Saltipedis (Spinosaltipedis) puertoricensis, a new subgenus and species of apseudomorphan (Crustacea: Tanaidacea: Parapseudidae) from coastal waters off Culebra Island, Puerto Rico, with keys and taxonomic observations
Author
Morales-Núñez, Andrés G.
Author
Heard, Richard W.
Author
Alfaro, Mónica
text
Zootaxa
2010
2578
25
46
journal article
10.5281/zenodo.197554
801471fc-77ab-42d0-97ac-8d9dfe7925dc
1175-5326
197554
Subgenus
Saltipedis (Spinosaltipedis)
, new subgenus
Diagnosis:
Parapseudidae
,
Parapseudini
,
Saltipedis
sensu
lato
. Epistomal spine appearing absent. Surface of mandible between base of palp and molar process with six to seven distinctive, well-developed, buttressed, naked setae (
Fig. 3
E). Epignath with seta on inner subdistal margin minute (vestigial); length less than 1/8 width of epignath (
Fig. 4
E).
Type
species:
Saltipedis puertoricensis
,
n. sp.
Etymology:
From the Greek word
Spino
= referring to spines on mandible +
Saltipedis
Remarks:
The
Spinosaltipedis
,
n
.
subgen
.
, is characterized by a combination of the presence of unique and distinctive accessory spiniform setae on the mandible and the lack of an epistomal spine. The lack of an epistomal spine falls within
Saltipedis
sensu
lato
since it is also apparently absent on
S.
(
S.
)
achondroplasia
(R. Bamber, per. com.
July 2009
). The setation of basal article of the uropod and pleotelson (
Fig. 2
D) may represent additional characters, but this cannot be confirmed until reexamination of the species within the subgenus
Saltipedis
.
Pending the results of future morphological and molecular systematic/phylogenetic studies for the taxa within the family
Parapseudidae
and related groups, we tentatively place the new Puerto Rican subgenus within the genus
Saltipedis
sensu
lato.
Though readily distinguished from the other species within the genus, the subgeneric status of
S. tetracanthus
Guţu and Angsupanich, 2004
remains unsettled, pending the a detailed description of its mouth parts and maxilliped.
The generic status of the
Longipedis
erected by Larsen and Shimomura (2006) is problematic. Like other members of the similar genus
Podictenius
Guţu, 2006
, it apparently lacks a dorsal transverse row of setae on the dorsum of the first abdominal segment, which we tentatively consider a pivotal unifying character for the genus
Saltipedis
. For this reason, we resurrect the monotypic genus
Longipedis
for which
L. fragilis
was originally designated as the
type
species.
In some parapseudid taxa, however, the presence of a dorsotransverse row of setae on the first abdominal segment may be variable. For example, in genus
Parapseudes
it is present in
P. latifrons sensu
Lang 1966
and
P. arenamans
Larsen and Shimomura, 2008
, but is lacking or dorsally incomplete on
P. a l g i c o l a
(Shiino, 1952);
P. neglectus
Miller, 1940
(R.
Heard
, per. obser.) and
P. pedispinis
(Boone, 1923)
(see
Menzies 1953
), and apparently
P. trispinosus
Guţu, 1998
(see
Guţu 1998
).
The occurrence of mandibular accessory setae and a dorsotransverse row of setae on the first abdominal segment distinguish
Spinosaltipedis
from the otherwise similar western Atlantic members of
Podictenius
Guţu, 2006
. Like
Spinosaltipedis
,
two of three nominal species of
Podictenius
,
P. e s p i n o s u s
(Moore, 1901) and
P. tomiliffei
Guţu, 2006
, are known only from the tropical waters of the western Atlantic. The third species,
P. estafricanus
Guţu, 2006
, which appears quite different from its two Atlantic congeners, is known from the western Indian Ocean (
Guţu 2006
).
Guţu (2006)
considered the presence of prominent row of spiniform setae along the anteroproximal margin of the basis for the first pereopod an important generic character. Although the first pereopod of
Spinosaltipedis
has a few such setae, they are smaller and less distinctive than the illustration of Moore (1901: Plate 7, fig. 4). Also,
Spinosaltipedis
is differentiated from
Podictenius
by having the first pereopod bearing short, blunt conical spiniform setae (instead of acute, elongate spiniform setae) on the margins of the carpus and propodus; however, species with both these setal conditions on the first pereopod occur within the subgenus
Saltipedis
(see
Figure 7
).
Based on the current state of knowledge and complexity of apsudomorphan taxonomy, we believe that many of the supraspecific taxonomic designations (e.g., genera, subfamilies, and families) maybe based upon, or at least in part upon, convergent or independently derived characters. For these reasons the taxa within the suborder should be the subjects of future systematic revisions.