RECORD: Waterhouse, G. R. 1840. Descriptions of some new species of Carabideous insects, from the collection made by C. Darwin, Esq., in the southern parts of S. America. Magazine of Natural History 4: 354-362.

REVISION HISTORY: Scanned by John van Wyhe, transcribed (single key) by AEL Data 6.2008. RN1


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ART. IX.—Descriptions of some new species of Carabideous Insects, from the collection made by C. Darwin, Esq., in the Southern parts of S. America. By G. R. WATERHOUSE, Esq., Curator and Assistant Secretary as the Zoological Society.

THE insects I am about to describe belong to that great group of Carabidæ to which Dejean applies the name Féroniens, and to a section of that group, the species of which are distinguished by there being a kind of peduncle separating the thorax from the body,—giving to them a superficial resemblance to the Scaritidæ. This constricted portion between the thorax and abdomen is formed above by a produced portion of the elytra, which become suddenly narrow in front, and form, together with a portion of the mesothorax, a cylindrical neck, which apparently serves to give greater freedom, of motion to the fore part of the insect. Broscus cephalotes affords an example of this group in which Miscodera, Stomis, Cnemacanthus1, of Gray (which is the Promecoderus of Dejean), and Baripus, may also be included. These insects are most of them remarkable for the convex form of the thorax and elytra, the want of produced posterior angles to the latter, which is usually almost destitute of posterior foveæ, and dilated lateral margins—the dorsal channel moreover is generally very indistinct. In these respects the present group of insects affords a strong contrast to the more typical Feroniæ, if we may regard the species belonging to the genera Pterostichus and Omaseus as such.

In addition to the several genera (allied as it appears to me to Broscus) already mentioned, we are indebted to Mr. Curtis for the knowledge of three others possessing the same essential characters. I allude to the genera Odontoscelis, Cardiophthalmus and Cascellius, published by Mr. Curtis in the Linnean Transactions.2

The genus Odontoscelis, Curtis, is founded upon an insect brought by Capt. King from Valparaiso,—an insect which I have observed in many of our collections. In the 'Histoire Naturelle des Insectes' by MM. Audouin and Brullé3, a second species of the same genus is described and figured as an

1 Cnemacanthus gibbosus of Gray appears to me the same as the Promecoderus brunnicornis of Dejean, which is from Van Diemen's Land, and perhaps some other parts of Australasia, and not from Africa as has been stated. The genus Cnemacanthus of Guérin and Brullé being synonymous with Mr. Curtis' genus Odontoscelis, the species of which are from South America, must not be confounded with Cnemacanthus of Gray.

2 Vol. xviii. part. 2.

3 Tome iv. bis 2nd part, page 376, plate 15, fig. 4.

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illustration of Mr. Gray's genus Cnemacanthus, whilst in the same work will be found a true species of Cnemacanthus described and figured under the name Promecoderus Lottini1.

M. Guerin-Méneville, in the 'Magasin de Zoologie,'2 also figures and describes certain species of Odontoscelis under the name of Cnemacanthus, but this author perceives that the species of Cnemacanthus of the French authors differ in certain respects from the type of the genus figured in Griffiths' 'Animal Kingdom,' inasmuch as they have the anterior tibiæ prolonged externally; he states however that a small species which is found in Peru has not this external prolongation of the tibia, "et vient par conséquent se ranger exactement à côté du type de M. Gray. Nous ne pensons pas que cette légère différence soit suffisante pour motiver l'établissement d'un nouveau genre; nous nous en servirons pour diviser les Cnémacanthes en deux sections, ainsi qu'il suit." The author then proposes to distinguish those species which have the anterior tibiæ produced externally, by the name of Cnemalobus, retaining Cnemacanthus for Mr. Gray's species, and one other which he names Cnem. parallelus.

