A review of the families and genera of the superfamily PLATYSCELOIDEA Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), together with keys to the families, genera and species
Author
Zeidler, Wolfgang
text
Zootaxa
2016
4192
1
1
136
journal article
10.11646/zootaxa.4192.1.1
724e0dd4-6194-4e3a-bb22-e5259cb0a130
1175-5326
166420
B3AE1A8B-EE40-4ACF-879B-33B55FBD1FB8
Genus
Paratyphis
Claus, 1879
(
Figs 53–55
)
Paratyphis
Claus, 1879
: 4
(key), 13–14.—
Gerstaecker 1886
: 483
.—
Claus 1887
: 31
(key), 39.—
Stebbing 1888
: 1476
.—
Spandl 1927
: 227
(key), 243.—
Pirlot 1929
: 157
.—
Barnard 1940
: 541
(key).—
Hurley 1955
: 187
(key), 188.—
Bowman & Gruner 1973
: 55
(key), 55–56.—
Zeidler 1978
: 39
(key), 42.—
Vinogradov
et al
. 1982
: 439
(key), 448.—
Shih & Chen 1995
: 225
(key), 243.—
Vinogradov 1999
: 1200
(key), 1201.
Type species.
Paratyphis maculatus
Claus, 1879
by monotypy.
Type
material could not be found at the MFN or
ZMH
and is considered lost.
However
, the descriptions and figures of
Claus
(1879
,
1887
) readily distinguish this genus.
The
type
locality is the
South
Atlantic, off the
Cape
of Good Hope
.
Diagnosis.
Head round. Eyes occupying most of head surface; grouped in two fields on each side of head. Antennae 1 of males with 1-articulate peduncle; flagellum with large, crescent-shaped callynophore, with aesthetascs arranged in two-field brush medially, with three smaller articles inserted on antero-dorsal corner. Antennae 1 of females with 2-articulate peduncle; callynophore narrowly rectangular, with two smaller articles inserted terminally. Antennae 2 of males 5-articulate; strongly zig-zagged, with all articles folded back on each other, extending anteriorly under head and posteriorly between the gnathopoda and pereopoda to pereonite 4; basal article distinctly inflated, about half or less the length of following article; articles 2 & 3 sub-equal in length; terminal two articles of similar length, about half-length preceding one; terminal article pointing anteriorly. Antennae 2 of females 5-articulate, with very small terminal article. Mandibular incisor relatively broad, straight with several teeth, with small distal lobe medially; in male orientated more or less parallel to palp. Maxillae 1 consisting of elongate plates, with four bifid teeth distally on medial margin. Maxillae 2 consisting of slightly curved plates with distinctive, rounded, medial bulge, armed with fine setae terminally. Maxilliped with inner lobes completely fused; medial margin of outer lobes with membranous fringe. Coxae 1–6 separate from pereonites; coxa 7 mostly fused with pereonite. Gnathopods 1 & 2 simple. Pereopods 3 & 4 distinctly shorter than pereopods 5 & 6. Pereopod 5; basis very broad, oval-shaped, width about 0.4–0.5 x length; articles 3–7 inserted terminally, or sub-terminally to basis. Pereopod 6; basis very broad, relatively rectangular, with straight or slightly rounded distal margin, maximum width 0.4–0.5 x maximum length, with fissure; articles 3–7 inserted sub-terminally on basis; merus with antero-distal corner slightly extended, overlapping carpus medially. Pereopod 7 reduced in size with enlarged, elongate basis; with only 1–3 terminal articles. Uropods 1 & 2 with articulated exopoda and endopoda. Uropod 3; endopod fused with peduncle. Rami of all uropoda more or less lanceolate, usually with serrated margins. Gills all without folds.
Species.
Paratyphis maculatus
Claus, 1879
;
P. pa r v u s
Claus, 1887
;
P. promontorii
Stebbing, 1888
and
P. spinosus
Spandl, 1924
.
Sexual dimorphism.
The sexes are remarkably similar in general morphology, and except for the antennae and mandibles, there is no obvious sexual dimorphism, although in some species the basis of pereopod 7 is more elongate in females.
FIGURE 53.
Paratyphis promontorii
Stebbing, 1888
, male (5.3 mm), Tasman Sea, SAMA C5387.
A
, habitus. Scale bars = 0.5 mm (A), 0.2 mm (remainder).
FIGURE 54.
Paratyphis promontorii
Stebbing, 1888
, male (5.3 mm), Tasman Sea, SAMA C5387. Scale bar = 0.2 mm.
FIGURE 55.
Paratyphis promontorii
Stebbing, 1888
, female (4.1 mm) and male (5.3 mm), Tasman Sea, SAMA C5384 & C5387. Scale bars = 0.05 mm (Mx1 & 2), 0.2 mm (remainder).
Remarks.
This genus is characterised by the simple first gnathopoda, and the poorly developed chelae of the second gnathopoda. In this respect it resembles
Parascelus
and
Thyropus
, of the family
Parascelidae
, in which the gnathopoda are simple. However, in
Parascelus
the basis of pereopod 6 is without a fissure, and in
Thyropus
the fissure is located well above the telsonic groove.
Paratyphis
seems to be a relatively uncommon genus. Consequently very little is known about the biology of species, and there are no records of associations with gelatinous plankton. Although uncommon, it seems to be widespread in tropical and warm-temperate regions of the world’s oceans.
Species of
Paratyphis
are extremely difficult to determine with certainty and the genus is in need of revision. Good examples of the
type
species,
P. maculatus
, where not readily available for illustrative purposes, so
P. promontorii
was substituted here (
Figs 53–55
) because it is very similar to
P. maculatus
and may even prove to be synonymous.
Pirlot (1930)
and
Vinogradov
et al
. (1982)
recognise four species, for which the following key is provided.