A new genus and new species of Staphylinidae ( Coleóptera ) from Baltic amber

One new genus and nine new species of Staphylinidae are described from Baltic amber, namely Palaeosepedophilus gen.n. and the species P. succinicus sp.n., Lathrobium balticum sp.n., Lathrobium succini sp.n., Lathrobium ambricum sp.n., Lathro­ bium jantaricum sp.n., Sepedophilus balticus sp.n., Dictyon antiquus sp.n., Phymatura electrica sp.n., Aleochara baltica sp.n. Their affinity with related species is discussed.

The following paper presents the description of one new genus and nine new species from amber of Tertiary age (35-55 million years).These finds increase the total number of staphylinids described from Baltic amber to fifteen species and eleven genera.
The following institutions kindly contributed material for this study.The abbreviations cited below for each institution are used in all text citations.
ISEA Institute of Systematics and Evolution of Ani mals, Polish Academy of Sciences, Krakow.
UG Department of Invertebrate Zoology, University of Gdansk.

MATERIAL AND METHODS
For detailed viewing most pieces of amber were reshaped on a grindstone, then wet ground by hand to within about one mm of the fossil, using progressive grades of tungsten carbide paper, followed by polishing with cloth and leather impregnated with buffing rouge.Rectilinear facets were ground on three sides (dorsal, lateral, ventral) if possible.Oblique facets were some times ground in order to view the head, particularly on convex specimens.Observations were made using a Leica MZ 12.5 dis secting microscope, and high intensity incident light from a fiber optic illuminator.Much higher light levels are often required to view opaque fossils than is needed to view extant material.Measurements were made with an ocular micrometer.
Head slightly transverse (Fig. 2), about 1.18 times wider than long, moderately depressed, as wide as pronotum; eyes moderately large, protruding beyond lateral contours of head, length of each seen from above about 1.5 times shorter than postocular region; temples slightly arcuate; punctation moderately coarse and moderately dense.Antennae elongate, extending beyond basal 2/3 of pronotum, antennomere 1 robust and dilated apically, antennomere 2 elongate, about 2 times longer than wide, antennomere 3 more than 2 times longer than wide and longer than antennomere 2, antennomeres 4-11 moniliform, subequal in length.
Pronotum subquadrate (Fig. 2), about as wide as long, parallel-sided, only very slightly narrowed in straight line posteriorly; punctation coarse and moderately dense.
Type material.Holotype, female: No. 3232b (UG).Affinity.Lathrobium succini sp.n.resembles extant species L. castaneipenne Kolenati, 1846, but it differs externally by its smaller size, the darker elytra, the larger and more protruding eyes and by the finer elytral punctation.
Etymology.The specific epithet "succini" is an adjective from the Latin noun "succinum", meaning amber.4-5) Head subquadrate (Fig. 5), slightly longer than wide, moderately convex; eyes small, moderately protruding beyond lateral contours of head, length of each seen from above about 1.5 times shorter than postocular region; temples parallel-sided, hind angles broadly rounded; punctation fine and dense.Antennae relatively long, extending to the base of pronotum, antennomere 1 robust and dilated apically, antennomeres 2 and 3 subequal in length, about 2 times longer than wide, antennomeres 4-11 about 1.5 times longer than wide.
Type material.Holotype, female: No. 1/1529/187/00 (ISEA).Affinity.Lathrobium balticum sp.n. is similar to the extant species L. pallidum Nordmann, 1837, but it can be distinguished from that species by its larger size, darker colour, shorter tem ples, and by the finer punctation on pronotum and elytra.
Head subquadrate (Fig. 7), slightly longer than wide, moderately depressed, slightly narrower than pronotum; eyes moderately large, slightly protruding beyond lateral contours of head, length of each seen from above about 1.5 times shorter than postocular region; temples parallel sided, hind angles rounded; punctation fine and moder ately dense.Antennae elongate, extending to the base of pronotum, antennomere 1 robust and dilated apically, antennomeres 2 and 3 elongate, 2 times longer than wide, antennomeres 4-11 about 1.5 times longer than wide, spindle-shaped.
Pronotum quadrate (Fig. 7), about as wide as long, lat eral sides narrowed in straight line to rounded hind angles; punctation moderately fine and moderately dense.
Type material.Holotype, female: No. 1161 (UG).Affinity.Lathrobium jantaricum sp.n. is similar to L. bal ticum sp.n., but it differs externally from the mentioned species by shorter antennae, shorter pronotum with lateral sides more narrowed posteriorly, longer elytra and denser punctation on elytra.
