P. J. Darlington.
A List of the West Indian Dryopidæ (Coleoptera), with a New Genus and Eight New Species, Including One from Colombia.
Psyche 43:65-83, 1936.

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West Indian Dryopidse
A LIST OF THE WEST INDIAN DRYOPIDB (COLEOP- TERA), WITH A NEW GENUS AND EIGHT NEW
SPECIES, INCLUDING ONE FROM COLOMBIA
Museum of Comparative Zoology, Cambridge, Mass. Since 1927, when I published a paper on the West Indian "Helmidse" or Helminae (Psyche 34, pp. 91-97), a consider- able amount of additional dryopid material has come to hand. Most of it has been collected by myself during a trip to Cuba, Jamaica, and Haiti which I was. enabled to make from August to November, 1934, through grants from the Milton Fund and Atkins Foundation of Harvard University. This paper is to report upon this material and to bring our knowledge of the West Indian fauna up-to-date by listing the species, sometimes with critical comments. It does not pre- tend, however, to be a complete revision. By the "West Indies" I do not mean to include Trinidad, which is South American both geographically and faunisti- cally. Among the Dryopidse, the genera Dryops, Elsianus, and Heterelmis occur in Trinidad (collected by me in 1929) but are not, at least as yet, known from the West Indies proper, and one of the Trinidad species of Helmis (s. lat.) belongs to a group not yet known from the West Indies. In my 1927 paper I stressed the relationship of the West Indian species with those of Texas. Actually, of course, many of the species show close relationship with Central America as well as Texas, and there are some South Ameri- can elements in the Lesser Antilles. The West Indian fauna and that of the adjacent mainland are still so imperfectly known that there is not much point in discussing affinities in more detail, except to note that the West Indian fauna is certainly depauperate.
The absence of Dryopidse in many rivers and brooks in the West Indies is a striking phenomenon, worth recording Pu&e 43:65-83 (1936). hup ttpsychu einclub org/43/43-065 html



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66 Psyche [June-Sept.
in detail. In Jamaica I looked carefully for the family in several rivers and mountain brooks on the south slope of the main range of the Blue Mountains, in the Hope River near Kingston, and in several small, clear, rapid rivers near Ocho Rios on the north coast, but did not find a single spe- cimen, although Dryopidse are known from the island. I vis- ited also the Rio Cobre above Spanishtown, which looked like good dryopid water but was too flooded for collecting. In Haiti I worked carefully in the river at Ennery and the brooks on Mt. Basil (northern Haiti), in the Riviere Cul de Sac and the Riviere Froide (near Port-au-Prince), and in various mountain brooks in the high Massif de la Selle (southeastern Haiti) up to over 6,000 ft. in the Riviere Blanche on the La Selle plateau, with equally little result. However, in the La Hotte region (southwestern Haiti) I found Dryopidse in every river and brook examined, from the Ravine du Sud at Camp Perrin, under 1,000 ft., to a small brook at Desbarrihre, just north of Mt. La Hotte, at about 4,000 ft., the highest running water I saw in the La Hotte region. Five genera and eight species of stream lov- ing Dryopidse were found in this region. Possibly extensive clearing of forests, resulting in heavy freshets, has elimi- nated the insects in places by tearing up the stream beds and destroying aquatic vegetation, while they survive where, as near La Hotte, the forest is mostly uncut or where conditions are favorable for some other reason. The proportions given in my descriptions have been deter- mined by actual measurements. The types of all new species are in the Museum of Comparative Zoology. I am much indebted to Mr. K. G. Blair for notes on some types in the British Museum.
Subfamily Psepheninse
Psephenus Hald
Although this genus is not known from the West Indies, an understanding of its secondary sexual characters is im- portant in dealing with its West Indian relatives. In Psephenus lecontei Lee. the s differs from the $ as fol- lows: average size smaller; prothorax less explanate at sides; pronotum less opaque; elytra slightly less. distinctly