Now to those who are engaged in the study of the geographical distribution of species, it is most important to know what genera there are, species of which are found both in Australia and South America; it is highly desirable therefore that the difference in the structure of the anterior tibiæ of Cnemacanthus proper and Odontoscelis should be attended to, and that the Cnemacanthus parallelus be submitted to further examination, for Mr. Gray's genus does not differ only from Odontoscelis in not having the tibia produced externally—there are other very important differences—one of them indeed has been considered so important by Dejean,3 that he established two great groups which are distinguishable by it, and alluded to the tarsi of the intermediate pair of legs being dilated in the male sex, as well as the anterior pair; such is the case in Cnemacanthus proper, whereas in Odontoscelis only the anterior pair are dilated in the males: again, in Cnemacanthus the tooth in the notch of the mentum is short, broad, and truncated, whilst in Odontoscelis it is long and pointed.

1 Id. page 450, plate 18, fig.4.

2 Année 1838, liv. 2, pp. 9—13, plates 226 and 227.

3 This author places his genus Promecoderus (which, as before stated, is synonymous with Cnemacanthus of Gray) in his section 'Harpaliens.'

VOL. IV.—NO. 34. N.S. 2 X

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Genus.—ODONTOSCELIS, Curtis. Cnemacanthus, Andouin and Brullé. Cnemacanthus (sub-genus Cnemalobus) Guerin-Méneville.

Sp. 1. Odon. Tentyrioïdes, Curtis, Linn. Trans. vol. xviii. part 2, page 187, plate 15, fig. D.

Cnemacanthus obscurus (?), Brullé, Hist. Nat. des Insectes, tome iv. (bis), 2de livraison, page 377.

Two specimens agreeing in all respects (excepting in having a blueish tint on the under side of the body and legs) with Mr. Curtis's description, are in the collection of Mr. Darwin; they are from Valparaiso, the same locality as that given by Mr. Curtis.

Sp. 2. Odon. cyaneus.

Cnemacanthus cyaneus, Brullé, as above, page 376.

Much larger than the last and of a blue colour: its length is 10 lines (French measure), whilst Odon. Tentyrioïdes is about 8 lines. Inhabits Chili.

Sp. 3. Odon. Desmarestii.

Cnemacanthus (Cnemalobus) Desmarestii, Guerin-Méneville, Magasin de Zoologie, Année 1838, livraison 2me, page 9, plate 226 of class ix.

A very large species, from 26 to 30 'millemètres' in length. It is black above, tinted with green on the margins of the thorax and elytra. Inhabits Cordova.

These are all the species of Odontoscelis which I can find described; in the collection of Mr. Darwin there are four others, the characters of which I shall proceed to point out.

Sp. 4. Odon. Darwinii. Suppl. Plate xix. fig. 1.

Odon. latus, suprà lævis, nitidè viridis; pedibus corporeque subtùs violaceo-nigris; antennis, mandibulis, palpis, tarsisque piceo colore obscur tinctis.

This species is from to 10½ to 11½ lines in length, and from 4¾ to 4 1/3 lines in width. The upper parts of head, thorax, and abdomen are of a brilliant blue-green colour, the under parts are black, and the legs, antennæ, mandibles and palpi

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are pitchy black; a slight blueish tint is observable in certain lights on the under parts of the body, and on the under side of the prothorax there is a faint green hue: a few long hairs spring from the sides of the thorax and elytra, and also from the fore part of the head and above the eyes. The thorax is rather narrower than the elytra; its upper surface is convex, the sides are rounded, and so are the posterior angles, the hinder margin is slightly indented in the middle and near the posterior angles: the breadth of the thorax is about one third greater than its length; the dorsal channel is very indistinct, and there is a faint, posterior, transverse depression; along the outer margins are seven or eight large punctures. The scutellum is large and almost semicircular. The elytra are very convex and almost smooth; their length is less than one third greater than their breadth; on each elytron is a row of punctures, which commences at the shoulder, and ends nearly at the apex of the elytron; excepting near the shoulder (where the punctures are close to the outer margin) this row runs parallel with and at a short distance from the outer margin of the elytron, and on the margin itself a second row of punctures is observable; these are rather widely separated, and each puncture gives root to a long hair; a few punctures, also giving root to long hairs, are also observable on the shoulder, and again towards the apex of the elytra; these are situated above the first-described row.—There are no striæ on the elytra. On each of the abdominal segments is a transverse row of punctures, each having a hair like those on the outer margins of the elytra. The legs are rather densely clothed with short bristly hairs, especially on the tibiæ of the posterior and middle pair: on the outer margin of the anterior tibiæ there are no hairs; these tibiæ are much dilated at the apex, and the outer portion is produced and pointed; in the male it terminates nearly in a line with the apex of the basal joint of the tarsus, whilst in the female, where it is larger, it terminates opposite (or nearly so) to the base of the fourth joint of the tarsus: a row of punctures is observable on the under side of all the femora. Length of thorax in the female very nearly 3 lines; width of ditto 4 1/3 lines: length of elytra 6½ lines; width of ditto 4¾ lines in the female.