Etymology."Jantar" is an old Lithuanian name for amber.
Head quadrate (Fig. 9), nearly as long as wide, moder ately depressed, as wide as pronotum; eyes moderately large, slightly protruding beyond lateral contours of head, length of each seen from above about 1.5 times shorter than postocular region; temples parallel-sided; punctation fine and moderately sparse.Antennae very long, extending beyond basal 1/3 of elytra, antennomere 1 robust and dilated apically, antennomeres 2 and 3 elon gate, subequal in length, about 2 times longer than wide, antennomeres 4-11 spindle-shaped.
Pronotum elongate (Fig. 9), about 1.3 times longer than wide, sides narrowed in straight line to rounded hind angles; punctation coarse and moderately dense.
Abdomen subparallel-sided, slightly diverging toward apex, widest at level of tergite 6; punctation fine and dense.Affinity.Lathrobium ambricum sp.n.differs from the extant species of Lathrobium by the conspicuously thickened first antennal segment.In general appearance the new species is similar to L. jantaricum sp.n., from which it can be readily dis tinguished by the more transverse head, longer and more nar rowed posteriorly pronotum and by the parallel-sided elytra.
Etymology."ambricum" is an adjective derived from the English noun "amber".
Elytra transverse, about as long as pronotum at midline, narrowed posteriorly; punctation fine and dense, pubes cence short and moderately dense.Wings fully developed.
Abdomen acuminate to apex; punctation fine and dense, pubescence very short, fine and dense.
Affinity.The type species clearly represents a genus in the Tachyporini, very close to Sepedophilus Gistel, 1856 andEuconosoma Cameron, 1918.It differs from both genera as the protibiae lack rows of spines along the outer margin and in the compressed ventro-dorsally, axe-shaped last segment of its max illary palpi.
Pronotum transverse and strongly convex, without lat eral setae, widest near base, lateral sides arcuately nar rowed towards anterior margin, base truncate, hind angles broadly rounded; punctation fine and moderately dense, pubescence fine, short and dense.
Elytra quadrate, narrowed posteriorly, about as long as pronotum at midline; punctation fine and dense, pubes cence fine and dense.Wings fully developed.
Elytra transverse, at sides about as long as pronotum at midline, at suture shorter than pronotum at midline, nar rowed posteriorly, postero-lateral angles distinctly sinuate; punctation fine, very dense and asperate, pubes cence short and fine.
Abdomen acuminate towards apex, tergite 7 longer than two preceding segments combined; punctation fine, very dense and slightly asperate.
Etymology.The name of the new species is the Latin word "antiquus" -meaning old, ancient.
Elytra transverse, about 1.7 times wider than their length at sides, at suture slightly longer than pronotum at midline; punctation moderately coarse, dense and asper ate.
Type material.Holotype, female: No. 296 (UG).Affinity.The new species should be assigned to the genus Phymatura on the basis of diagnostic characters, especially the tarsal formula (4-4-5), transverse pronotum with not visible epi pleura, large eyes, basal segment of metatarsus subequal in length to following two tarsal segments combined.In general appearance the new species is similar to the extant species P. brevicollis (Kraatz, 1856), but differs by its smaller size, the Description.Length ca.2.0 mm.Body robust (Fig. 25), parallel-sided, moderately convex; ground colour brown, legs red, antennae black with antennomeres 1-3 red.
Head transverse, narrower than pronotum, widest across eyes; eyes large, strongly protruding beyond lateral contours of head, length of each seen from above about 3 times longer than postocular region.Antennae short (Fig. 26), increase in width apically, antennomere 3 shorter than 2, antennomeres 4-10 transverse, antennomere 10 about 2 times wider than long, antennomere 11 conical, as long as two preceding together.
Pronotum transverse, convex, as wide as elytra, widest in posterior 1/3, lateral sides arcuate, more strongly nar rowed towards apex than base; punctation moderately coarse and moderately dense.
Elytra transverse, about 1.3 times wider than long, at sides about as long as pronotum at midline, slightly dilated posteriorly; punctation moderately fine, moder ately dense and asperate.
Abdomen parallel-sided, bases of tergites 3-5 each with fine transverse impression; punctation fine, dense and slightly asperate.Affinity.The new species should be assigned to the genus Aleochara on the basis of diagnostic characters, especially the maxillary palpi with 5 palpomeres.Externally, Aleochara bal tica sp.n.resembles the extant species A. moesta Gravenhorst, 1802, but it may be readily distinguished from that species by its smaller size, darker elytra, coarser pronotal punctation and by finer elytral punctation.