Lamarckdromia, Guinot & Tavares, 2003

Guinot, Danièle & Tavares, Marcos, 2003, A new subfamilial arrangement for the Dromiidae de Haan, 1833, with diagnoses and descriptions of new genera and species (Crustacea, Decapoda, Brachyura), Zoosystema 25 (1), pp. 43-129 : 70-74

Genus Lamarckdromia n. gen.

( Fig. 10 )

Dromia – Lamarck 1818 pro parte: 264. — H. Milne Edwards 1837 pro parte: 177. — Haswell 1882b pro parte: 140. — Henderson 1888 pro parte: 3. — Ihle 1913 pro parte: 89. (Non Dromia Weber, 1795 ).

Dromidia – Stimpson 1858 pro parte: 225, 239. — Henderson 1888: 5. — de Man 1888 pro parte: 396, footnote. — Borradaile 1900: 571. (Non Dromidia Stimpson, 1858 ).

Dromidiopsis – Rathbun 1923a: 146. — Hale 1927: 110; 1941: 281. — Griffin 1972: 53 ( Dromiopsis , sic). — Forest 1974 pro parte: 103. — McLay 1993 pro parte: 120, 135, 137; 2001a pro parte: 79, 80. — McLay et al. 2001 pro parte: 733, 742. (Non Dromidiopsis Borradaile, 1900 sensu nobis).

TYPE SPECIES. — Dromia globosa Lamarck, 1818 by present designation.

SPECIES INCLUDED. — Dromia globosa Lamarck, 1818 (senior synonym of Dromidia excavata Stimpson, 1858 ).

A damaged, dry specimen of a male, identified as Dromia globosa and without locality, deposited in the Historical Reference Collection ( MNHN-B 22033), bearing the label “it is probably the material studied by H. Milne Edwards (1837: 177) and sent to M. de Man (1888: 396, footnote, pl. 18, fig. 1)”, is to be considered the type of the species and selected here as the lectotype.

ETYMOLOGY. — The genus Lamarckdromia n. gen. is dedicated to the eminent French naturalist Jean- Baptiste Pierre de Monet, chevalier de Lamarck (1744- 1829), who described several dromiid species. Gender: feminine.

DISTRIBUTION. — Australia.

DESCRIPTION

Carapace about as long as wide, convex; dorsal surface smooth, with regions not defined; subhepatic region hollowed; branchial groove marked and deeply notching external border. Anterolateral margin not joining orbit but reaching middle of pterygostomial border, and armed with only one blunt tooth; no tooth behind level of branchial groove; posterolateral margin short. Front narrow, appearing tridentate, with strongly deflexed rostrum and developed pseudorostral teeth; supraorbital tooth present; no suborbital and exorbital teeth. Orbits deep; eyes small. Antenna: urinal article with anterior part of beak raised; basal article with exopod developed and internal corner produced. Anterior margin of buccal frame formed by raised median wall and two acute lateral teeth. Mxp3: coxae separated by small gap.

Thoracic sternite 3 remaining exposed and visible dorsally, specially in males (sternites 1-2 at lower plane) ( Fig. 10A, D ). Thoracic sternite 4 narrow, with triangular anterior margin. Female sternal sutures 7/8 long, with apertures of spermathecae ending between P2, together on central prominence ( Fig. 10A ). When male abdomen is applied against ventral surface, extreme anterior part of sternite 4 and small part of episternite 4 remaining visible.

Male abdomen with all segments free; presence of extended pleural parts; telson much broader than long, rounded at tip. Male segment 6 slightly constricted in posterior part and rest of external borders subparallel. Vestigial pleopods absent in males. Uropods showing as ventral rounded/ ovate plates, well inserted, relatively developed but completely concealed ( Fig. 10B, C ). Uropods not involved in holding of abdomen. Abdominal holding provided by very sharp tuberculate prominence on P2 coxa, overhanging base of segment 6 ( Fig. 10B, D ).