This species was obtained by Mr. Darwin at Bahia Blanca, North Patagonia.

Sp. 5. Odon. Curtisii.

Odon. latissimus, suprà lævis, niger; subtùs violaceo-niger: antennis, mandibulis, palpis, pedibusque piceo-nigris; thorace elytrisque apud marginem submetallicè relucentibus, illo subviridi, his colore purpurascente.

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This species is about equal in size to the last; and, like that, has a row of widely separated punctures near the lateral margins of the thorax; the punctures on the sides of the elytra, segments of the abdomen and femora, are the same; it differs however in being rather shorter, broader, rather less convex, and in having the upper parts of the body black and almost destitute of gloss. The thorax is rather convex, much broader than long, and equal in width to the elytra, or very nearly so; the sides and posterior angles are rounded, and the dorsal channel very indistinct; behind is a slight transverse indentation on either side, and extending nearly to the mesial line. Elytra rather convex, about one fourth longer than broad; smooth. Legs pitch-coloured; antennæ, palpi, and tarsi pitchy red. In one female there is a transverse row of punctures on the apical portion of the last segment of the abdomen; in a second about four oblong indentations are observable. A very indistinct greenish tint is observable near the margins of the thorax and outer margin of the elytra, and there is a faint blue tint on the under parts of the insect.—Total length, 11 lines; length of thorax 3 lines; width of ditto 4 2/3; lines; length of elytra 6¼ lines; width of ditto 4¾ lines. The specimens described are females.

Brought from Port Desire, Patagonia, by Mr. Darwin.

Sp. 6. Odon. striatus.

Odon. mediocritèr latus, niger, subtùs levitèr cæruleo-viridi tinctus; elytris distinctè striatis; striis haùd punctatis, interspatiis paululùm convexis; elytris ad marginem externum aliquantò violaceis.

Much less than either of the preceding, but larger than Zabrus obesus. General colour black, the under parts of the body (especially the thorax) tinted with greenish; sides of elytra and thorax tinted with purple or greenish. Thorax convex, about equal in width to the elytra, broader than long; the sides and posterior angles much rounded, the anterior portion emarginated; dorsal channel indistinct; posterior transverse depression scarcely visible. Elytra convex, their breadth about equal to two thirds of their length; distinctly striated, the striæ impunctate, and the interspaces convex. On the lateral margins of the thorax are six or seven large punctures, and close to the outer margin of the elytra is a longitudinal series of punctures; besides these there are two or three larger punctures near the apex of the elytra: a few large punctures are observable on the under side of the prothorax, and on each of the abdominal segments is a transverse row of punctures; these punctures however are not

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found on and near the mesial line: at the apex of the last segment there are from two to four punctures, on either side, and placed in a line: numerous hairs, springing from the punctures, are observable on the sides of the thorax and elytra. Length, 8¼ lines; width, 3½ lines.

In one of Mr. Darwin's specimens the striæ of the elytra are rather less distinct than in two others from which the above description is drawn up, and the interstices are flat on the fore portion of the elytra;—it is moreover of a smaller size, being only 7¼ lines in length.

