H. C. Fall.
Some Notes on Cercyon, with Descriptions of Three New Species.
Psyche 31:247-253, 1924.

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PSYCHE
VOL. XXXI. DECEMBER 1924 No. 6
SOME NOTES ON CERCYON, WITH DESCRIPTIONS OF THREE NEW SPECIES,
Tyngsboro, Mass.
Some recent correspondence with Mr. Chas. Liebeck of Philadelphia has led to a critical exmaination of certain of our species of Cercyon, the results of which it seems desirable to make known.
More than half (14 out of 25) of the Cercyons recorded in the Leng List are more or less common European species, and in most cases the identity of the North American and European forms can scarcely be questioned. Some exceptions however have been noted. Specimens carefully compared by Mr. Liebeck and, found to be identical with the melanocephalus and luqubris of the Horn collection have been sent me for examination. These, on comparison with the best European descriptions and with authentic European representatives of the species in my collec- tion, prove conclusively that the melanocephalus and lupbris of the Horn Synopsis1 are not the true European species of these names.
In the melanocephalus of Horn the palpi are said to be en- tirely pale. In the true melanocephalus they are black or dark brown. Ganglbauer, in his Kafer von Mitteleuropa, IV, p. 278, observes this fact and remarks in a foot note that C. melano- cephalus Horn=nanus Melsh and can not be the melanocephalus of Linnaeus.
The intimation here that the species should be known as nanus Melsh is of course based on the published Amer- ican synonymy. In the Crotch List of 1873, arid the Henshaw List of 1885, both melanocephalus L. and nanus Melsh appear. 1Trans. Am. Ent. Soc., XVII, Oct. 1890.




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248 Psyche [December
In Horn's paper of 1890 nanus is set down without remark as a synonym of melanocephalus but on what grounds it is impossible to say. There is not now a single discoverable example of any of Melsheimer's species of Cercyon either in the Melsheimer or Le Conte Collections. It is understood that Le Conte was free to transfer tjo his own Collection anything he wished from the Melsheimer Collection, and he himself has somewhere stated that he possessed the authentic types of Melsheimer, Haldemann and Ziegler. There are now in t'he Le Conte Collection specimens bearing name labels (in Le Conte's hand) of three of the Mels- heimer species-maculatus, rnundus and minusculus-but nothing bearing the name nanus Mels. So far as discoverable there is nothing in the label, type of pin or style of mount, to indicate that any of these specimens came from the Melsheimer collec- tion; if any such there are they must have been remounted by Le Conte.
It follows that in the case of nanus at least, there is no recourse but the original description, and this I do not hesitate to say does not agree with the melanocephalus of Horn. Mels- heimer's diagnosis is rather brief but he describes his insect as "deep glossy black" and remarks that the antennae are piceous. Melanocephalus Horn is on the other hand rather dull in lustre, the elytra, as in the true melanocephalus and pygmceus, rufous or yellowish with a scutellar triangular black cloud which may spread over the greater part of the disk but never involving the entire lateral and apical margins; furthermore the antennae are pale.
Fortunately however there is no need to consider nanus in this connection, for a careful study of descriptions convinces me that Horn's melanocephalus is really another of the European species-terminatus Marsh-which has hitherto not been rec- ognised in our fauna. This is of the same type and a close ally of melanocephal& and pygmceus, differing from the former in the smaller size, entirely pale palpi and antennae, and the ab- sence of the metasternal line extending obliquely forward to the front angles. The specimens sent by Liebeck as agreeing with Horn's melanocephalus all possess precisely these characters,