Chelipeds not knobbed. P2 and P3 not knobbed nor nodose; propodus of P2 and P3 without distal spine; inner margin of dactylus armed with spines. P4 and P5 reduced, but P5 much longer than P4 and, when extended forward, reaching as far as the anterolateral tooth; merus and carpus being noticeably much longer than that of P4. P4 very short and stout, propodus wider than long. Subcheliform apparatus of P4 and P5 formed by one distal spine opposing the curved dactylus; three developed and subequal outer propodal spines on P4; on P5, only one long outer propodal spine.

Male P5 coxa with mobile penial tube ( Fig. 10D ).

Carrying behaviour

Sponges, compound ascidians.

REMARKS

Dromidiopsis globosa ( Lamarck, 1818) (see McLay 1993: 135, 137), from Australia, is excluded from Dromidiopsis sensu nobis ( Fig. 6 ) since: 1) uropods occur as completely concealed ventral plates (dorsal plates vertically oriented and well visible dorsally in Dromidiopsis ); 2) females sutures 7/8 only reach bases of P2 (see Forest 1974: pl. 6, fig. 4 as D. excavata ) (reaching bases of P 1 in Dromidiopsis ); 3) male abdomen has all segments free (segments 5-6 fused in Dromidiopsis ); 4) male telson is short and wide, bluntly rounded at tip (longer than wide, and more triangular in Dromidiopsis ); 5) abdominal holding is provided by tuberculate sharp prominence on P2, without involvement of the uropods (presence of a dentate crest on P2 and uropods involved in abdominal holding in Dromidiopsis ); and 6) there are differences in overall shape of carapace.

Since the uropods show as ventral plates in Dromidiopsis globosa , the species is excluded from the existing dromiine genera in which uropods show as dorsal plates (see Table 1). The uropods have been described as “small”, “concealed” or “absent” in about 10 dromiine genera. Despite the vagueness and imprecisions in some descriptions, D. globosa differs from those 10 genera in the details of the carapace, pereopods, thoracic sternum, and abdomen. Alone, the features of the carapace would be sufficient to place D. globosa in its own genus, Lamarckdromia n. gen. Additional characters mentioned as follows do not support the inclusion of D. globosa in the following genera: 1) Ascidiophilus Richters, 1880 ; 2) Austrodromidia McLay, 1993 sensu nobis; 3) Barnardromia McLay, 1993 ; 4) Dromidia Stimpson, 1858 sensu nobis; 5) Epipedodromia André, 1932 ; 6) Eudromidia Barnard, 1947 ; 7) Exodromidia Stebbing, 1905 ; 8) Haledromia McLay, 1993 ; 9) Platydromia Brocchi, 1877 ; 10) Pseudodromia Stimpson, 1858 ; 11) Speodromia Barnard, 1947 ; and 12) Tunedromia McLay, 1993 .

1) Ascidiophilu s (type species: Ascidiophilus caphyraeformis Richters, 1880 by monotypy) and 10) Pseudodromia (type species: Pseudodromia latens Stimpson, 1858 by original designation). In Dromidiopsis globosa ( Fig. 10 ): thoracic sternum “normal” (very narrow, specially sternite 4 showing as small piece in Ascidiophilu s and Pseudodromia ); male telson wider than long and rounded at tip (longer than wide and tip pointed in Ascidiophilu s and Pseudodromia ); holding of abdomen present, provided by sharp prominence on P2 coxa (absent in Ascidiophilu s and Pseudodromia ); when extended forward, P5 reaching anterolateral tooth (reaching as far as orbital angle in Ascidiophilu s or even more elongated in Pseudodromia ); and P4 and P5 propodus with distal spine opposing dactylus (no distal propodal spine opposing dactylus in Ascidiophilu s and Pseudodromia ). Another main difference is that the uropods show as ventral plates in Lamarckdromia n. gen. such as in Pseudodromia , while they are completely absent in both sexes in Ascidiophilu s.

2) Austrodromidia sensu nobis ( Figs 1 ; 2 ). In D. globosa : male abdominal segment 6 with external borders subparallel (deeply hollowed anteriorly and expanded posteriorly in Austrodromidia ); telson with its base not particularly enlarged (enlarged in Austrodromidia ); and female sternal sutures 7/8 ending together on central prominence between P2 (ending wide apart at level of P 2 in Austrodromidia ).

