroy, 2011: 743
, 759.—
Wildish & LeCroy, 2014: 557
, 558, key.—
Lowry & Myers, 2019: 84
, 87, figs 38, 39.
“
Tethorchestia
”.—
LeCroy, 2011: 743
, key, 757 diagnosis.
Type
species.
Tethorchestia antillensis
Bousfield, 1984
, original designation.
Included species.
Tethorchestia
contains 3 species:
T. antillensis
Bousfield, 1984
;
T. karukerae
Ciavatti, 1989
;
T. palaeorchestes
Bousfield & Poinar, 1995
(fossil, terrestrial, Oligocene).
Ecological
type
.
Beach-hoppers.
Habitat.
Living on semi-protected beaches sand beaches.
Diagnostic description (
male
).
Based on
Ciavatti (1989)
and
Wildish & LeCroy (2014)
.
Head.
Antenna 2
peduncular articles slender
.
Mandible
lacinia mobilis 4-cuspidate
.
Gnathopod 1
sexually dimorphic; subchelate; posterior margin of carpus and propodus each with lobe covered in palmate setae; propodus anterior margin with 4 groups of robust setae, ‘subtriangular’ with well-developed posterodistal lobe, palm transverse;
dactylus cuspidactylate
.
Gnathopod 2
subchelate; propodus palm acute; propodus palm evenly rounded; without palmar sinus; without proximal sinus; without large distal sinus; without proximal spine or thumb defining palm; without large projection near dactylar hinge; dactylus short, strongly curved, longer than palm; recurved distally, attenuated distally or slender, distally acute.
Pereopods 3–7
dactyli bicuspidactylate.
Pereopod 4
significantly shorter than pereopod 3; carpus significantly shorter than that of pereopod 3; dactylus amplidactylate,
thickened proximally with notch midway along posterior margin
.
Pereopod 6
shorter than pereopod 7, not incrassate; basis moderately expanded; male merus and carpus not expanded.
Pereopod 7
not incrassate; basis moderately expanded, or broadly expanded; posterior margin with distinct minute serrations, each with a small seta, posterodistal lobe present, shallow, broadly rounded; carpus unexpanded (subrectangular); subrectangular, or subtriangular (slightly); carpus subequal to propodus; propodus broad; length 3.3–6.5 × width; propodus with large distal tuft of setae.
Oostegites
(female) setae with simple smooth tips.
Pleon.
Pleopods 1–3
all well-developed, or all reduced (slightly).
Uropod 1
peduncle distolateral robust seta present; exopod without marginal robust setae;
endopod with marginal robust setae in 1 row
.
Uropod 2
exopod with marginal robust setae in 1 row; endopod with marginal robust setae in 2 rows.
Uropod 3
ramus shorter than peduncle.
Telson
completely cleft or apically incised, with 3–6 robust setae per lobe or with 7–9 robust setae per lobe.
Remarks.
Tethorchestia
is very similar to
Mexorchestia
.
Tethorchestia
has a posterodistal lobe on the basis of pereopod 7 (absent in
Mexorchestia
) and the oostegites have simple tips in
Tethorchestia
(oostegites with spatulate tips in
Mexorchestia
).
Distribution.
Mexico
and Caribbean Sea (
Bousfield 1984
,
Ciavatti 1989
).