Oxynaspididae (Crustacea, Cirripedia): phylogenetics and evolutionary ecology, with descriptions of three new genera and six new species
Author
Van, Robert J.
Author
Dekelboum, Allen M.
text
Zootaxa
2011
3103
1
32
journal article
45961
10.5281/zenodo.279183
fa2365c5-dad4-43a7-906c-5409b8d00e2c
1175-5326
279183
Minyaspis amylaneae
sp. nov.
Figures 9
,
10
Material examined.
Holotype
:
CASIZ
110160
, 1 complete, intact specimen, attached to
Cirrhipathes anguina
Dana
(
CASIZ
113593);
Fiji
Is, Great Astrolabe Reef, NE of Dravuni I.,
18° 44.08’ S
,
178° 32.63’ E
; depth:
14 m
;
18 June 1998
; coll. Robert Van Syoc (RVS-439).
Paratypes
:
CASIZ
110132
,
1
specimen, mouthparts and cirri on microslide; same locality as
holotype
.
CASIZ
113621,
1
specimen, plates on SEM stub, no body;
Fiji
Is., N Astrolabe Reef, S end;
18° 40.54’ S
,
178° 31.34’ E
; depth:
14 m
;
20 June 1998
; coll. Robert Van Syoc (RVS-444).
CASIZ
110132
,
1
specimen, mouthparts and cirri on glass microscope slide; same locality as
holotype
.
CASIZ
110133
,
1
specimen; same locality as
holotype
.
CASIZ
110167
,
1
specimen; same locality as
holotype
.
CASIZ
110136
,
1
specimen;
Fiji
Is, N Astrolabe Reef, SW side, outer reef, sheer wall with shallow caves;
18° 40.17’ S
,
178° 31.04’ E
;
24–27 m
;
13 June 1998
; coll. Robert Van Syoc (RVS-426).
CASIZ
113617,
1
specimen;
Fiji
Is, N Astrolabe Reef, SW side, outer reef, sheer wall with shallow caves;
18° 40.17’ S
,
178° 31.04’ E
;
24–27 m
;
13 June 1998
; coll. Robert Van Syoc (RVS-426).
CASIZ
113618,
1
specimen;
Fiji
Is, N Astrolabe Reef, SW side, outer reef, sheer wall with shallow caves;
18° 40.17’ S
,
178° 31.04’ E
;
24–27 m
;
13 June 1998
; coll. Robert Van Syoc (RVS-426).
CASIZ
113615,
3
specimens;
Fiji
Is, N Astrolabe Reef, SW side, outer reef, sheer wall with shallow caves;
18° 40.17’ S
,
178° 31.04’ E
;
24–27 m
;
13 June 1998
; coll. Robert Van Syoc (RVS-426);.
CASIZ
113616,
2
specimen;
Fiji
Is, N Astrolabe Reef, SW side, outer reef, sheer wall with shallow caves;
18° 40.17’ S
,
178° 31.04’ E
;
24–27 m
;
13 June 1998
; coll. Robert Van Syoc (RVS-426).
CASIZ
113619,
2
specimens;
Fiji
Is, Great Astrolabe Reef, SE corner of outer reef;
18° 41.47’ S
,
178° 31.24’ E
; depth:
21 m
;
22 June 1998
; coll. Robert Van Syoc (RVS-448).
CASIZ
113620,
21
specimens,
Fiji
Is, N Astrolabe Reef, S end;
18° 40.54’ S
,
178° 31.34’ E
; depth:
14 m
;
20 June 1998
; coll. Robert Van Syoc (RVS-444); SIO-BIC C11215, from
CASIZ
113620.
Diagnosis.
Single filamentary appendages on either side at base of cirrus I; caudal appendages absent; tergum and scutum without toothed or jagged margins; carina forming angle greater than 90° at umbo, basal end with shallow fork (
Fig. 9
).
Description.
Capitulum with large non-calcified area between scutum and carina (
Fig. 10
A); capitular height less than twice its width; low growth ridges on all plates; scuta and terga with opaque white markings approximate to adductor muscle attachment sites; covered with chitinous, golden-brown epicuticle.
