Further records of species of Gennadas (Crustacea, Decapoda, Dendrobranchiata, Benthesicymidae) in the Mexican Pacific
Author
Hendrickx, Michel E.
text
Zootaxa
2015
3980
3
417
426
journal article
10.11646/zootaxa.3980.3.5
969ad5e9-872c-47ef-b03e-09ebae3db5fe
1175-5326
238377
91FDD496-F465-4CAE-86A5-B7510C63DE53
Gennadas sordidus
Kemp, 1910
Gennadas sordidus
.—
Burkenroad, 1938
: 57
, fig. 1.
Hanamura, 1983
: 57
, figs. 4 d–f. Hendrickx & Estrada–Navarrete, 1989: 107 (list); 1996: 34, figs. 9, 19, 22
C. Guzmán & Wicksten, 2000
: 929
.
Wicksten, 2002
: 130
; 2012: 24, fig. 5C, D. Hendrickx, 2005: 161 (list); 2013: 441.
Guzmán, 2008
: 29
.
Material examined
.
183 specimens
.
TALUD
III. St. 13 (
23º38'30"N
107º58'48"W
),
August 18, 1991
, 2 M (CL
7.9–8.3 mm
) and 5 F (CL
6.4–9.9 mm
) (EMU–10877), and
8 juv.
(CL
2.9–5.7 mm
), 19 F (CL
5.7–10.9 mm
) and 14 M (CL
3.9–10.4 mm
) (EMU–10878) IK operated between surface and
720 m
; St. 19 (
25º12'N
109º07'W
),
August 20, 1991
, 7 M (CL 5.18–10.0 mm) and 10 F (CL
5.81–8.40 mm
), IK operated between surface and
410 m
(total depth:
920 m
) (EMU–9961) (id. J.
Flores
A.).
TALUD
IV. St. 15 (
23º23'30"N
107º47'48"W
),
August 24, 2000
, 2 F (CL
7.9–10.2 mm
), MN operated between surface and
1500 m
(total depth:
2350 m
) (EMU–10914–A); St. 18 (
24º15'12"N
108º17'10"W
),
August 25, 2000
, 2 M (7.4–9.0 mm) and 3 F (6.5–8.0 mm), BS operated at
908–944 m
(EMU–5985–A); St. 19 (
24º15'18"N
108º24'06"W
),
1 juvenile
, BS operated at
1196–1200 m
(EMU–5985B); St. 22 (2417'20"
N 10850
'30"W),
August 26, 2000
, 1 M (CL
7.3 mm
) and 1 F (CL
9.8 mm
), MN operated between surface and
1325 m
(EMU–10914–B).
TALUD
VII. St. 5 (
22º00'24"N
106º39'54"W
),
June 5, 2001
, 1 F (CL
6.5 mm
), BS operated at
1490–1520 m
; St. 19 (
24º16'12"N
108º23'42"W
),
June 7, 2001
, 2 M (CL
8.3–9.1 mm
) and 3 F (CL
7.35–8.30 mm
), BS operated at
1160–1180 m
(EMU–6693); St. 20 (
24º14'48"N
108º35'12"W
),
June 7, 2001
, 8 M (CL
7.5–10.5 mm
) and 6 F (CL
7.7–10.2 mm
), BS operated at
1480–1520 m
(EMU–5984); St. 27 (
25º01'30"N
109º12'W
),
June 8, 2001
, 2 M (CL
9.3–9.8 mm
) and 4 F (CL
6.5–9.3 mm
), BS operated at
1580–1600 m
(EMU–6697); St. 34B (
26º05'30"N
110º10'30"W
),
June 9, 2001
, 2 M (CL 8.0–
8.7 mm
), BS operated at
1500–1520 m
.
TALUD
VIII. St. 13 (
25º21'N
110º17'W
),
April 18, 2005
, 2 F (CL
9.09–9.91 mm
), BS operated at
1625 m
(id. J.