Mr. Darwin found this species on a sandy plain at Bahia Blanca, N. Patagonia.

Sp. 7. Odon. substriatus.

Odon. ater, corpore breviusculo, convexo; elytris substriatis, striis indistinctis, interspatiis levitèr convexis.

Thorax rather narrower than the elytra, convex; the sides rounded, posterior angles also rounded, but very slightly prominent; dorsal channel indistinct; scarcely any trace of posterior transverse impression; elytra convex, their width equal to more than two thirds of the length; faintly striated, the interspaces slightly concave. Colour dull black; under parts with a blueish tint. The puncturing on the sides of the thorax, elytra, segments of abdomen, and femora, as usual. The hairs on the sides of thorax and elytra numerous.—Length from 6¾ to 7 1/3 lines; width from 2¾ to 3 lines.

This species is considerably smaller than either of the preceding; it is proportionately shorter than Odon. Tentyrioïdes, there is less space between the thorax and abdomen, and it is moreover distinguished by its striated elytra. Odon. Tentyrioïdes is smooth, or very nearly so; Odon. substriatus is rather delicately striated, and Odon. striatus is distinctly striated. Odon. substriatus is also intermediate in form between the other two species mentioned, being shorter and rather more convex than the first, and less convex than the last, from which it moreover differs in being narrower.

Genus.—CARDIOPHTHALMUS, Curtis.

Closely allied, as it appears to me, to Odontoscelis, is the genus above named,—a genus (with too long a name) established by Mr. Curtis, upon an insect brought from Port Famine by Capt. King.1 I had long since determined to found

1 Linn. Trans. xviii. part 2, page 184.

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a genus upon two species of Carabidæ forming part of a collection placed in my hands for description by Mr. Darwin; but upon studying Mr. Curtis's paper, I found that they possessed all the essential characters of his genus Cardiophthalmus. The chief differences between the insects of this genus and those of Odontoscelis, consist in the central tooth of the mentum being bifid; the legs and antennæ, much longer; the great length of the spines with which all the tibiæ, are furnished at their apex, and the proportionately narrower thorax, combined with the short, ovate and convex form of the body.—The anterior tibiæ are somewhat suddenly dilated at the apex (in the two species before me), and the external portion is slightly produced. The anterior femora in the species described by Mr. Curtis, is furnished with three or four small angular projections on the under side and near the base. I find the same character in one of the specimens before me, but in two other specimens (one of which is decidedly the same species as the first) there is merely a slight unevenness on that part of the femur,—possibly therefore it may be a sexual character: in the structure of the anterior tarsi there is no difference—they are all slender, and destitute of velvet-like pads or membranous appendages beneath.

Sp. 1. Card. Clivinoides, Curtis, Linn. Trans. xviii. part 2 page 185, plate xv. fig. C.

Sp. 2. Card. longitarsis. Suppl. Plate xis. fig. 2.

Card. nitidè niger, obscurè viridi tinctus; thorace, elytrisque convexis: elytris lævissimè striatis.

Thorax elytris angustior, lateribus rotundatis sic et marginibus, at leviter, posticè aliquantò attenuatus; sulco dorsali obscurissimo et post hune notâ transversâ insculptus. Elytra ad marginem externum seriatìm punctis, necnon segmentum abdominis ultimum, ad marginem posticum, notata.

Length, 11 lines; length of thorax 3 lines; width of ditto, 3 1/3 lines: length of elytra 6 1/3 lines; width of ditto, 4 1/3 lines: posterior tarsus very nearly 3 2/3; lines. Head about one third narrower than the thorax, the eyes but slightly prominent.—Thorax considerably narrower than the elytra, convex, the sides and posterior angles rounded; the dorsal channel indistinct; a distinct transverse impression near the hinder margin. The thorax is rather attenuated behind, and its broadest part is in the middle, or rather anterior to the middle. Elytra very convex, ovate, rounded at the apex; very faintly striated, the striæ, impunctate. General colour black,

