Sea spiders (Arthropoda: Pycnogonida) collected during the Madibenthos Expedition from Martinique shallow waters
Author
Sabroux, Romain
F48B4ABE-06BD-41B1-B856-A12BE97F9653
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle CNRS, Sorbonne Université, EPHE, UA. 57 rue Cuvier, CP 51, 75005 Paris, France.
pycnogonides@gmail.com
Author
Hassanin, Alexandre
6CAA213C-384A-4111-8F70-1E8E07D3347D
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle CNRS, Sorbonne Université, EPHE, UA. 57 rue Cuvier, CP 51, 75005 Paris, France.
alexandre.hassanin@mnhn.fr
Author
Corbari, Laure
9E5EBA7B-C2F2-4F30-9FD5-1A0E49924F13
Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle CNRS, Sorbonne Université, EPHE, UA. 57 rue Cuvier, CP 51, 75005 Paris, France.
corbari@mnhn.fr
text
European Journal of Taxonomy
2022
2022-12-12
851
1
1
141
http://dx.doi.org/10.5852/ejt.2022.851.1999
journal article
221137
10.5852/ejt.2022.851.1999
c70e23de-1f95-46fb-899b-9754b6145d52
2118-9773
7428095
7317EA8C-7C05-4E24-A38C-30F860013694
Anoplodactylus micros
Bourdillon, 1955
Figs 20
,
24
Anoplodactylus micros
Bourdillon, 1955: 591–592
, pl. 1 fig. 3–8.
Anoplodactylus micros
–
Stock 1986
: tab. 1. —
Montoya Bravo
et al.
2009: 22–24
. —
Müller & Krapp 2009: 10
, 86 (key), 103–105, 137 (list), tab. 1, fig. 55. —
Lucena
et al.
2015
: tab. 1. —
Sabroux
et al.
2019b
(pro parte): tab. 1, figs 3, 5.
Material examined
Neotype
MARTINIQUE
•
♂
;
Les
Anses-d’Arlet;
14°29.7ʹ N
,
61°05.4ʹ W
; depth
19 m
;
7 Sep. 2016
; st. AB155; MNHN-IU-2016-1325/
MK411100
.
Other material
MARTINIQUE •
1 ♀
, 3 juvs; same collection data as for neotype; MNHN-IU-2016-1230
•
1 ♀
; same collection data as for neotype; MNHN-IU-2016-1387/
MK411110
•
1 ♀
; same collection data as for neotype; MNHN-IU-2016-1388
•
1 ♂
;
Anse Noire
;
14°32ʹ N
,
61°05.3ʹ W
; depth
13 m
;
6 Sep. 2016
; st. AB150; MNHN-IU-2016-802/
MK411125
•
1 ♂
;
Grande Anse d’Arlets
;
14°30.5ʹ N
,
61°06.1ʹ W
; depth
20–23 m
;
6 Sep. 2016
; st. AB152; MNHN-IU-2016-803
•
1 preadult
♀
;
Pointe du Vauclin
;
14°33.6ʹ N
,
60°49.7ʹ W
; depth
2 m
;
12 Sep. 2016
; st. AD230; MNHN-IU-2016-804/
MK411126
•
1 ♂
; same collection data as for preceding; MNHN-IU-2016-568
•
1 ♀
;
Grande Anse d’Arlets
;
14°29.9ʹ N
,
61°05.4ʹ W
; depth
28 m
;
7 Sep. 2016
; st. AB157; MNHN-IU-2016-536
•
1 ♂
,
1 ♂
ov.;
Baie de St-Pierre
;
14°45.1ʹ N
,
61°11ʹ W
; depth
17 m
;
4 Oct. 2016
; st. AB388; MNHN-IU-2016-1059
•
1 ♂
; same collection data as for preceding; MNHN-IU-2016-1386
•
1 ♂
;
Grande Anse du Diamant
;
14°28ʹ N
,
61°00.1ʹ W
; depth
12 m
;
26 Sep. 2016
; st. AB360; MNHN-IU-2016-1080
•
1 ♂
; same collection data as for preceding; MNHN-IU-2016-1218
•
1 ♂
;
Le Prêcheur
;
14°49.1ʹ N
,
61°13.8ʹ W
; depth
20–25 m
;
8 Oct. 2016
; st.
AS
576; MNHN-IU-2016-1087
•
1 ♂
,
1 ♀
;
Presqu’Île de la Caravelle
;
14°48.4ʹ N
,
60°52.8ʹ W
; depth
23–25 m
;
20 Sep. 2016
; st. AB197; MNHN-IU-2016-1139
•
1 ♂
; same collection data as for preceding; MNHN-IU-2016-1250
•
1 preadult
♂
; same collection data as for preceding; MNHN-IU-2016-1391
•
1 ♀
;
Grande Anse du Diamant
;
14°27.9ʹ N
,
61°01.4ʹ W
; depth
17 m
;
26 Sep. 2016
; st. AB358;
MNHN-
IU-2016-1211
•
1 ♀
,
1 juv.
;
Anse des Galets
;
14°51.4ʹ N
,
61°12.8ʹ W
; depth
10 m
;
7 Oct. 2016
; st. AB567; MNHN-IU-2016-1246
•
2 ♀♀
,
4 ♀♀
gr.;
Pointe de la Baleine
;
14°31.1ʹ N
,
61°05.9ʹ W
; depth
17–19 m
;
30 Sep. 2016
; st. AB369; MNHN-IU-2016-1258
•
1 ♀
;
Anse Couleuvre
;
14°50.4ʹ N
,
61°13.4ʹ W
; depth
7 m
;
1 Oct. 2016
; st. AB463; MNHN-IU-2019-3390
.