Flores
A.) (EMU–9962); St. 15 (
25º23'06"N
110º18'06"W
),
April 18, 2005
, 2 M (CL 6.8–8.0 mm), BS operated at
1030 m
; St. 16 (
25º24'48"N
110º34'48"W
),
April 18, 2005
, 1 M (CL 9.0 mm) and 1 F (CL 9.0 mm), BS operated at
1030 m
; St. 17B (
25º24'24"N
110º50'06"W
),
April 18, 2005
, 4 F (CL 6.0–10.0 mm), BS operated at
700–750 m
; St. 20 (
25º56'56"N
110º43'W
),
April 19, 2005
, 1 M (CL
8.8 mm
) and 2 F (6.0–
8.9 mm
), BS operated at
1140–1150 m
; St. 21 (
26º02'18"N
110º37'06"W
),
April 19, 2005
, 2 M (8.2–9.0 mm) and 4 F (CL 5.0–
8.9 mm
), BS operated at
1380 m
; St. 22 (
26º03'42"N
110º23'54"W
),
April 19, 2005
, 1 F (CL
9.1 mm
), BS operated at
2200 m
.
TALUD
IX. St. 2 (
24º38'42"N
109º17'36"W
),
November 11, 2005
, 2 F (CL
7.5–8.9 mm
), BS operated at
2195–2300 m
(EMU–8241); St. 10 (
24º56'24"N
110º16'42"W
),
November 12, 2005
, 1 M (CL 9.0 mm) and 2 F (CL 6.5–7.0 mm), BS operated at
969–1225 m
; St. 15 (
25º21'27"N
110º18'18"W
),
November 13, 2005
, 3 M (CL
8.1– 9.7 mm
) and 3 F (CL 8.0–
10.5 mm
), BS operated at
1985–2290 m
(EMU–8235); St. 16 (
24º23'48"N
110º36'42"W
),
November 13, 2005
, 1 M (CL
10.2 mm
) and 1 F (CL
10.1 mm
), BS operated at
997–1021 m
; St. 17 (
25º19'54"N
110º47'42"W
),
November 13, 2
M and 2 F, BS operated at
626–846 m
; St. 18 (
25º49'38"N
110º34'45"W
),
November 13, 2005
, 2 M (CL 7.0–
9.95 mm
), BS, depth unknown but>
500 m
(EMU–9963); St. 20–B (
25º58'07"N
110º40'04"W
),
November 14, 2005
, 1 M (CL
8.5 mm
), BS operated at
1229–1343 m
; St. 21–B (
26º04'42"N
110º34'48"
November 14, 2005
, 1 M (CL
6.8 mm
), BS operated at
1349–1369 m
.
TALUD
X. St. 5 (
28º14'50"N
112º24'53"W
),
February 9, 2007
, 1 damaged specimen (CL ca
8.5 mm
), BS operated at
820–837 m
; St. 8 (28º05'56N
112º26'50"W
) 1 M (CL ca
9 mm
) and 2 F (CL ca.
9 mm
), BS operated at
975–1007 m
(EMU–8200–B); St. 9 (
27º48'30"N
112º17'12"W
),
February 10, 2007
, 4 M (CL ca
8.5 mm
), BS operated at
1396–1422 m
; St. 13 (
27º49'46"N
111º43'18"W
),
February 11, 2007
, 1 M (CL 8.0 mm) and 3 F (CL 5.5–9.0 mm), BS, operated at
668–704 m
(EMU–8112); St. 14 (
27º44'53"N
111º36'58"w
),
February 11, 2007
, 3 M (CL
8.2–11.1 mm
) and 5 F (CL
7.2–9.8 mm
), BS operated at
905–943 m
(EMU–8091); St. 15 (
27º40'24"N
111º39'54"W
),
February 11, 2007
, 4 F (CL
6.5–8.5 mm
), BS operated at
1528–1530
; St. 17 (
27º08'N
111º44'10"W
),
February 12, 2007
, 2 F (CL
8.8–10.4 mm
) (EMU–8093–A), and 2 M (CL ca
8 mm
) and 2 F (CL ca
7 mm
) (EMU–8093–B), BS operated at
1289–1326
; St. 18 (
27º09'06"N
111º46'54"W
),
February 12, 2007
, 1 M (CL
9.6 mm
), BS operated at
1526 m
(EMU–8200–A); St. 19 (
27º36'08"N
111º36'08"W
),
February 12, 2007
, 2 F (CL 7.0 mm), operated at
1786–1816 m
(EMU–8092); St. 22 (
27º02'46"N
110º52'57"W
), 1 F (CL 7.0 mm), BS, operated at
1575–1586 m
; St. 25 (
26º39'04"N
111º18'20"W
),
February 14, 2007
, 1 M (CL ca
8 mm
) and 3 F (CL ca
8 mm
), BS operated at
837–840 m
; St. 26 (
26º35'16"N
111º05'59"W
),
February 14, 2007
, 3 damaged specimens (CL ca
8 mm
), BS operated at
1292–1301 m
.