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19361 West Indian Dryopids 67
substriate ; antennae slightly longer, heavier, and more nearly serrate; maxillary palpi longer, heavier, with last joint more triangular; front and middle tarsi not dilated but with soles first 2 joints with numerous rather short, slender papillae; middle coxse much more approximate, meslosternum between them narrower and more acutely impressed; abdomen with 7 ventral segments (6th showing only at sides of 7th, in emargination of apex of 5th), not 6 as in Q .
Pheneps n. gen.
Generally similar to Psephenus, but more slender; head free; cox= similar; last tarsal joint elongate, but not quite so much as in Psephenus ; epipleurse similar, nearly reaching apex of elytra ; sexual dimorphism of palpi, mesosternum, and apical segments of abdomen similar. Differs from Psephenus in clypeus and labrum nearly in plane of front, not bent under head; in very long antennae reaching to near middle of elytra at least in 8, with 1st joint long, slightly bent, slightly thickened, 2nd less than % as long, slightly thickened, 3rd about length of Ist, but more slender, about 4 times long as wide in 8, outer joints gradually shorter, subserrate at least in 8 ; differs also in sides of prothorax not explanate, and in basal joint front and middle tarsi 8 enlarged as well as with papillae, broadly oval, several times bulk of 2nd joint, deeply emarginate apically. Differs from Psephenops in very elongate antennae and in 2d joint 8 tarsi small, though with sexual papillae as in Psephenus. The genotype is
1. Pheneps gracilis n. sp. (PI. 111, fig. 5) Male only. Moderately slender, depressed ; dark grayish brown, mouth, bases of legs', last (sometimes) and apices of some or all other ventral abdominal segments testaceous ; upper surface finely and very inconspicuously punctate, with fine, short, more or less decumbent gray pubescence, the direction of which varies on the elytra to form an irreg- ular, variable, sericeous pattern in some lights. Head not quite 3/5 width prothorax; eyes large and prominent; clypeus very wide, short, free at sides; labrum equally



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68 Psyche [June-Sept.
wide and short; palpi and antennae ( 8 ) as described above. Prothorax transverse, ab'out 2/3 wider than long, moder- ately narrowed anteriorly, apex about 3/5 width of base; sides more or less unevenly arcuate, nearly parallel basally, not margined, not explanate; base lobed before scutellum, broadly emarginate at sides ; apex slightly arcuate ante- riorly; basal angles acute posteriorly but not much pro- duced, apical angles rounded-obtuse; disk more or less evenly convex, with faint longitudinal impressed line at middle near base. Elytra ample, together 3/10 wider than prothorax, sides slightly diverging in basal 1/^, broadly rounded to the independently rounded apices ; surface with faint, irregular lon(gitudna1 impressions or striae. Abdomen
below with 2 basal segments deeply emarginate at middle, 1st entirely hidden by cox= medially. Mesosternum and s tarsi as described above. Length 4 or slightly more; width 2 or slightly more mm.
Haiti : holotype s (M. C. Z. no. 21,785) and 5 s paratypes (1 in U. S. N. M.) from Tardieu, in the valley just north of Mt. La Hotte (Pie de Macaya), about 3,000 ft., Oct. 14, 1934, taken with a light at night in depressions on stones in the turbulent Rivihre Tardieu. The insects were a foot or so above water level on stones which were dry but entirely sur- rounded by water. They were apparently resting, but ran actively when disturbed. The 9 characters of the genus have been taken from the following species : 2.
Pheneps cubanus n. sp. (PI. 111, fig. 6) Female only. Moderately slender, depressed ; testaceous brown, paler below; upper surface dull and finely and densely roughened on pronoturn, less so on elytra, not dis- tinctly punctate ; pubescence fine, short, subdecumbent, mixed with some slightly longer hairs, not forming sericeous patterns in any light. Head about 3/5 width prothorax; eyes large and prominent; front slilghtly concave at sides, faintly convex at middle; clypeus very wide and short, free at ends ; labrum distinctly narrower ; antennae (last 5 joints missing) slightly finer and with slightly shorter joints than in gracilis; maxillary palpi shorter, finer, and with more oval apical joint. Prothorax transverse, about twice as wide



