Galathea patae, Osawa, 2006
|
publication ID |
https://doi.org/ 10.5281/zenodo.5402134 |
|
persistent identifier |
https://treatment.plazi.org/id/03E187A1-FFB3-FF94-FECC-9A543A23F941 |
|
treatment provided by |
Marcus |
|
scientific name |
Galathea patae |
| status |
sp. nov. |
Galathea patae View in CoL n. sp.
( Figs 1 View FIG ; 2 View FIG )
TYPE MATERIAL. — Japan. Off Naze, Amami-oshima Island, Ryukyu Islands, stn DY-03-08, 28°25.27’- 28°25.49’N, 129°28.39’- 129°28.30’E, 74-86 m, dredge, 18. VI.2003, coll. M. Osawa, holotype, ovig. ♀ cl 3.2 mm (NSMT-Cr 16114).
ETYMOLOGY. — The new species is named in honor of Dr Patsy A. McLaughlin, in recognition of her outstand-
ing contributions to the systematic study of crustaceans, especially hermit crabs.
DISTRIBUTION. — Known only from the type locality.
DESCRIPTION
Carapace ( Fig. 1A, B View FIG ), exclusive of rostrum and spines, 1.2 times as long as broad; dorsal surface with some breakable, feather setae; gastric, branchial, and cardiac regions with non-setiferous, interrupted transverse ridges; epigastric region with transverse row of four tubercle-like, very small spines; anterior branchial region also with few small tubercle-like spines medially; gastric region convex; branchial and cardiac regions elevated. Lateral margin slightly convex, with six spines: two in front of, and four behind cervical groove, first anterolateral and small, second minute, third shorter than fourth, fifth most prominent, sixth smaller than fifth; another spine ventral and somewhat posterior to anterolateral spine and dorsal to anterior end of linea anomurica. Cervical groove distinct. Frontal margin short, weakly oblique. Orbit produced but unarmed at lateral angle; infra-orbital margin with subtriangular process bearing few small denticles. Rostrum moderately narrow, triangular (apex broken), 0.4 length of remaining carapace, 1.5 times as long as broad when measured between proximal lateral incisions, nearly horizontal in lateral view; dorsal surface apparently naked, slightly concave medially; lateral margin with three shallowly incised teeth, proximal two teeth very small.
Pterygostomian flap ( Fig. 1B View FIG ) rugose but without spines on surface, anteriorly ending in minute spinule.
Third thoracic sternite ( Fig. 1C View FIG ) two times as broad as long; divided into two rounded lobes by median suture. Fourth thoracic sternite including lateral lobes 3.3 times longer than preceding sternite, 0.4 as long as broad, moderately narrowed anteriorly, grooved in anterior midline, with short transverse ridges bearing sparse short setae; anterolateral margin minutely tuberculate. Following sternites nearly smooth.
Abdominal segments ( Fig. 1A View FIG ) with some feather setae on dorsal surface; second to fourth segments with two uninterrupted, elevated transverse ridges, anterior ridge more prominent than posterior; sixth segment nearly transverse on posteromedian margin. Telson ( Fig. 1D View FIG ) well developed, relatively long, as long as broad, incompletely subdivided.
Ocular peduncles ( Fig. 1A, B, E View FIG ) subcylindrical, elongate, broadened proximally; mesial margin more strongly concave than lateral; surface with short protuberant ridges bearing sparse short setae; dorsal extension onto cornea rounded, with tuft of feather setae; cornea not dilated, 0.4 length of remaining peduncle.
Basal article of antennular peduncle ( Fig. 1A, E View FIG ) with well developed distodorsal and distolateral spines, distodorsal larger; distomesial spine very small; lateral margin with few small spines. Ultimate article with several short setae (not as tufts), on dorsodistal margin.
Antennal peduncle ( Fig. 1A, B, E View FIG ) short, barely reaching base of cornea. First article hardly visible from dorsal view, with distomesial spine barely reaching distal margin of second article. Second article with two small distal spines, distolateral spine terminating in proximal 0.3 length of third article and nearly paralleling lateral margin of third article, distomesial spine directed rather mesially. Third article with very small distomesial spine. Fourth article unarmed.
Third maxilliped ( Fig. 1F View FIG ) with ischium bearing small distal spines on each of flexor and extensor margins; mesial ridge with 15 denticles. Merus subequal in length to ischium measured in lateral midline, with four spines and few feather setae on flexor margin, proximal spine largest; extensor margin with subdistal protuberance, distal corner slightly produced but unarmed. Carpus with four protuberances on extensor margin. Propodus widened medially. Dactylus subovate. Exopod distinctly overreaching distal margin of merus.