TALUD
XII. St. 26 (
18º33'27"N
104º28'21"W
),
April 1, 2008
, 1 F (CL
8.2 mm
), BS operated at
2125–2165 m
.
TALUD
XV. St. 2 (
23º12'02"N
111º20'50"W
),
August 4, 2012
, 1 M (CL
8.6 mm
), BS operated at
1118–1150 m
(EMU–10868); St. 3 (
23º09'55"N
111º20'W
),
August 4, 2012
, 1 F (CL ca
7 mm
), BS operated at
1395–1465 m
(EMU–10874–A); St. 5E (
23º05'22"N
110º27'54"W
),
August 5, 2012
,
1 F.
(CL
10.1 mm
), BS operated at
948–954 m
(EMU–10874–B); St. 13 (
25º02'12"N
112º54'06"W
),
July 30, 2012
, 2 M (CL
7.1–9.4 mm
) and 1 F (CL
8.6 mm
), BS operated at
1210–1245 m
(EMU–10876–A); St. 15 (
25º18'50"N
113º12'17"W
),
August 2, 2012
, 2 F (CL ca
7 mm
; damaged), BS operated at
1246–1309 m
(EMU–10874–C); St. 17 (
26º20'14"N
114º13'07"W
),
July 31, 2012
, 1 F (CL ca
9 mm
), BS operated at
2111–2136 m
(EMU–10876–B).
TALUD
XVI–B. St. 1 (
28º27'24"N
115º48'55"W
),
May 23, 2014
, 1 M (CL
10.2 mm
), BS operated at
2038– 2054 m
(EMU–10869).
Distribution
.
Indo
–Pacific. In the eastern Pacific it has been recorded in the
San Pedro
Basin, California,
USA
, along the Baja California Peninsula, off the Revillagigedo Islands, and within the Gulf of California north to Tiburón Island; also reported from "Dowd Tablemount", off SW
Mexico
and off
Chile
(
Burkenroad 1938
;
Hanamura 1983
;
Hendrickx & Estrada-Navarrete 1996
;
Gúzman & Wicksten 2000
;
Guzmán 2008
;
Wicksten 2012
).
Distribution in western
Mexico
. As reported previously,
G. s o rd i d u s
is widely distributed throughout the southern and central Gulf of California, and along the west coast of the Baja California Peninsula (
Hendrickx & Estrada-Navarrete 1996
). Material examined herein includes the first record of this species for SW
Mexico
(
18º33'27"N
109º17'36"W
) (
Fig. 2
).
Remarks
.
Hendrickx & Estrada-Navarrete (1996)
reported new material of this species from 22 localities throughout western
Mexico
, except along the SW coast and north of Tiburón Island, Gulf of California. All their specimens had been captured with small and medium–sized pelagic gear operating from the surface to a minimum depth of
165 m
and a maximum depth of
300 m
.
Wicksten (2012)
provided a depth range of
0–915 m
corresponding to the deeper midwater trawl in which
G. s o rd i d u s
has been caught. There is, however, no precise information related to the depth of residence of
G. s o rd i d u s
except for the data provided by Hendrickx & Estrada- Navarrete (1996) indicating that it occurs in the epipelagic zone and maybe slightly deeper.
Gennadas sordidus
had previously been reported from five Mexican localities by
Burkenroad (1938)
. Material examined herein came from as many as 38 localities, 31 within the Gulf of California, 6 off Baja California, and one off SW
Mexico
(
Fig. 2
), and
G. sordidus
is therefore and by far the most common and abundant species of the genus in western
Mexico
. In this study,
76 males
and
107 females
were collected providing an overall sex ratio of 1:
1.4 in
favor of females.