Anamathia Smith 1885

Anamathia Smith, 1885

Anamathia SmITH, 1885: 493 [REpLACEmENT NAmE fOR Amathia ROux, 1828, A juNIOR HOmONym Of Amathia LAmOuROux, 1812, BRyOzOA]. PLACED ON THE OffICIAL LIST Of GENERIC NAmES IN ZOOLOGy (Op. 712: 336, 340, 347).

Type species. Amathia rissoana ROux, 1828, by mONOTypy. GENDER fEmININE. PLACED ON THE OffICIAL LIST Of SpECIfIC NAmES IN ZOOLOGy (Op. 712: 336, 340, 349).

Included species. Anamathia rissoana (ROux, 1828) [Amathia] (EA, MD) AND Anamathia hystrix (STImpSON, 1871) [Amathia] (WA).

Material examined. Anamathia hystrix (STIMPSON, 1871): 1 JUVENILE FEMALE (USNM 1191780), BRAZIL, MARANHÃO, R/V “OREGON”, STN 4226, 00°18’N, 44°17’W, 09.III.1963, W. SANTANA DET., 275M; 1 OVIGEROUS FEMALE (MZUSP 16952), BRAZIL, CEARÁ, CANOPUS BANK, 120 MILES OFF COAST OF FORTALEZA, 02°14’25”S, 38°22’50”W, J. COLTRO COLL., 6.IX.2005, ROCKy BOTTOM, 230 M; 1 MALE CL 26MM, CW 20 MM, 2 OVIGEROUS FEMALES (MZUSP 16953), CEARÁ, CANOPUS BANK, 120 MILES OFF COAST OF FORTALEZA, 02°14’25”S, 38°22’50”W, J. COLTRO COLL., 20-21.XI.2005, 240–260 M.

Anamathia rissoana (ROUX, 1828): 1 MALE, 1 FEMALE CL 22 MM, CW 19 MM (USNM 243897), NORTH ATLANTIC OCEAN, JOSEPHINE SEAMOUNT, R/V “METEOR”, STN 09C, 1967, 210–305M; 1 JUVENILE FEMALE (USNM 88703), SOUTHWEST OF AçORES, R/V “ATLANTIS”, CRUISE 152, STN 22, 34°05’N, 30°15’W, 20.VIII.1948, 152M; MALE CL 23 MM, CW 20 MM (USNM 152273), MEDITERRANEAN SEA, ITALy, SICILy, OFF PANTELLERIA ISLAND, R/V “LUCIOTTA”, STN RBM ITAL35, FROM 36 °22’40”N, 12°15’54”E TO 36°22’00”N- 12°17’30”E, 21.VI.1974, R. B. MANNING DET., 580– 600M.

Diagnosis. CARAPACE RATHER SWOLLEN, WITH HEPATIC, MESO-, METAGASTRIC, PROTO-, MESO-, METABRANCHIAL, CARDIAC, INTESTINAL SPINES VERy LONG; ROSTRUM VERy LONG, ACUTE. ANTEROLATERAL ANGLE OF THE BUCCAL FRAME PROTRUDED INTO STRONG, ACUTE SPINE. MALE CHELIPED PROPODUS AND MERUS SLENDER, AT LEAST TWICE AS LONGER AS THE FIXED FINGER. MALE ABDOMINAL SOMITE 1 WITH ONE VERy STRONG, ACUTE, AXIAL SPINE; SOMITE 2 WITH SMALLER, ACUTE, AXIAL SPINE; SOMITE 3 WITH ONE AXIAL KNOB. MALE THORACIC STERNITE 4 WITH TRANSVERSE RIDGE NEARLy STRAIGHT, NOT LOOPING AROUND THE ANTERIOR MARGIN OF THE STERNO-ABDOMINAL CAVITy; THORACIC STERNITE 8 EXTENDING LATERALLy BEyOND STERNO-ABDOMINAL CAVITy, LEFT UNCOVERED LATERALLy By ABDOMEN, VISIBLE IN VENTRAL VIEW. G1 REACHING FAR BEyOND THORACIC STERNAL SUTURE 4/5, RATHER STRAIGHT, CONVERGENT ANTERIORLy, TAPERING TO BLUNT TIP, LATERAL MARGINS ABRUPTLy CURVED INWARDS DISTALLy, KEEL WELL DEVELOPED (FIGS. 13C–F).