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19241 Some Notes on Ceryon 249
and fit in all other respects Ganglbauer's description of term- inatus.t
In passing it may be well to say that Horn is in error in saying that pygmceus may be distinguished from melanocephalus by its pale epipleura. The Epipleura are normally blackish in all three of the species here mentioned, which may be readily separated as follows. +
Metasternal area extended by an oblique line toward the anterior angle.
Size much larger-2.2 to 3 mm., palpi blackish. , . . . . . . . . , melanocephalus
Size much smaller, always less than 2 mm., palpi yellowish t,o brownish, the terminal joint darker. . . . . pygmceus. Metasternum without oblique line extending forward from the central area; antennae and palpi pale; length about 2 mm. terminatus.
Although I have seen no nat,ive specimens, it is by no means unlikely that melanocephalus L. may have been found or may yet occur in Arneric'a.
Cercyon opacellus new species.
This is the species described as lugubris Payk. in the Horn Synopsis, but the two seem to me quite certainly distinct, nor am I able to identify our North American form with any other European species.
In lugubris Payk. the head and prothorax are strongly shining, the surface polished without trace of aluta- ceous sculpture, the elytra alutaceous and conspicuously dull. In our species the entire upper surface is always finely alutaceous, t,he head and thorax scarcely more shining than the elytra; the form is also appreciably more convex. Horn's description is entirely characteristic and need not be repeated. Whether the true Iugubris Payk. (convexiusculus Steph.) really occurs with us I am unable to say. I have as yet seen no American examples. $Since writing the above I have received from Mr. Arrow of the British Museum a specimen of terminatus carefully compared by him with Marsham's, type, which completely substantiates my conclusions.



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Psyche
Cercyon minusculus Melsh.
In Horn's synopsis of the genus this species of Melsheimer is for the first time relegated to synonymy and declared to be the same as the European qranarius Erichs.
Careful comparisons
by Mr. Liebeck with the series of four specimens (Mass., Pa., D. C.) in. the Horn collection upon which his conclusions were based, and by myself with the series of minusculus, so labelled, in the Le Conte collection shows them to be identical. These and all examples of the very considerable series in the collections of Mr. Liebeck and myself agree in the strikingly deep and sharply impressed elytral striae, especially toward the apex. A European specimen of granarius in my own collection has the elytra much less deeply striate and the interspaces very finely punctulate, whereas in minusculus the punctures of the inter- spaces are much more distinct and scarcely at all finer than those of the prothorax. Granarius and minusculus are indeed closely allied, but so far as the evidence at hand goes I consider their identity unlikely, or at least unproven. Cercyon connivens new species.
A small species of the lugubris-granarius-minusculus type. Form rather broadly oval, slightly attenuate behind, very strongly convex, black, the sides of the prothorax very narrow- ly tinged with rufous, t,he elytra with a sharply defined apical pale space which extends froward along the outer margins to about the middle. Head and thorax polished, densely moderate- ly finely punctate, elytra finely alutaceous and duller, a little more shining however along the suture, the strise impressed and entire, a little deeper at sides and apex; interspaces sparsely punctulate, the punctures finer than those of the prothorax but quite distinct. Beneath piceous or rufopiceous, legs and an- tenner reddish brown, palpi a little paler; meso-and metaster- nal plates very densely and unusually coarsely punctate. Length 1.6 to 2 mm.; width 1. to 1.3 mm. Of t,his species I have seen a considerable series from Cam- den, Gloucester and Anglesea, New Jersey, mostly collected by



