A second discovery of Lacertopontonia chadi Marin, 2011 (Crustacea: Decapoda: Palaemonidae), with remarks on its systematic position
Author
Fransen, Charles H. J. M.
Author
Reijnen, Bastian T.
text
Zootaxa
2012
3437
43
50
journal article
10.5281/zenodo.282111
3382880d-e21d-486c-a11c-9a253e786362
1175-5326
282111
Lacertopontonia chadi
Marin, 2011
(figs. 1, 2)
Lacertopontonia chadi
Marin, 2011
: 57
–68, figs 1–7.
Material examined
. 1 ovigerous female (pocl. 5.1)
RMNH
.
CRUS
.D.53857,
1 male
(pocl. 3.8)
OUMNH
.ZC.2012- 01-0064; stn SEM.14,
Malaysia
, Sabah, Ligitan Island, Ligitan 2,
04º09’35.8”N
118º52’22.2”E
;
3 Dec. 2010
; depth
15 m
; inside
Lopha cristagalli
encrusted by a red sponge; collected by Charles H.J.M. Fransen.
Paratypes
: 1 ovigerous female (pocl. 5.0),
1 male
(pocl. 4.0)
RMNH
.
CRUS
.D.54783;
Australia
, Great Barrier Reef, Lizard Island, lagoon, Channel, st. LI10–022, 14°
41.435 S
145°
27.912 E
;
28 Aug. 2010
; depth
14–15 m
; in wash-out from bivalve
Lopha cristagalli
growing on sea whip; collected by
Chad
Buxton.
Comparison with type-material
. The Sabah material generally corresponds to the
type
description by
Marin (2011)
. Several dissimilarities were noted in the present material.
The cutting edge of the fixed finger of both major and minor second pereiopods in both the Sabah male and female have the posteriormost tooth shallow and rounded, with many small simple denticles (fig. 1A, B). In the
paratype
male and female in the
RMNH
collections this feature is also present although erroneously described and figured by
Marin (2011: 67, figs. 5D, E; 6B-F)
as: “fixed finger (pollex) with two triangular acute teeth in proximomedial part”.
Figure 1
C shows the chela of the second pereiopod of the male
paratype
, originally figured by
Marin (2011: fig. 6d)
.
FIGURE 1.
Lacertopontonia chadi
Marin, 2011
. A, B, D, male (RMNH.CRUS.D.53857), Semporna; C, male paratype (RMNH.CRUS.D.54783), Lizard Island. A, second pereiopod, left major chela, median view; B, second pereiopod, right minor chela, median view; C, second pereiopod, right major chela, median view; D, telson. Scale bar = 1.0 mm.
The corpus of the dactylus of the third ambulatory pereiopod of the Sabah specimens, as well as the paratypic specimens, have fewer setae than drawn by
Marin (2011: fig.
5g
)
. A small, acute, forward directed tooth on a shallow basal protuberance is present on the proximal part of the flexor margin of the corpus of the dactylus (fig. 2A, B). In the
paratype
material an indistinct tooth on a shallow basal protuberance is visible in the third pereiopod of the ovigerous female, but not illustrated or mentioned in
Marin (2011)
.
In the fifth pereiopod, a rather small shallow angular tooth on a shallow basal protuberance is present on the proximal part of the flexor margin of the corpus of the dactylus (fig. 2C). In the male
paratype
specimen such a tooth is not present although a shallow basal protuberance can be observed (fig. 2D). The distoventral part of the propodus bears a small articulating spine (fig. 2C). Such a spine has also been observed in the
paratype
material (fig. 2D), but not illustrated or mentioned in
Marin (2011)
.
Telson with 3 pairs of submarginal dorsal spines and two pairs of distal spines (fig. 1D). The distalmost pair of dorsal spines can also be viewed as a subdistally and submarginally placed lateral pair of spines from the 3 distal pairs of telson spines as described for most
Pontoniinae
.
The exopod of the uropod is distinctly longer than the endopod. The exopod lacks the distolateral tooth but bears a small mobile distolateral spine. This distolateral mobile spine is present in the
paratypes
as well (fig. 2E), which contradicts the original description and figure (
Marin 2011: 67, fig. 3D, F
).
Colouration
. As described for
type
specimens from Lizard Island.
Host
. The infestation rate of the shrimp seems low in the Semporna area. After finding the present specimens in
Lopha cristagalli
, about
30 specimens
of the host were collected and inspected for the presence of shrimps, without any success.