3) Barnardromia (type species: Cryptodromia hirsutimana Kensley & Buxton, 1984 by original designation), in which the sternal parts and abdomen are not figured ( Kensley & Buxton 1984: 193, fig. 4). In D. globosa : apertures of spermathecae ending together on central prominence between P2 (behind bases of P 1 in Barnardromia ); and P4 and P5 propodus with one distal spine opposing dactylus and three outer propodal spines on P4 and one outer propodal spine on P5 (dactyli of P4 and P5 opposed by single distal propodal spine in Barnardromia , in McLay 1993: 180, table 5).

4) Dromidia sensu nobis. In D. globosa : male uropods showing as ventral plates totally concealed ( Fig. 10B, C ) (ventral plates slightly visible dorsally in Dromidia , Fig. 5B, C ); vestigial pleopods absent ( Fig. 10C ) (Pl3-Pl5 present, in Dromidia , Fig. 5C ); male telson rounded at tip ( Fig. 10B, C ) (ending as sharp spine in Dromidia , Fig. 5B, C ); abdominal holding provided by tuberculate, sharp prominence on P2 coxa ( Fig. 10B, D ) (a strong spine on P2 coxa, directed backwards and partly overhanging abdomen in Dromidia , Fig. 5A, B ); and sternite 4 bluntly triangular ( Fig. 10A, D ) (rounded at tip in Dromidia , Fig. 5A, B ).

5) Epipedodromia André, 1932 (type species: Platydromia thomsoni Fulton & Grant, 1902 ). In D. globosa : uropods present, showing as ventral plates in both sexes (absent in ovigerous females in Epipedodromia ; absence to be verified in males); sternite 3 discernible ( Fig. 10A, D ) (sternite 3 developed and completely visible in Epipedodromia , Fig. 7A ); in females, posterior sternites gently tilted (sharply and vertically tilt- ed, with formation of brood chamber in Epipedodromia ); and apertures of spermathecae between P2, together on central prominence (apart, beneath thick medial bridge just behind P1, in Epipedodromia , Fig. 7A ).

6) Eudromidia (type species: Eudromia frontalis Henderson, 1888 by monotypy). In D. globosa : apertures of spermathecae ending between P2, together on central prominence (between P1, on a tubercle in Eudromidia ); and P4 and P5 reduced, but P5 reaching anterolateral tooth (P4 and P5 smaller, P5 being filiform in Eudromidia , at least in E. frontalis ). In Eudromidia the uropods, which have not been figured, are poorly known; McLay (1993: 179) refers to the uropods as “very small, concealed”.

7) Exodromidia (type species: Dromidia spinosa Studer, 1883 by monotypy). In D. globosa : male telson rounded at tip (ending in spine in Exodromidia ); vestigial pleopods absent in males (Pl3-Pl5 present in Exodromidia spinosa (Studer, 1883) , or only Pl5 present in E. bicornis (Studer, 1883) and E. spinosissima ( Kensley, 1977)) ; thoracic sternite 3 dorsally visible, only by very small part, specially in males (largely exposed in Exodromidia ); and male sternite 4 not hollowed medially, almost completely covered by abdomen, and with triangular tip (deeply hollowed and remaining always partly visible when abdomen folded, and with truncate tip, in Exodromidia ). The shape of ventral uropods, partly or totally concealed, also distinguishes the two genera: showing as rounded/ovate plates, not really movable in Lamarckdromia n. gen. ( Fig. 10B, C ), as narrow and elongated plates in Exodromidia .

8) Haledromia (type species: Dromia bicavernosa Zietz, 1887 by monotypy). In D. globosa : apertures of spermathecae ending between P2, together on central prominence ( Fig. 10A ), while in Haledromia the apertures end as far forward as P1, on large tubercle.

