with description of three new species
Author
Bamber, Roger N.
text
Zootaxa
2004
458
1
12
journal article
10.5281/zenodo.157995
b9166728-a5d6-4559-99ea-e18ee638f2ab
11755326
157995
Pycnogonum cranaobyrsa
sp. nov.
Material
:
1 female
,
holotype
(NHM.2004.47), CP214, East Coast of
Taiwan
, N/
O
'Fishery Researcher 1'
TAIWAN
2003,
24º28.59'N
122º12.66'E
to
24º25.66'N
122º12.78'E
,
490 to 1027 m
;
27/08/2003
, coll. TY Chan.
Description
: relatively large
Pycnogonum
, trunk length (anterior of cephalon to posterior of fourth lateral processes)
4.5 mm
, leg span approximately
20 mm
. Integument surface densely ornamented with small wartlike papillae, each papilla with minute tubercles or occasional setae over surface (
Fig. 4
B); pale strawcoloured in life grading to pale grey on tarsi. Trunk (
Figure 4
A, C) fully segmented, tapering from anterior to posterior, lateral processes short. Dorsal trunkmidline tubercles present: tall pointed tubercles mounted on raised posterior rim of first to third trunk segments; smaller, rounded tubercles on anterior of fourth trunk segment, and centrally on cephalon. Cephalon hexagonal, 40% of trunk length, domed ocular tubercle about 1.5 times as high as wide, bearing four eyes coloured red in life; second and third trunk segments each half as long as cephalon, second 0.77 times as wide as trunk length; fourth trunk segment slightly longer than third; dorsodistal tubercles present on all lateral processes, additional posterodistal lateral process tubercles present on first and second trunk segments. Abdomen truncate, naked, not articulating, held horizontal, wider distally, reaching back as far as distal edge of coxa 2 of fourth legs.
Proboscis naked, strongly tapering, without tubercles or papillae, 1.3 times as long as cephalon; oral glands (
sensu
Staples 2002
) not seen. Oviger absent.
FIGURE 4
.
Pycnogonum cranaobyrsa
sp. nov.
, female holotype, A, body, dorsal; B, profile of trunk papilla; C, body, lateral outline, integumental papillae not shown; D, third left leg. Scale line = 2 mm for A, C and D.
Third leg (
Figure 4
D) mainly without conspicuous swellings or tubercles. Coxae subequal, wider than long; femur longest article, 2.25 times as long as wide, with midventral swelling bearing short spine; tibia 1 0.85 times as long as femur, twice as long as wide, with one midventral spine; tibia 2 0.85 times as long as tibia 1, without spines but with ventrodistal tuft of fine setae; tarsus short, quadrangular, with fine ventral setae; propodus slender, curved, with ventral fine setae mainly in a single row, and occasional small lateral spines; main claw 0.4 times length of propodus; auxiliary claws absent. Ventral setae on tibia 2, tarsus and propodus not bifurcate.
Female gonopore conspicuous on posterodorsal surface of coxa 2 of fourth legs (arrowed on
Fig. 4
A). Coxal glands (
sensu
Staples 2002
) not seen.
Measurements (mm)
: trunk length 4.51; width across second lateral processes 3.49; proboscis length 2.42; abdomen length 1.52; third leg, coxa 1 0.68, coxa 2 0.78, coxa 3 0.68, femur 2.03, tibia 1 1.75, tibia 2 1.46, tarsus 0.23, propodus 1.38, claw 0.26.
Etymology
: from the Greek
kranaos
—rugged, rocky, and
byrsa
—hide or skin, referring to the complex pustulation of the integument of the present species (female, noun in apposition).
Remarks
: There is a number of
Pycnogonum
species with a slender tapering proboscis, no auxiliary claws and pointed middorsal trunk tubercles, but only the present species has the pustulate integument together with a rounded ocular tubercle. Using the key to the genus of
Stock (1966)
,
P. cranaobyrsa
identifies to couplet 20, where both
P. t o r re s i
Clark, 1963 and
P. indicum
Sundara Raj, 1930
are distinct from the present species in having a distally rounded abdomen and blunt (distally rounded) trunk tubercles.
P. i n d i c u m
is further distinguished owing to its compact leg articles, both femur and tibia 1 being less than twice as long as wide (
Sundara Raj 1930
).
P. cranaobyrsa
bears more similarity to
P. o c c a
Loman
, 1908, but the latter species has a distally pointed ocular tubercle and more slender leg articles (
Staples 2002
). Of other similar species described since Stock's (1966) review of the genus,
P. eltanin
Fry & Hedgpeth, 1969
is different from the present species in having distally rounded trunk tubercles;
P. (N) moniliferum
Stock, 1991
does have distally pointed trunk tubercles (see Bamber in press), but differs from
P. cranaobyrsa
in having a distally pointed ocular tubercle, a dorsal tubercle on coxa 3, and numerous spines and setae on the leg articles.