Arthur M. Chickering.
New Species of Erigone (Araneae, Linyphiidae) from Panama and the West Indies.
Psyche 77:131-146, 1970.

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NEW SPECIES OF ERIGONE
(ARANEAE, LINYPHIIDAE)
FROM PANAMA AND THE WEST INDIES*
BY ARTHUR M. CHICKERING
Aluseum of Comparative Zoology
In the course of my collecting activities for many years in Central America and the West Indies I have accumulated a considerable number of the small Linyphiidae assigned to the Mi~~yphantinae or frequently given independent family status (Micryphantidae). Among those are numerous interesting genera not well known from the Neotropical Region. Recently I have been able to separate out from the collection a number of specimens which I believe to represent new species of the genus Erigone which is well known in North Amer- ica. Descriptions of these are given in the following pages of this paper for the consideration of those who later continue the study of this genus. I feel certain that careful collecting in Central America and the West Indies will yield numerous additional species. Cuba, Haiti and the Dominican Republic should be espec'ally pro- ductive. More careful collecting and matching of males and females is much needed. My own studies of the genus have, thus far, pro- duced only a very small number of known females although other specimens have been under suspicion.
Grants GB-1801 and GB-5013 from the National Science Founda- tion have furnished financial aid for several collecting trips in Central America, the West Indies and Florida together with my continued research in the Museum of Comparative Zoology for nearly five and one half years. As I have repeatedly acknowledged in my published papers, I am deeply grateful for the help and en- couragement received from members of the staff of the Museum of Comparative Zoology extending over a period of many years. Genus Erigone Audouin, 1826
Erigone antegona sp. nov.
Figures 1-3
Holotype.
The male holotype is from the Panama Canal Zone, Forest Preserve, January 29, 1958. The name of the species is an arbitrary combination of letters.
*Manuscript received by the editor August 13, 1969. 131




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Figs. 1-3.
Erigone antegona sp. nov, Fig. 1. Carapace and eyes from above. Figs. 2-3. Left palp of holotype; prolateral and retrolateral views, respectively. Figs. 4-9. Erigone aptuna sp. nov. Fig. 4. Eyes from above; tipped backward slightly. Fig. 5. Right chelicera from in front. Fig. 6. Left palpal femur and trochanter; nearly ventral view. Fig. 7. Right palpal patella of holotype; retrolateral view. Figs. 8-9. left palpal tibia and tarsus; prolateral and retrolateral views, respectively.



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19701 Cbickering - Erigone 133
Description.
Total length 1.06 mm. Carapace 0.6 mm long; 0.45 mm wide opposite second coxae where it is widest; about 0.22 mm tall at beginning of very gradually declining ~osterior declivity op- posite interval between first and second coxae; broadly rounded in front ( Fig. I ) ; with a fairly well defined median thoracic groove ; without teeth along ventral margin. Eyes: eight as usual in the genus ; viewed from above, both rows moderately recurved ; viewed from in front, both rows moderately procurved. Ratio of eyes AME : ALE : PME : PLE = nearly 5 : 7 : 8 : 8. AME separated from one another and from ALE by a little less than their diameter. PME separated from one another by nearly their diameter and from PLE by about their radius.
Laterals separated only by a line. Central ocular quadrangle wider behind than in front in ratio of about I I
: 7; wider behind than long in ratio of about I I : 9. Height
of clypeus equal to a little more than four times the diameter of AME. Chelicerae: with three or four teeth in basal half of anterior surface (right and left sides differ somewhat) ; with three low and minute cusps along medial margin; fang groove well supplied with teeth but exact number not determined because of fragility of holo- type and lack of paratypes. Maxillae: robust; moderately conver- gent; without special modifications except that there appear to be a few obscure cusps. Lip : short; less than half as long as maxillae; deeply excavated in basal half. Sternum : scutiform; widest in an- terior quarter; quite convex; obtusely truncated and extended be- tween fourth coxae which are separated by a little less than half their width. Legs: 1423 in order of length; slender spines as usual in the genus. Palp: obscurely distinctive; the trochanter has a mod- erately well developed ventro-lateral projection; the femur has a series of four or five small ventral cusps each with a bristle; the patellar apophysis is much reduced; the tibia appears to be quite distinctive but its parts are so intimately related to corresponding parts of the tarsus that representation in a drawing is difficult; essen- tial parts of the tarsus represented in Figures 2-3. Abdomen: con- siderably smaller than cephalothorax and without special modifica- tions; essentially typical of males of the genus. Color in alcohol: Carapace dark brown with gray streaks radiating from the middle line of the thoracic region; with a moderate amount of black pig- ment in ocular region; sternum dusky brown; legs and mouth parts yellowish with dusky streaks; abdomen a dark, dusky brown, nearly black.
Diagnosis.
This species with its reduced palpal patellar apophysis