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19241 Some Notes on Cercyon 25 1
Mr. Liebeck and a single specimen from Wakefield, Mass. taken by myself. One of the Camden specimens is selected as the type; it bears date "xi-23."
From minusczilus the present species differs in being less broadly obtusely rounded behind; from both minusculus and granarius by the sharply limited apical pale area and the dis- tinctly alutaceous surface sculpture of the elytra; from opacellus by t>he non-alutaceous head and thorax, and distinctly punctate elytral interspaces, and from all allied forms by the more coarsely densely punctured st'ernal areas.
C. connivens is really by its polished head and thorax and alutaceous elytra more nearly allied to lugubris than to any of the above mentioned species, and perhaps most closely of all to subsulcatus Ray of the European fauna. The latter however is said to have the elytral interspaces not or scarcely detectably punctate, which statement is not properly applicable to our species.
Cercyon californicus new species.
Oval, a little attenuate posteriorly, form nearly as in tristis but slightly less convex.
Black, prothorax with either the entire
side margin or (typically) with only a spot at the front angles paler; Elytra with a distinctly limited pale area which extends forward along the side margins at least to the middle, and often quite to the base. Head and thorax distinctly alutaceous, finely numerously punctate; elytra visibly but as a rule some- what less distinctly alutaceous than the thorax, stria fine and very lightly impressed, becoming obsolete just before the apex; interspaces sparsely punctulate, the punctures general- ly a little finer than those of the prothorax; eighth interspace uniserially punctured. Body beneath piceous, the epipleura paler in those examples in which the pale color of the apex ex- tends forward to the humeri; legs reddish brown to piceous brown; palpi brown with the last joint darker; antenna rufo- testaceous, the club piceoys. ~esosternal area evenly oval, twice as long as wide, rather coarsely punctured; metasternal area more finely sparsely punctate.




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252 Psyche [December
Length 1.8 to 2.4 mm. ; width 1 to 1.3 mm. Calif ornia-Elsinore Lake 8-22-17 (type) ; Pomona ; San Diego; San Francisco. All collected by the writer. Although slightly less convex than most species of Horn's category "13" this species by all essential characters belong there and should stand next to tristis, from which and all others of the group it differs by having the prothorax more noticeably alutaceous than the elytra.
In one example from Pomona the alutaceous sculpture is equally developed over the entire surface. The species belonging to Horn's category "13" (except the very distinct navicularis) may with advantage be retabulated as follows :
Entire upper surface alupateous.
Alutapeous sculpture equally developed on thorax and ely- tra; form shorter and more convex (Eastern U. S.).opacellus. Alutaceous sculpture as a rule a little more distinct on the thorax; size a little larger, form evidently less convex (California). ....................... californicus. Head and thorax polished, elytra distinctly alutaceous. Elytral strise extremely fine, scarcely impressed, obsolete ..............................
toward the apex. tristis.
Elytral striae entire.
Elytral interspaces very finely to scarcely visibly punc- tulate.
................................
Striae fine.. lugubris.
...................
Striae much stronger. subsulcatus.
Elytral interspaces distinctly punctate, striee well im- ..................................
pressed.. connivens.
Entire surface shining and with at most but feeble traces of alutaceous sculpture on the elytra.
...
Elytral apex with sharply defined pale area. .floridanus. Elytral apex at most only diffusely and obscurely paler, often scarcely at all so.
Elytral striae fine, the interspaces much more finely ..........
punctate than the prothorax. granarius.
Elytral striae sharply an,d deeply impressed, the punc- tures of the interspaces nearly as coarse as those of ..........................
the thorax minusculus.




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- Some Notes on Cercyon
Cercyon maculatus Melsh.
Analis Horn nec Paykull., indistinctus Horn. The C. maculatus of Melsheimer is given in Horn's synopsis as a synonym of analis Payk.
The species which Horn thus
describes is undoubtedly Melsheimer's maculatus as accepted by Le Conte but is an entirely different thing from Paykull's analis. The latter is a narrower, blacker, more attenuate species, resembling more in gdneral aspect the species of the lugubris group than it does maculatus and allies. According to the books analis constitutes the subgenus Paracercyon ~'eidl., differing from all other European species in having the metasternurn an- gularly cmargi~ate between the middle cox% for the rbception of the point of the mesosternal plate. Mr. Liebeck writes me that there are three examples of the true analis (Phila. Neck) ip the Horn series of analis but he is of the opinion that these have been added since the Horn Revision.
The characters upon which indistinctus Horn was founded, viz-the color of the elytral apex and the punctuation of the eighth interspace, are variable and lie within the limits of varia- tion of maculatzis. Specimens identical with the type series of indistinctus have been sent me by Mr. Lie'beck and I do not hesitate to confirm his opinion to this effect.



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