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19361 West Indian Dryopidse, 69
as long, strongly narrowed anteriorly from the acute basal angles; sides not margined, not explanate, slightly arcuate basally, more so anteriorly where rounded into front mar- gin; latter arcuate, almost lobed, at middle; base lobed before scutellum, broadly emarginate at sides ; disk rather irregularly convex 'but without distinct impressions. Elytra ample, together 1/3 wider than prothorax, formed as in gracilis but surface even less distinctly impressed. Abdo- men
( s ) with 6 ventral segments, 1st and 2nd not emar- ginate at middle. Mesosternum ( Q ) broader and less acutely impressed between middle cox2 than in gracilis ( 8 ) . Front and middle tarsi ( Q ) derider, about as in Psephenus, without sexual papillse. Length not quite 4; width not quite 2 mm.
Cuba: holotype Q (M. C. Z. no. 21,786) unique from Soledad, near Cienfuegos, Santa Clara, Nov. 2, 1926, taken by myself. I do not remember the circumstances of capture. Of the numerous characters which distinguish this species from pacilis as described, the different form of the pro- thorax (not subparallel near basle in cubanus) and the dif- ferent color and more regular pubescence may be presumed to be specific characters. The more densely roughened pro- notum, narrower labrum, and entire 1st and 2nd ventral segments of cubanm may prove to be either specific or sexual differences, probably the latter. The shorter, slightly differently formed antennae and palpi, the fewer ventral seg- ments, more widely separated middle coxse, and much smaller basal joint of front and middle tarsi, without papillae, are, by analogy with Psephenus, strictly sexual char- acters and are so treated in my generic description of Pheneps.
Psephenops Grouvelle
(Xexanchorinus Grouvelle)
Notes from the Leyden Museum 20, 1898, pp. 44 & 45. The gentoype of Pstephenops is P. mithi Grouv. All of the types of this species were 8 8. Champion (Trans. Ent. Soc. London 1913, p. 63, PI. 3, figs. 2 & 2a) believed he had a
Q Psephenops with dilated tarsi and 6 ventral seg- ments. However, Mr. K. G. Blair has kindly examined



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70 Psyche [ June-Sept.
Champion's specimen for roe and writes that he thinks it is undoubtedly a 8, with apical abdominal segments and mesostem between the cox= formed aa in x rt of allied genera. Actually the a of Psephenops, as shown by my P. haitianw (below), has slender tarsi and differs from the s rather strikingly in its larger size and differently formed prothorax. It happens that there is an insect, Xexumhor- inus htus Grouv., described from the exact locality of one of the types of Psephenops smitki, which differs from the latter about as my Q Psephemps huitimus differs from the 8, Mr. Blair has compared Xexanchorinus latus with Psephenoys smith! (types of both in British Museum) and writes that the antennae of the two are similarly constructed and the elytral sculpture much the same. Judging from the sketches in Mr. Flair's letter, the dimorphism of the pro- thorax is about as great as in the Haitian species, and I am convinced that Psephenops smithi is the s and Xexanchor- inas lotus the 9 of one apecies. The former name has page priority as to both genus and species.
In accordance with these conclusions, and taking into account the peculiar heteromerous structure of the 8 tarsi in P. haitfunus, the secondary sexual characters of Psephe- nops are these: $ smaller and narrower than s, with nar- rower and more rounded prothorax which is less explanate at the sides; mesoaternurn between middle cox= very nar- row in a, much broader in 9 ; 8 with 7, s with 6 ventral segments conformed as usual in Paepheninse; dimorphism of antennae and palpi less than usual in subfamily; 8 with first and second joints front and middle tarsi and either first and second or only first joint of hind tarsus dilated and conspicuously lobed below, with densely pubescent soles', 5 with slender and simple tarsi. It will be noted that all of these secondary sexual characters are either foreshad- owed or duplicated in Psephenus or Pheneps or both, and that sexual dimorphism of the prothorax occurs also in some species of Phanocerus.
3. Pseyhenops smithi Grouvelle s
(Xexancho~nus htus Grouvelle ( 9 ) )
L. c., pp. 45 & 46.
Grenada and St. Vincent. The type locality of X. latus is



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19361 West Indian Dryopk!s 71
Chantilly Estate (windward aide), Grenada, whence came at least one of the types of P. smithi. Mr. Blair writes that the hind tarsus of the 8 has two dilated and lobed joints, like the front and middle tarsi.
Psephenops maculiwllis n. sp. (PI. Ill, fig, 1) Not West Indian, but described here because it is the only typical Psephenops I myself have had for comparison with the new West Indian species.
Male only. Psephenus-like, rather depressed; brown, head black; pronoturn dull reddish testaceous, dusky across base, with large, round, shining, piceous mark at middle from apex to about 2/5 from base and extending in a "fie line on carina nearly to base; each elytron with a short testaceous fascia from near humerus obliquely back and inward; dorsal surface with fine, short, close pubescence, relatively sparse on pronoturn; head, middle of pronoturn, and elytra especially near base, decreasingly distinctly, finely, and closely punctate; lower surface dark gray, appendages brown. Head about 4/7 width prothorax ; eyes prominent; front transversely ridged between upper part8 of eyes ; clypeus broad and short; labrum much narrower ; antennae short, reaching to about basal angles of prothorax, 2 basal joints somewhat enlarged, 2nd slightly shorter than 1st or 3rd, outer joints progressively shorter to subapical (wider than long), apical slightly longer. Prothorax not
quite 1% times wide as long, much narrowed anteriorly ; sides straight anteriorly, strongly rounded before basal angles; latter right ; anterior angles very obtusely rounded ; base lobed at middle and @marginate at sides ; apex slightly arcu- ate ; lateral margins explanate basally ; disk convex, slightly impressed near basal angles and each side near base in areas equidistant from each other and sides, strongly car& nate at middle in basal 1/3. Elytra, together about 3/10 wider than prothorax, somewhat shorter than abdomen, broadly, independently rounded apically; surface with usual indistinct stria-like impressions. Palpi, mesosternum, and apical segments of abdomen (dissected) aa usual in 8 Psepheninse; 1st ventral slightly emarginate at middle; all