9) Platydromia (type species: Dromidia spongiosa Stimpson, 1858 ), which has also ventral and concealed uropods. In D. globosa : sternite 3 with a small part visible, particularly in males ( Fig. 10A, D ) (largely exposed in both sexes of Platydromia , Figs 15A ; 16 ); sternite 4 triangular ( Fig. 10A, D ) (wide and with convex lateral margins in both sexes of Platydromia ); male telson rounded at tip ( Fig. 10B, C ) (ending in acute tip in Platydromia , Fig. 15B, C ); and apertures of spermathecae ending together, on central prominence between P2, Fig. 10A (ending together, on slight prominence between chelipeds in Platydromia , Fig. 16 ).

11) Speodromia (type species: Dynomene platyarthrodes Stebbing, 1905 by monotypy). In D. globosa : female uropods not visible dorsally (visible beneath setae in Speodromia , after Stebbing 1905: 60, pl. 17, as Dynomene platyarthrode s; according to McLay 1993: 182, table 5, the uropods are not visible in both sexes); apertures of spermathecae between P2 (between P 1 in Speodromia ); and P4 and P5 reduced, with P4 short and stout, P5 much longer than P4 and, when extended forward, reaching as far as anterolateral tooth (P4 and P5 dissimilar in size and shape in Speodromia : P4 short, thick and three-sided; P5 much more slen- der, specially last three articles).

12) Tunedromia (type species: Petalomera yamashitai Takeda & Miyake, 1970 , by original designation). Tunedromia is now known from females and males ( Takeda 2001). In D. globosa : uropods showing as ventral plates, relatively developed but completely concealed (absent in both sexes of Tunedromia ); and P5 propodus with one distal spine opposing the dactylus and one single long outer propodal spine (multiple propodal spines opposing the dactylus and several outer propodal spines in Tunedromia ).

Lamarckdromia globosa n. comb. has its subhepatic region deeply hollowed, which provided the specific name of excavata given by Stimpson (1858: 77, as Dromidia excavata Stimpson, 1858 , junior synonym of Dromia globosa Lamarck, 1818 ). The body and legs are covered by a dense, shaggy coat of setae, and the deflexed front portion of carapace is concealed by a transverse fringe of longer setae, giving it a unique appearance. Epipedodromia thomsoni (Fulton & Grant, 1902) has a similar hairy ridge, forming a ledge that limits the anterior margin of the flattened carapace.

Lamarckdromia globosa n. comb. is only known from Australia. It has direct development and broods its young ( Hale 1941: 281, figs 15, 16, as Dromidiopsis excavata ; McLay et al. 2001: 742, as Dromidiopsis globosa ).

Figures

FIG. 10. — Lamarckdromia globosa (Lamarck, 1818) n. comb., New South Wales, Port Jackson, det. Dromidia excavata Stimpson, McLay redet. Dromidiopsis globosa (MNHN-B 22041); A, 25 × 25 mm, thoracic sternum and spermathecae; B-D, 24 × 25 mm, extremity of abdomen in dorsal view, abdomen in ventral view, and thoracic sternum without abdomen. Abbreviations: a3, a6, abdominal segments 3, 6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; o, female gonopore; pr, holding prominence; pt, penial tube; s, aperture of spermatheca; t, telson; u, uropod; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 2.5 mm.

FIG. 6. — A, Dromidiopsis tridentata Borradaile, 1903, New Caledonia, LAGON, stn DW 554, ovigerous 12.7 × 12 mm (MNHN-B 22550), thoracic sternum and spermathecae; B, D. australiensis (Haswell, 1882), Australia, Queensland, Cape Bedford, D. J. G. Griffin det., 15.4 × 14 mm (AM P16598), thoracic sternum with abdomen. Abbreviations: a5, a6, abdominal segments 5, 6; cx1- cx5, coxae of P1-P5; e4, episternite 4; mxp3, external maxilliped; o, female gonopore; pr, holding prominence; s, aperture of spermatheca; t, telson (setae covering sternite 4 not shown); u, uropod; 4-8, sternites 4-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 2 mm.

FIG. 1. — Austrodromidia australis (Rathbun, 1923), New South Wales, off Eden, Goonambee, 1922, 29.5 × 33 mm (AM P5777); A, thoracic sternum, two front views; B, abdomen, dorsal view; C, abdomen, ventral view; note uropods showing as very narrow ventral plates. Abbreviations: a6, abdominal segment 6; cx1-cx5, coxae of P1-P5; e4, e5, épisternites 4, 5; mxp3, external maxilliped; pr, holding prominence; pt, penial tube; t, telson; u, uropod; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bar: 5 mm.