Scutum (
Fig. 9
E,F;
Fig. 10
A) irregularly shaped, not quadrangular; umbo subcentral, not on occludent margin; separated from carina by wide non-calcified area except near basal margin of carina; near tergum at slightly less than one-half length of tergum; occludent and basal margins forming an angle less than 90°; basal margin with well-defined concavity; occludent margin coincident with mantle margin; occludent edge smooth, broadly concave in upper half; carinal margin shallowly concave; adductor muscle pit shallow.
Tergum (
Fig. 9
C,D;
Fig. 10
A) broadly triangular; margins nearly touching carina and scutum; umbo below apex; scutal margin smooth; occludent edge broadly convex.
FIGURE 9.
Minyaspis amylaneae
sp. nov.
Paratype, CASIZ 113621. Carina, dorsal view (A), side view (B). Tergum exterior (C), interior (D). Scutum exterior (E), interior (F). Scale bar equals 1.5 mm for A, B, C, D; 1 mm for E and F.
FIGURE 10.
Minyaspis amylaneae
sp. nov.
Paratype CASIZ 110136; outline of whole specimen showing general arrangement of plates in relation to each other (A), plate details are not shown in this simple outline drawing, see SEMs in Fig. 9 for plate details. Paratype CASIZ 110132; Mandible (B), Maxilla 1 (C), Cirrus I (D). Holotype CASIZ 110160; whole specimen, with host tissues covering capitulum except where abraded away from handling (E).
Carina (
Fig. 9
A,B;
Fig. 10
A) straight in upper portion, line from apex to umbo passing only through carina, similarly line from apex to basal/peduncular margin passing through scutum; umbo between basal one-fifth and one-third; basal margin deeply forked, extending less than halfway across peduncle; longer than scutum; width narrowest at umbo; extending up about one-half length of tergum; lacking shallow inflection between basal margin and umbo.
Labrum bullate.
Mandible (
Fig. 10
B) with 4 teeth and rounded fifth subtooth at cutting edge inferior margin, first tooth largest, second about half length of first, third and fourth slightly shorter; face of mandible and superior and inferior margins setose.
First maxilla (
Fig. 10
C) with deep notch in superior half of cutting edge; 2 large, long spines above notch, many slightly shorter spines below notch; setae in notch, on face of maxilla and along superior and inferior margins.
Cirrus I (
Fig. 10
D) with anterior ramus shorter than posterior; other cirri with rami about equal. Setae simple. Cirral counts are as follows:
CI CII CIII CIV CV CIV Ant. 6
12 16 14
16 17 Post.
10 12 16
14 15 17
Ant.
7 16 17
17 17 15 Post. 14 17 17 15 16 16 Caudal appendages absent. Single filamentary appendages absent at base of Cirrus I. Dorsal filamentary appendages lacking.
Etymology.
Named in honor of Amy Lane Palenscar Van Syoc, who assisted in collecting specimens on the CAS Dravuni Astrolabe Reef Expedition of
June 1998
.
Remarks.
Although they are somewhat similar in outward appearance, the terga of
M. reducens
(
Foster, 1982
)
have prominently toothed edges while those of
M. amylaneae
sp. nov.
have smooth edges.
Minyaspis amylaneae
falls between the
M. granti
(
Totton, 1940
/
M. bocki
(
Nilsson-Cantell, 1921
) and the
M. michi
(
Zevina, 1983
/
M. sinensis
(
Ren, 1983
)
branches in the phylogenetic tree herein based on morphological characters (
Fig. 15
). It can be distinguished from these closest species by the proximity of the basal margins of the scutum and carina in
M. amylaneae
. These two plates are not close to each other in any of the other four species.
Minyaspis amylaneae
also has the carinal umbo above the basal one-fifth and below the basal one-third of the carina, whereas in
M. granti
and
M. bocki
the umbo is located in the basal one-fifth of the carina and in
M. michi
and
M. sinensis
it is located above the basal one-third of the plate.