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72 Psyche [June-Sept.
tarsi with 1st and especially 2nd joints elongate, lobed, and with hairy soles. Length 2%; width 1 1/3 mm. Colombia: holotype $ (M. C. Z. no. 21,788) unique from Rio Frio, about 20 mi. south of Santa Marta, Prov. of Mag- dalena, Feb. 25, 1928, taken on a stone in the Rio Frio River.
Differs from Psephenops smithi Grouvelle and Ps. grow vellei Champion (I. c.) in color and in having the sides of the prothorax strongly rounded near the base. The poste- rior tarsi are like those of grouvellei as figured by Cham- pion.
4. Psephenops haitianus n. sp. (PI. 111, figs. 2 & 3) Psephenus-like, rather depressed ; dark brown, bases of legs., parts of lower surface, and base of elytra pale, pale area extending back (vaguely) on each elytron in a triangle 1/3 of length; upper surface roughened, especially on pro- notum of ?, not distinctly punctate, with fine, short, uni- form, subdecumbent pubescence. Head small, just over V2 ( $ ) or less than $$ ( s ) width prothorax ; eyes prominent ; front faintly concave; clypeus wide, short, free at ends; labrum narrower; antennae moderate, reaching well ( 8 ) or slightly ( 9 ) beyond basal angles of prothorax, first 2 joints rather stout, 2nd about V2 length Ist, 3rd \/^ longer than Znd, outer joints progressively slightly shorter. Prothorax transverse, over 2 ( 8 ) to about 2% ( s ) times wide as long ; much narrowed anteriorly ; sides not margined, not explanate, slightly and evenly arcuate
( $ ) or sinuate be-
fore the posterior angles ( 2 ) ; latter acute ; anterior angles very obtuse; base broadly lobed before scutellum, emarg-i- nate at sides ; apex nearly truncate ; disk convex, faintly de- pressed before posterior angles, very obsoletely carinate at middle of base. Elytra ample, together about 1/3 ( $ ) to Vy, ( 9 ) wider than prothorax ; sides nearly straight and slightly divergent basally, broadly rounded to the independently rounded apices; surface with faint, longitudinal, stria-like impressions, more distinct in s , in which alternate intervals are slightly elevated near suture. Length ( 8 Q ) about 2v2 & 3% ; width 1 2/5 & 2 1/10 mm. (exact measurement diffi- cult because of position of specimens).




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1936 ] West Indian Dryopidse 73
In addition to the differences in size, proportion, and sculpture, there are the following secondary sexual charac- ters: antennae and palpi relatively a little more elongate in 8, but not much modified otherwise; prothorax sexually dimorphic in form, also more rounded dorso-ventrally at sides in 8 , more angulate in 9 , especially anteriorly; meso- sternum very compressed between coxae in 8, much less in Q ; abdomen with 7 ventrals in 8, 6 (apical visible only by dissection) in s ; first ventral rather strongly emarlginate at middle in 8, much less in $ ; 8 with first and second joints front and middle tarsi but only first of hind tarsus dilated, lobed below at apex, and with pubescent soles; $ tarsi slender, as in Psephenus.
Haiti: holotype 8 (M. C. 2. no. 21,787) from Tardieu, just north of Mt. La Hotte, about 3,000 ft., Oct. 14, 1934, taken at night on a stone in the river with Pheneps gracilis; allotype s from a small brook a few miles northeast of Mt. La Hotte, about 3,000 ft., Oct. 12, taken by holding a net in the current below a leafy sappling which had fallen into the brook and which I combed out thoroughly. In spite of the differences between these specimens there are so many points of exact correspondence - in details of the pale mark on the elytra, for instance, and in the faint sub-basal carina of the prothorax - that I feel certain they are one species. The form of the 8 hind tarslus distinguishes this species from all other known Psephenops. Possibly the difference may eventually prove to be of generic value. Subfamily Dryopinse
5. Hexanchorus caraibus ( Coquerel)
Rev. Ma,g. Zo6l. (ser. 2) 3, 1851, p. 601, PI. 15, fig. 14 (Potamophilus) .
Described from Martinique and Guadeloupe. 6. Phanocerus congener Grouvelle
Notes from Leyden Museum 20, 1898, p. 46. Grenada: described from Balthazar (windward side). This species should be compared with P. clavicornis Shp. of Central and South America.