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134 Psyche [March
seems to belong in the group to which Erigone barrows! Ci-osby and Bishop and Erigone dentimandibulata Keyserling belong. Its inde-
pendent status as a new species is more or less clearly indicated by the body features and by the characters of the male palp. Records.
The female is unknown and there are no male paratypes. Erigone aptuna sp. nov.
Figures 4-9
Holotype.
The male holotype is from the Panama Canal Zone, Barra Colorado Island, August 15, 1954. The name of the species is an arbitra,ry combination of letters. Description. Total length 1.28 mm. Carapace 0.66 mm long; 0.54 mm wide; about 0.29 rnm tall shortly behind PME where it is tallest; no serrations observed along ventral margin; general features typical of the genus. Eyes: eight in two rows as usual ; viewed from above, anterior row definitely 1-ecurved, posterior rox slightly so. Ratio of eyes AME : ALE : PME : PLE = 4 : 6.5 : 6 : 6.5
(slight irregularities noted). AME separated from one another only by a broad line and separated from ALE by a little more than their radius; separated from PME by nearly their diameter (Fig. 4). ALE and PLE contiguous to one another. PME separated from one another by about two-thirds of their diameter and from PLE by a little less than their radius. Central ocular quadrangle wider behind than in front in ratio of 7 : 4; wider behind than long in ratio of nearly 7 : 6. Clypeus somewhat extended forward; with height nearly equal to three times the diameter of AME. Chelicerae: ver- tical ; nearly parallel ; with teeth on anterior surf ace essentially as shown in Figure 5 but there appear to be fewer teeth on the left than on the right; with teeth along the fang groove but exact number not determined because of fragility of holotype and lack of paratypes; no lateral striations observed. Maxillae: convergent ; essentially typical of the genus except that conspicuous teeth appear to be absent and with only sn~all cusps present. Lip: short; with swollen anterior border as usual in the genus. Sternum: convex; only a little longer than wide; extended between fourth coxae which are separated by nearly their width. Legs: I =423 in order of length; with slender spines, bristles, hairs and trichobothria. Palp: trochanter with the usual ventral protuberance; femur with inconspicuous teeth and cusps (Fig. 6) ; patella short and with a short, sharply pointed apophysis (Fig. 7) ; tibia more or less typical of males of the genus; tarsus complicated and obscurely distinctive (Figs. 8-9). Abdomen :



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Figs. 10-12.
Erigone bereta sp. nov. Fig. 10. Right cheliceral teeth along fang groove. Fig. 11. Right palp of holotype; retrolateral view. Fig. 12. Idem; dorso-prolateral view. Figs. 13-16. Engone autumnalis Emerton. Fig. 13. Left maxilla of male from Panama Canal Zone. Fig. 14. Epigynum of female from Panama; seen from below. Fig. 14a. Idem; from behind with posterior border lift<ed. Fig. 15. Left palp of male from Trinidad, W. I.; retrolateral view.
Fig. 16. Left palp of male from Puerto Rico; retrolateral view.