FIG. 2. — Austrodromidia octodentata (Haswell, 1882), South Australia, Kangaroo Island, Endeavour, Rathbun det. Cryptodromia octodentata; A, B, 39 × 42 mm (AM E. 801); A, thoracic sternum, two front views; B, abdomen, ventral view; note uropods reduced to nearly obsolete buds; C, 44 × 46 mm (AM P. P2311), thoracic sternum and apertures of spermathecae, covered with spermatic plug. Abbreviations: a6, abdominal segment 6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; o, female gonopore; pr, holding prominence; pt, penial tube; sp, spermatic plug; t, telson; u, uropod; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 5 mm.

FIG. 5. — Dromidia hirsutissima (Lamarck, 1818), “Cap de Bonne-Espérance”, 26.6 × 31 mm, lectotype (MNHN-B 22034); A, thoracic sternum, two front views; B, C, abdomen, dorsal and ventral views; note uropods showing as ventral plates, hardly visible dorsally. Abbreviations: a5, a6, abdominal segments 5, 6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; pr, spiniform holding prominence; pt, penial tube; v4, v5, elongated vestigial pleopods 4 and 5 (pleopods present also on segment 3); t, telson; u, uropod; 4-6, sternites 4-6; 5/6-7/8, thoracic sternal sutures 5/6-7/8. Dotted line indicates difference in level. Scale bars: 2 mm.

FIG. 7. — A, Epipedodromia thomsoni (Fulton & Grant,1902),Australia,Victoria, Port Phillip, 9 × 11 mm (BM 1884-39), thoracic sternum and spermathecae; B, Hemisphaerodromia monodus (Stebbing, 1918), Madagascar, Fort-Dauphin,Decary coll., det.H. abellana Barnard, 1954, 16 × 18 mm (MNHN-B 12725), thoracic sternum and spermathecae.Abbreviations: cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; o, female gonopore; r, medial ridge; s, aperture of spermatheca; 1-3, sternites 1-3; 4-8, sternites 4-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level.Scale bars: 2.5 mm.

FIG. 15. — Platydromia spongiosa (Stimpson, 1858) n. comb.; A, B, Saint-Paul Island, Brocchi det. Platydromia depressa Brocchi, 1877, Vélain coll., 178-1875, 11 × 14 mm (MNHN-B 12724); A, thoracic sternum, two front views, note sternite 4 medially hollowed; B, dorsal view of abdomen; C, Amsterdam Island, Ams-A4, 11.II.1971, Beurois coll., 13 × 16 mm (MNHN-B 12728), ventral view of abdomen, note uropods not visible dorsally and oriented forward, and the vestigial pleopods showing only as papillae on segments 3-4. Abbreviations: a2-a6, abdominal segments 2-6; cx1-cx5, coxae of P1-P5; e4, e5, episternites 4, 5; mxp3, external maxilliped; pt, penial tube; t, telson; u, uropod; v3-v5, vestigial pleopods 3-5; 1-2, sternites 1-2; 3-8, sternites 3-8; 4/5-7/8, thoracic sternal sutures 4/5-7/8. Dotted line indicates difference in level. Scale bars: 1 mm.

FIG. 16.— Platydromia spongiosa (Stimpson,1858) n.comb.,Saint- Paul Island, Vélain coll., 178-1875, Brocchi det. Platydromia depressa Brocchi,1877, 12 × 16 mm (MNHN-B 12724),thoracic sternum, two front views,and spermathecae.Abbreviations:cx1- cx5,coxae of P1-P5;e4, e5, episternites4,5;gy, episternalgynglyme receiving sternal articular condyle of the pereopod;mxp3, external maxilliped; o, female gonopore; s, aperture of spermatheca; 1-2, sternites 1-2;3-8, sternites 3-8;4/5-7/8, thoracic sternal sutures 4/5-7/8.Dotted line indicates difference in level.Scale bar:2 mm.