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74 Psyche
[June-Sept.
7. Phwerus hubbardi Schaeffer
Journ. New York Ent. Soc. 19,1911, p. 119. Jamaica and Haiti : described from the former without more definite locality. I have before me one 8 topotype (same data as type) borrowed from the United States National Museum and 12 8, 11 Q from the northeastern foothills of the Massif de la Hotte, Haiti, 2-4,000 ft., Oct. 10-24, 1934, taken on water weeds, stones, and logs at water level in various rivers and brooks.
These specimens are
much darker than the Jamaican one, perhaps because of their greater freshness, and have the elytra slightly more strongly punctate. They are not so punctate as in Ph. clavi- cornis Sharp from Devil's River, Texas ( s Q Q , det. Schaef- fer, borrowed from U. S. N. M.) , however. The females in the Haitian series have the prothorax slilghtly more elon- gate, with sides more sinuate, than the males, so that I had separated the sexes even before examining the genitalia. A somewhat similar sexual difference exists in clavicornis, but not in the following species. The 8 genitalia of all these species seem to be indistinguishable. 8. Phanocerus helmoides n. sp. (PI. Ill, fig. 4) Subparallel, rather elongate, convex; piceous brown, with fine, short, close pubescence ; appendages brown, tibiae, tarsi, and antenna1 club darker. Head 2/3 width prothorax. Prothorax subquadrate, VA. (more or less) wider than long, only slightly more narrowled in front than behind; sides slightly or moderately arcuate, straight or slightly sinuate before base and apex; posterior angles right, anterior slightly obtuse but moderately prominent; explanate side marlgins conspicuous in anterior 1/3 ; apex arcuate ; base strongly, sinuately lobed before scutellum ; disk convex, with fine median longitudinal line, fine puncture each side of middle before 'base, rather fine groove each side from base 1/6 from side forward and then outward to just be- hind apical angle. Elytra slightly wider than prothorax, stria1 punctures rather fine, especially apically, more as in hubbardi than clavicorwis. Length 2.3-2.8 by 1.1-1.2 mm. Haiti: holotype 8 (M. C. Z. no. 21,789) and 6 8 , 6 Q paratypes (pair in U. S. N. M.) from the northeastern



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1936 ] West Indian Dryopidz 75
foothills of the Massif de la Hotte, southwestern peninsula, 2-4,000 ft., Oct. 10-24, 1934, taken in the same situations as the preceding.
The relatively weak convolutions of the protho,rax dif- ferentiate this from clavicornis, hubbardi, and congener, and give it a slightly Helmis-like aspect. 9. Lutrochus genicuZatus Chev.
Ann. SOC. Ent. France (ser. 4) 4, 1864, p. 406 (Lutochrus) ; Grouvelle, Bull., Soc. Ent. France 1896, p. 17. Cuba and Haiti : described from the former without more definite locality. I have before me a specimen (over 4 mm. long) supposed to be from Cuba and one (3y2 mm.) from the northeastern foothills of the Massif de la Hotte, Haiti, about 3,000 ft., Oct. 12, 1929. These specimens differ from Zuteus Lee. of the United States just as described in Grou- velle's key (1. c.). The Haitian specimen was secured from the same fallen sappling which yielded the allotype of Pse- phenops haitianus. Another specimen was seen at the cross- ing of the auto road and Rivihre Glace a few miles away, but flew from the edge of my net before I could reach it. 10. Throscinus schwarzii Schaeff er
Journ., New York Ent. Soc. 12, 1904, p. 204. Jamaica (and Texas) : described from the latter, from Brownsville. I have specimens from Brazoria Co., Texas, and one from Kingston, Jamaica, Aug. 27-29,1934, taken in vegetation in the edge of a small pond. The Kingston speci- men is not quite so roughened above as the Texan ones, but agrees well otherwise.
11. Throscinus ~thiops n. sp. (Pl. 111, fig. 7) Elongate oval, convex ; rather shining black above, lower surface and appendages reddish except antenna1 club black ;