A new genus and two new species of hymenosomatid crabs (Crustacea: Brachyura: Hymenosomatidae) from the southwestern Atlantic and eastern Australia
Author
Santana, William
text
Zootaxa
2015
3905
1
91
106
journal article
10.11646/zootaxa.3905.1.5
a54d2f73-4c13-4ae9-8da8-0ba2eac39702
1175-5326
239542
F66C212C-1B72-44E1-B2F8-66215DBC6928
Teramnonotus gordonae
(
Monod, 1956
)
n. gen.
, n. comb.
(
Figs. 4A
,
5A
,
8A–C
)
Elamena
(
Trigonoplax
)
gordonae
Monod, 1956
: 469
, figs. 629–637.
Elamena gordonae
—
Lucas 1980
: 171
[pro parte];
Ng & Chuang 1996
: 6
[pro parte];
Yang & Sun 1998
: 2
;
Almeida
et al
. 2007
: 29
[pro parte]; Almeida & Coelho 2008: 197 [pro parte]; Coelho
et al
. 2008: 18 [pro parte]; Ng
et al
. 2008: 108.
Material examined.
Elamena
(
Trigonoplax
)
gordonae
Monod, 1956
: ovigerous female
holotype
cl.
3.1 mm
, cw.
2.6 mm
, West Africa, between Conakry and Monrovia, Debyser coll., 1–8.
iii.1948, 30
–
40 m
(MNHN-B25803);
Sierra Leone
, Trawler
Maid Honour
, J. Cadenat coll.,
1–8.iii.1948
, between
8º38'N
and
8º42'N
,
8–12 m
, female
paratype
(abdomen absent) cl.
2.4 mm
, cw.
2.2 mm
(MNHN-B25802, currently MNHN-IU-2014-4029).
Diagnosis.
Rostrum well detached from the carapace outline, long, outreaching by far the second antennular article, apex sharp. Pterygostomial lobes large, first ending in acute tip, second much smaller but well discernible, followed by strong branchiostegal carina extending posteriorly to level of P3/P4. Subhepatic lobes clearly of distinct sizes, first much larger, lobes visible dorsally. Antennules not visible dorsally when folded. Tuft of setae on metagastric region of carapace small. Cheliped fingers moderately curved, laterally compressed; fingers edentate along cutting margins, not interlocking distally; fixed finger distal end inflated, minutely serrate, denticles rounded. Male unknown.
Remarks.
Teramnonotus gordonae
(
Monod, 1956
)
n. gen.
, n. comb.
, described by
Monod (1956)
as
Elamena gordonae
from two females (one ovigerous) collected between Conakry and Monrovia, and from
Sierra Leone
, has never been reported from West Africa since its collection in 1948. The male of the species is currently unknown. In
T. gordonae
, the P2–P5 dactyli end in an acute unguis preceded by two ventral, subdistal spines.
Monod (1956: 470, fig. 630)
erroneously figured only one ventral, subdistal spine in P5, but his figure 636 of the P5 and his description of the pereiopods are correct: "
Péreiopodes grêles, avec au bord supéro-distal du mérus une forte saillie tuberculiforme; dactyles 3-dentés
(
1 apicale + 2 subapicales internes
)" (
Monod 1956: 472, fig. 636
).
Teramnonotus gordonae
(Monod)
has been mistakenly recorded as
Elamena gordonae
from
Australia
(by
Lucas 1980
) and from
Brazil
(by
Coelho Filho & Coelho 2002
;
Almeida
et al
. 2007
; Almeida & Coelho 2008; Coelho
et al
. 2008). The Australian and the Brazilian specimens actually represent two separate new species herein described.
Yang & Sun (1998)
commented on the supposed resemblance between
Elamena longidactylis
Yang & Sun 1998
, and
Teramnonotus gordonae
(
Monod, 1956
)
n. gen.
, n. comb.
(as
Elamena gordonae
). Their resemblance, however, is only superficial because in
E. longidactylis
(as typical for
Elamena
), the ocular peduncle is not fused to the carapace and is freely movable, and the female thoracic sternite 8 is not concealed by the carapace in dorsal and posterior views (in contrast to
Teramnonotus
n. gen
.
, see above). As stated by
Yang & Sun (1998)
, the examined male and female of
E. longidactylis
also have thinner dactyli with three subterminal teeth on their ventral surface (instead of two in
T. gordonae
). Both sexes nevertheless have one anterior prominent pterygostomial lobe followed by a much smaller one (as in
T. gordonae
).
Distribution.
So far known only from West Africa (between Conakry,
Guinea
and Monrovia,
Liberia
and from
Sierra Leone
), between 8 and 40 meters deep.