Description
(
neotype
,
♂
, MNHN-IU-2016-1325)
BODY.Small-sized species; trunk segmentation incomplete with 3
rd
and 4
th
segments fused; cuticle smooth. No dorsomedian ornamentation. Ocular tubercle less than twice as tall as wide, distal tip triangular, with two pointy lateral sense organs above four large pigmented eyeseyes. Two setae laterally positioned on ocular tubercle between anterior and posterior eyes. Post-ocular neck medium-sized. Lateral processes about as long as wide, well separated by less than their own diameter, 3
rd
and 4
th
the closest. Lateral processes ornamented with a rounded tubercle, bearing one seta.
PROBOScIS. Cylindrical, with setae on ventral surface, constricted medially and distally.
ABDOMEN. Medium-sized, diagonally oriented, reaching beyond lateral processes of 4
th
trunk segment.
CHELIFORE. 2-articled, reaching beyond mouth. Scape 1-articled, about 4 times as long as wide, carrying setae distally. Chela carrying setae, fingers slightly longer than palm. Fingers subequal, crossing at tip, with few teeth.
PALP. Absent.
OvIGER. 6-articled, with scarce setae. 1
st
article about 1.5 times as long as wide. 2
nd
article about ¼ longer than 1
st
article, slenderer. 3
rd
article longest, 1.5 times as long as 1
st
, with constriction at base. 4
th
and 5
th
articles about half as long as 3
rd
, 5
th
most setose. 6
th
article smallest, bud-like, with distal seta.
LEGS. Stout. Coxa 1 slightly longer than wide, carrying setae at distal margin. Coxa 2 about ⅔ longer than coxa 1 or 3, with small ventrodistal spur on 3
rd
and 4
th
legs. Femur longest, more than 3 times as long as median width, with one long dorsal seta on distal margin, and one short cement gland tube, about mid-sized and slightly constricted at base. Tibia 1 about ¾ of femur length, with one long seta near distal margin. Tibia 2 about ⅔ of femur size, with one long seta on distal half rising from low tubercle. Tarsus short, trapezoid, with one ventrodistal spine. Propodus about 0.9 times as long as tibia 2, sole straight, with strong heel carrying 2 large heel spines followed by 2 smaller spines; sole carrying 2 small spines on proximal 3
rd
directed distally. Lamina on distal part of sole, about ⅔ of sole length. Main claw almost reaching heel, straight with terminal bending. Auxiliary claws present, very small.
MEASUREMENTS (mm). Trunk 0.44; abdomen 0.18; proboscis 0.25; chelifore 0.26; coxa 1 0.10; coxa 2 0.17; coxa 3 0.13; femur 0.41; tibia 1 0.32; tibia 2 0.3; tarsus 0.05; propodus 0.22; main claw 0.13.
Sexual dimorphism
Females with dilated femorae, no oviger.
Individual variability
Number of propodus heel spines variable, with 2 or 3 large spines and 2 or 3 smaller spines. Sole spines also variable in number, 1 or 2.
Remarks
Because the
holotype
is considered to be lost (
Müller & Krapp 2009
and MNHN collections data), we propose the selection of a new specimen from type locality (
Martinique
, southern Caribbean coast) to designate as a
neotype
.
Fig. 24.
Anoplodactylus micros
Bourdillon, 1955
, neotype, ♂, MNHN-IU-2016-1325.
A
. Body, dorsal view.
B
. Body, lateral view (same scale as A).
C
. Proboscis in ventral view (same scale as A).
D
. Ocular tubercle, frontal view.
E
. Oviger.
F
. Second leg.
G
. Cement gland opening of second leg.
H
. Coxa 2 of third leg.
I
. Tarsus and propodus of second leg.
J
. Chelifore.
According to
Müller & Krapp (2009)
, the two similar species
Anoplodactylus micros
and
A. bahamensis
can be distinguished based on the setae on the ventral side of the proboscis in
A. bahamensis
. However, both species exhibit setae in Madibenthos material. The species differ in two aspects: (i) the most obvious is the size of the specimens, the trunk of
A. micros
in the present material and in the original description being about half as long as
A. bahamensis
as measured by
Child (1977b)
; (ii) the cement gland opening is larger in
A. bahamensis
than in
A. micros
, although in some specimens this distinction may be tricky (
Fig. 20
). Regarding molecular data, the two species are clearly distinct (interspecific p-distance = 0.077– 0.1). Interestingly, within the material identified as
A. micros
the presence of two clusters (Sabroux
et al.
2019) with p-distances similar to that between
A. micros
and
A. bahamensis
(intercluster p-distance =
0.077
–0.079
) suggests that there may be at least two cryptic species. We thus informally describe two groups: group 1 includes the
neotype
, MNHN-IU-2016-1325, and specimens MNHN-IU-2016-802 and MNHN-IU-2016-1387, and group 2 is only represented by MNHN-IU-2016-804 (see Appendix for complete list).
The species
Anoplodactylus micros
was originally collected in Petite Anse du Diamant on the southern Caribbean coast (
Bourdillon 1955
). Here, the species was mostly found on the Caribbean coast, except
six specimens
sampled at Pointe du Vauclin and Presqu’Île de la Caravelle.
Distribution
So far only recorded from the Colombian Caribbean and
Martinique
.
Depth range
2–
30 m
.