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with a very indistinct metallic gloss; antennæ pitchy red; palpi pitch-coloured. On the third, fifth, and seventh interspaces between the striæ of the elytra a few widely separated punctures are observable, but these are confined to the apical portion of the elytra; moreover, with a tolerably strong lens some indistinct punctures may be perceived in the striæ: a series of rather widely separated punctures runs along the outer margins of the elytra, and on the apical portion are many subconfluent punctures. On the under side of each of the femora is a row of punctures; the terminal segment of the abdomen is margined with punctures, and there are tow punctures on each of the abdominal segments, one on either side of, and at some little distance from, the mesial line. The posterior tarsi are considerably longer than the tibiæ; each of the tibiæ is furnished at the apex with two very long spines. The antennæ are slender, and, if extended backwards, would reach beyond the hinder margin of the thorax.

This species is considerably larger than the Card. Clivinoides; it is of a broader form, and its legs and antennæ are longer, as well as the spines with which the former are furnished.

Sp. 2. Card. Stephensii.

Card. nitidè violaceo-niger; thorace convexo, attenuato, et posticè transversìm insculpto; corpore brevi, valdè convexo; elytris lævissimè striatis, striis vix apparentèr punctatis; interspatiis aliquantò convexis.

This species is much smaller than the last, and may moreover be distinguished from that and Mr. Curtis's species by the very convex, short, and almost rounded form of the body: its legs are shorter than in Card. longitarsis, and the posterior tarsi and tibiæ are equal in lenth. The thorax is short, convex, attenuated behind, and has the sides and posterior angles rounded; the dorsal channel is very indistinct; and there is a transverse depression near the posterior margin: the elytra are very convex, ovate, faintly striated, and the interstices are slightly convex: the striæ are indistinctly punctured, excepting on the apical portion of the elytra, where the punctures are distinct: some punctures are observable on the outer margin of each elytron and on the posterior margin of the apical segment of the abdomen; there are also two punctures on each of the other segments of the abdomen, as in Card. longitarsis.

Total length, 8½ lines; length of thorax 2¼ lines; width of ditto, 2 1/3 lines; length of elytra, 5 lines; width of ditto, 3½ lines.

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I have named this species in honour of the author of 'Illustrations of British Entomology,' to whom I am indebted for much information and kindness.

 

 

ART. X.—Descriptions of some new species of Coleopterous Insects. By EDWARD NEWMAN.

Natural Order.—CLERITES, Newman.

Genus.—HYDNOCERA, Newman.

THE genus Hydnocera was established in the 'Entomological Magazine,' vol. v. page 379. It approaches, in many essential characters, the genus Tillus of Fabricius, who probably would not have considered it as generically distinct. One of the species has been described by Germar in his 'Insectorum Species,' under the name of Clerus humeralis; and the same insect has also been labelled as the Tillus humeralis of Say, but I have no reference whatever to any description by the American entomologist. A second species (Hyd. serrata) has been named by myself, and recorded as captured by Mr. R. Foster, at Mount Pleasant, in Ohio : and three others are now added to the list. All the five inhabit the United States of North America.

The Count Dejean, in his 'Catalogue des Coléoptères,' has given to the genus the provisional name of Phyllobænus; this I learn from finding one of the species so named by Dr. Harris. I observe with regret that the plan of giving trivial names, without taking the trouble to secure them by the publication of a brief descriptive character, does not meet with that neglect and contempt which such a practice deserves; on the contrary, I have not unfrequently seen these spurious names attached at random to the genera and species that happen to stand unnamed in a cabinet; and names thus arbitrarily imposed in the first place, and subsequently applied by guess, are becoming rife in the majority of our collections of exotic Coleoptera.

Sp. 1. Hyd. humeralis. (Corp. long. ·23 unc. lat. ·06. unc.)

Clerus humeralis, Germar, 'Insectorum Species,' page 80.

Head large, transverse, black, covered with a grey pilosity, palpi and antennæ fulvous: the prothorax scarcely shorter

 


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