Remarks. AS PREVIOUSLy STATED, Anamathia HAS USUALLy BEEN CONSIDERED A SyNONyM OF Rochinia S. L. (RATHBUN 1925; GRIFFIN & TRANTER 1986; TAVARES 1991). NG et al. (2008: 102) LISTED Anamathia AS A VALID, MONOTyPIC GENUS, BUT MORPHOLOGICAL JUSTIFICATION FOR ITS VALIDITy REMAINED PENDING. IN THE PRESENT STUDy, WE ASSIGN A SECOND SPECIES TO THE GENUS, Anamathia hystrix (STIMPSON, 1871), AND PROPOSE THAT Anamathia DIFFERS FROM Rochinia S. STR. IN THE FOLLOWING SEVEN CHARACTERS: 1) MALE THORACIC STERNITE 8 EXTENDING LATERALLy A LITTLE BEyOND THE STERNO-ABDOMINAL CAVITy, SO THAT IT IS LEFT UNCOVERED LATERALLy By THE ABDOMEN AND THUS VISIBLE IN VENTRAL VIEW (FIG. 3C), VS. STERNITE 8 CONCEALED By THE ABDOMINAL SOMITES AND THEREFORE NOT EXPOSED VENTRALLy IN Rochinia (FIGS. 2C, 10A, B); 2) MALE THORACIC STERNITE 4 STRONGLy TILTED ANTERIORLy IN RELATION TO STERNITES 5–7 (FIG. 3B, C), VS. THORACIC STERNITE 4 ONLy GENTLy TILTED IN RELATION TO STERNITES 5–7 IN Rochinia (FIGS. 2C, 10A, B); 3) G1 REACHING FAR BEyOND THE THORACIC STERNAL SUTURE 4/5, KEEL WELL DEVELOPED (FIG. 13C–F), VS. G1 REACHING AT MOST SLIGHTLy BEyOND THE SUTURE 4/5, KEEL ABSENT IN Rochinia; 4) MALE CHELIPED PROPODUS AND MERUS REMARKABLy SLENDER, AT LEAST TWICE AS LONGER AS THE FIXED FINGER (FIG. 3A, B), VS. MERUS AND PROPODUS DISTINCTLy MASSIVE, MUCH LESS THAN TWICE AS LONGER AS THE FIXED FINGER IN Rochinia (FIG. 2A, B); 5) MALE ABDOMINAL SOMITE 1 WITH ONE STRONG, ACUTE, AXIAL SPINE; SOMITE 2 WITH A SMALLER, ACUTE, AXIAL SPINE; SOMITE 3 WITH ONE AXIAL KNOB EACH DECREASING IN SIZE DISTALLy, VS. MALE ABDOMINAL SOMITE 1 WITH SMALL AXIAL KNOB; SOMITES 2–3 SMOOTH IN Rochinia (FIG. 2A, C, F); 6) CARAPACE RATHER SWOLLEN, STRONGLy SPINOSE, ROSTRUM AND CARAPACE SPINES VERy LONG, ACUTE (FIGS. 3A, 12B), VS. CARAPACE DISTINCTLy PIRIFORM, RATHER LOW AND FLATTENED, SLIGHTLy HIGHER ALONG THE DORSAL MIDLINE OF THE CARAPACE, WITH SHORT SPINES IN Rochinia (FIGS. 2A, E, F, 12A); 7) ANTEROLATERAL ANGLE OF THE BUCCAL FRAME PROTRUDED INTO A STRONG, TRIANGULAR LOBE (FIG. 3D), OR INTO AN ACUTE SPINE AS IN A. hystrix, VS. ANTEROLATERAL CORNER SHOWING AS A ROUNDED, LOW LOBE IN Rochinia (FIG. 2B, D).

Anamathia AND Rochinia ALSO DIFFER IN THE FIRST ZOEAL STAGE (GUERAO & ABELLó 1996; PAULA 1996; LUPI & SPIVAK 2016) WITH LONG ROSTRUM IN A. rissoana, VS. ROSTRUM MINUTE IN R. gracilipes; AND DORSOLATERAL ABDOMINAL PROCESSES IN THE SOMITES 2–5, VS. DORSOLATERAL PROCESS ONLy IN THE SECOND ABODOMINAL SOMITE IN R. gracilipes.

Anamathia AND Scyramathia DIFFER FROM EACH OTHER IN SEVERAL ASPECTS. IN Anamathia DEVELOPING AND FULLy DEVELOPED SPECIMENS ARE SIMILAR IN GENERAL MORPHOLOGy (MURA et al. 2005), WITH THE CARAPACE PROVIDED WITH LONG HEPATIC, MESO- AND METAGASTRIC, PROTO-, MESO- AND METABRANCHIAL, CARDIAC, AND INTESTINAL SPINES (FIG.12B). IN CONTRAST, Scyramathia HAS SIGNIFICANT CHANGES IN MORPHOLOGy WITH GROWTH, DURING WHICH THE CARAPACE SUPRAORBITAL, HEPATIC, MESOGASTRIC, PROTO-, MESO- AND METABRANCHIAL, CARDIAC, AND INTESTINAL TUBERCLES OR SPINES BECOME LARGE, FLAT-TOPPED, LEAF-LIKE PLATES WHOSE CIRCUMFERENCES ARE BROADER THAN THE STEM IN FULLy DEVELOPED SPECIMENS (FIGS. 1A–D, 12C). IN ADDITION, IN Anamathia 1) THE HEPATIC SPINE IS VERy LONG, AND DISTINCT, NOT FUSED WITH THE POSTORBITAL SPINE (FIG. 12B), VS. ADULT SPECIMENS WITH POSTORBITAL SCUTELLATE PLATE AND HEPATIC BOLETATE ORNAMENTATION FUSED TOGETHER INTO A LARGE, LEAF-LIKE PLATE IN Scyramathia (FIGS. 1B, C, 12C); 2) THE ANTENNAL ARTICLES ARE NOT EXPANDED INTO LOBES (FIG. 3D), VS. LATERAL AND MESIAL MARGINS OF THE ANTENNAL ARTICLES 2 + 3 DISTINCTLy EXPANDED INTO LOBES IN Scyramathia (FIG. 1D); 3) THE MALE FOURTH THORACIC STERNAL TRANSVERSE RIDGE IS NEARLy STRAIGHT, NOT LOOPING AROUND THE ANTERIOR MARGIN OF THE STERNO-ABDOMINAL CAVITy (FIG. 3B), VS. THORACIC STERNITE TRANSVERSE RIDGE LOOPING AROUND FOLLOWING THE ANTERIOR MARGIN OF THE STERNO-ABDOMINAL CAVITy IN Scyramathia (FIG. 1D); 4) G1 KEEL WELL DEVELOPED (FIG. 13C–F), VS. KEEL ABSENT IN Scyramathia (FIG. 13A, B).