Left first pereopod missing. Right first pereopod (broken in proximal part of palm) ( Fig. 2 View FIG A-C) three times as long as carapace including rostrum, slender, subcylindrical, with sparse feather setae on merus to palm and tufts of simple setae on fingers. Merus 1.8 times as long as carpus, with row of spines on each of dorsolateral, dorsomesial, ventrolateral, and ventromesial margins, distal spines prominent; lateral and mesial surfaces with few small spines. Carpus 0.9 length of palm, 3.6 times as long as distal breadth, with row of small spines on each of dorsolateral and dorsomesial margins; lateral and mesial surfaces with few small spines and short ridges. Palm 4.3 times longer than distal breadth, with some short, scale-like ridges and small spines. Fingers 0.7 length of palm, crossing distally; opposable margins slightly gaping, distally spooned; prehensile edge with row of small subtriangular teeth, proximal tooth larger; distal margin with three or four small teeth.
Second to fourth pereopods ( Fig. 2 View FIG D-G) moderately slender and long, decreasing in size posteriorly, second longest, with scattered feather setae on ischium, merus, carpus, and dorsal margin of propodus, and simple setae on dactylus, and ventral and distal margins of propodus. Meri slender on second but rather stout on third and fourth; lateral surface with few, weakly elevated scale-like ridges, bearing median spine near dorsal margin on fourth; dorsal margin with five or six (second), five (third), and four (fourth) spines; ventrolateral distal margin with spine on second and third but unarmed on fourth. Carpus with three (second and third) and one or two (fourth) spines on dorsal margin; lateral surface with two (second), three (third), and zero or one (fourth) spines subparalleling dorsal margin; ventrodistal margin with few obsolescent denticles. Propodus, exclusive of distal rounded projection, 1.3-1.5 times as long as dactylus, 4-4.3 times as long as high measured at base of distal projection; dorsal margin with two (second and fourth) and three or four (third) spines on proximal half; lateral surface unarmed; ventral margin with four or five slender corneous spines including distal paired spines. Dactylus gently curving, ending in strongly curved, sharp claw; ventral margin with four teeth diminishing in size proximally, each with slender corneous spine.
No epipods on pereopods.
Coloration
In freshly preserved: carapace, abdomen, ocular peduncles, and pereopods milky white, with scattered small red spots. Scattered feather setae on carapace, abdomen, ocular peduncle, and first pereopod red; plumose setae on second to fourth pereopods white.
REMARKS
The new species is assigned to the genus Galathea based on the following characters: carapace with transverse ridges on the entire surface; flattish, subtriangular but not dagger-shaped rostrum without a ventral carina; excavated orbit; third thoracic sternite with an anteromedian notch but not laterally widened; endopod of the uropod with a lateral margin being normal in position; second article of the antennal peduncle with distomesial and distolateral spines; and dactyli of second to fourth pereopods bearing proximally diminishing teeth on the flexor margin.
The elongate ocular peduncles and shapes of the telson and antennular basal article displayed by the new species are much like those of Fennerogalathea Baba, 1988 . However, Fennerogalathea is characterized by the carapace having scattered dorsal spines and no distinct set of transverse ridges, and the first article of the antennal peduncle being unarmed.The elongate ocular peduncles are also seen in Lauriea gardineri (Laurie, 1926) and L. siagiani Baba, 1994 (see Baba 1971, 1994; Osawa & Okuno 2004) and Galathea robusta Baba, 1990 (see Baba 1990, 2005). However, Lauriea is remote from Galathea , as noted by Baba (1971, 1988) and Baba & de Saint Laurent (1996).
Galathea patae n. sp. is unique among species of the genus in having non-setiferous transverse ridges on the carapace and relatively short merus of the third maxilliped. These characters separate this new species from all other congeners.
Although the rounded lateral orbital angle without a spine is one of the diagnostic characters of G. patae n. sp., this character is shared with G. bidens Baba, 1988 , G. multilineata Balss, 1913 , and G. pilosa de Man, 1888 (see Miyake & Baba 1966, 1967; Baba 1988). Galathea patae n. sp. has three small teeth on each lateral margin of the rostrum, whereas other known species of Galathea have four teeth, except for G. bidens (two distal teeth), G. lumaria Baba, 2005 (two long proximal spines and one small median spine), G. quinquespinosa ( Balss, 1913) (two long proximal spines), and G. multilineata and G. tropis Baba, 2005 (both, five teeth) (see Baba 1988, 2005).
| VI |
Mykotektet, National Veterinary Institute |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.