A review of the hyperiidean amphipod superfamily Archaeoscinoidea Vinogradov, Volkov & Semenova, 1982 (Crustacea: Amphipoda: Hyperiidea)
Author
Zeidler, Wolfgang
text
Zootaxa
2006
1125
1
37
journal article
50750
10.5281/zenodo.171814
dbe36ce3-4931-43da-a461-f1ebf3e71951
11755326
171814
Family
ARCHAEOSCINIDAE
Barnard, 1930
Diagnosis
Body length less than 10.0 mm, with extreme sexual dimorphism in body shape. Females with spherically inflated pereon because of enlarged pereonites 1–5, slightly longer than deep, more than twice as long as pleon and urosome combined; head immersed in first pereonite; pereonites 6 & 7 and pleon slender. Males with slender pereon (sciniform), equal in length to, or slightly shorter than, pleon and urosome combined; head as long as first pereonite. Pereonites all separate. Coxae separate from pereonites. Antennae 1 of females as long as head and first pereonite combined; of males as long as head and first 1.5–3 pereonites combined; peduncle 3articulate in females, 2articulate in males. Antennae 2; length 0.5–0.7x A1. Mandibles with slender palp, length of third article 1.2–2.0x length of first two combined; incisor very narrow; left mandible with lacinia mobilis. Maxillae 1 with slender palp, comparatively narrow outer lobe and short inner lobe. Maxillae 2 with relatively slender lobes, the inner slightly shorter than the outer one. Maxilliped with oval, unarmed outer lobes; inner lobes about 0.2–0.8x length of outer, fused proximally, separate distally. Gnathopods 1 & 2 simple; carpus not especially broadened distally; dactylus inserted subterminally in G1, sometimes also in G2. Pereopods 3–7 simple. Pereopods 5–7 without (
Archaeosina
) or with retractile dactyls which may be hooded (
Paralanceola
). Urosomite 2–3 with partial suture ventrally. Uropods slender, with articulated exopods and endopods. Telson shorter than peduncle of U3, triangular with rounded or pointed apex. Gills on pereonites 3–6. Oostegites on pereonites 2–5.
Two genera:
Archaeoscina
and
Paralanceola
.
Remarks
In the above diagnosis, reference to female characters is restricted to
Archaeoscina
because females of
Paralanceola
are not known.
Woltereck (1909)
attempted to rationalise the systematics of some of the families and genera now included in the infraorder Physosomata and provisionally included the genera
Archaeoscina
Stebbing, 1904
,
Micromimonectes
Woltereck, 1906
,
Mimonecteola
Woltereck, 1909
and
Microphasma
Woltereck,
1909
in the family Pygmaeidae. However, because this group did not include the genus
Pygmaeus
, from which the family name could be derived,
Barnard (1930)
proposed the family name
Archaeoscinidae
to accommodate this group of genera, derived from the oldest available generic name in the group,
Archaeoscina
.
Stephensen and Pirlot (1931)
, in a study of this group and related genera, proposed the family
Microphasmidae
for
Microphasma
and noted that
Archaeoscina
was only known from males and
Micromimonectes
only from adult females. Subsequently,
Pirlot (1939)
, followed by
Vinogradov (1956)
, synonymised
Micromimonectes
with
Archaeoscina
, and when
Vinogradov (1957)
also removed
Mimonecteola
to the family
Microphasmidae
, the family
Archaeoscinidae
consisted of only one genus,
Archaeoscina
.
Paralanceola
Barnard, 1930
is known only by the unique
type
of
P. anomala
, which Barnard tentatively placed in the family
Lanceolidae
, based on the hooded, retractile dactyls of pereopods 5–7. However, this character is not unique to this family and is also found in the
Chuneolidae
,
Proscinidae (
Mimoscina
)
and
Scinidae (
Ctenoscina
)
.
Pirlot (1939)
suggested that
Paralanceola
might belong with
Archaeoscina
and
Vinogradov
et al
. (1982)
finally concluded that this genus is best placed in the family
Archaeoscinidae
, based on the structure of the mouthparts, particularly the narrow mandibular incisor, mandibular palp and also the morphology of the antennae. This is supported by the present study which includes a reexamination of the remains of the unique
type
of
P. anomala
and five additional specimens attributed to this genus.
In all specimens of this family, that I have examined, I found a partial suture between urosomites 2 and 3, but only ventrally. It is present in all other members of the Physosomata examined and I have also found it in the family
Vibiliidae
. This character has not been recorded for the Physosomata previously and may be a remnant of a primitive lineage to the Gammaridea.