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136 Psyche [March
quite typical of males of the genus and without special modifications. Color in alcohol: carapace a very light yellowish brown with a very narrow median gray stripe and irregular radiating grayish lines; with a moderate amount of black pigment in the ocular area; sternum light grayish; legs and mouth parts yellowish with variations; ab- domen a light grayish on the dorsum and lateral sides and with more gray color irregularly distributed on the venter. Diagnosis.
This species appears to be more or less closely related to Erig-one tamazunchalensis Gertsch and Davis from Mexico but differs from that species in details of the male palp. Records. The female is unknown and there are no male paratypes. Erigone bereta sp. nov.
Figures 10-12
Holotype.
The male holotype is from Corozal, Panama Canal Zone, May 25, 1964. The name of the species is an arbitrary com- bination of letters.
Description. Total length 1.65 mm. Carapace 0.81 mm long; 0.58 mm wide opposite second coxae where it is widest; cephalic region considerably raised much as in Erigone denfigera 0. P.-C.; thoracic portion very gradually slanted to posterior border; ventral margin with a series of small teeth beginning opposite first coxae; with a moderately well defined median, longitudinal, thoracic groove. Eyes: eight in two rows as usual; with chitin raised and with dis- tortion of eyes; apparently both rows are curved essentially as de- scribed for Erigone antegona sp. nov. Ratio of eyes AME : ALE : PME : PLE = nearly 7 : 10 : 9 : 8. AME separated from one another by slightly less than their diameter; separated from ALE by slightly more than their diameter. PME separated from one another by about seven-ninths of their diameter and from PLE by about two-thirds of their diameter. Laterals as usual, separated only by a line. Central ocular quadrangle wider behind than in front in ratio of about 4
: 3; wider behind than long in ratio of about 6 : 5. Height of clypeus nearly equal to four times the diameter of AME. Chelicerae: well extended to expose fang, fang gi-oove and teeth; fang somewhat irregularly curved; fang groove with six promar- ginal teeth of which the fifth is the largest and four retromarginal teeth, all small (Fig. 10) ; front surface of each chelicera with five teeth along the lateral margin with the first very small and others much larger and hooked; apparently each chelicera also has two or



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19701 Checkering - Erigone 13 7
more very minute cusps each with a bristle and irregularly distrib- uted; the only striations observed are on the front surface and those are irregular and probably not used for stridulation. Maxillae: of typical shape; each with several small cusps four of which are grouped closely together with the others more widely distributed. Lip: short as usual; with basal half excavated. Sternum: of usual form; only very moderately convex; extended between bases of fourth coxae which are separated by slightly less than their width. Legs: 1~423 in order of length; patellae three and four each with a very slender dorsal distal spine; tibiae three and four each with a single slender, dorsal spine near proximal end; true spines not ob- served elsewhere. Palp: essential features of patella, tibia and tarsus shown in Figures I 1-12 ; the patellar apophysis is exteremely well developed; the tibia is quite distinctive; the femur has a series of minute cusps on its ventral surface and a weakly developed cusp at its base on the prolateral surface. Abdomen: a swelling appears in the middle of the venter just anterior to the genital groove; other- wise essentially typical of males of the genus. Color in alcohol: carapace brownish with darker streaks; sternum dusky brown; mouth parts yellowish brown; legs yellowish; abdomen yellowish on dorsum but grayish laterally and ventrally.
Diagnosis.
This species appears to be closely related to Erigone autumnalis Emerton. It differs from that species, however, in respect to the details of the palp, chelicerae a,nd maxillae. Records.
The female is unknown and there are no xiale paratypes. Erigone autw?zna/is Emerton
Figures I 3-1 6
Erigone autumnalis Emerton, 1882: 58.
The male and female types from
Boston, Mass. and New Haven, Conn. are in the Museum of Compara- tive Zoology. Emerton, 1902: 151; 1930: 165; K,eyserling, 1886: 171; Banks, 1895: 87; 1899: 189; 1910: 31; 1911: 447; Crosby, 1905: 314; Bryant, 1908 : 36; Petrunkevitch, 1911: 232; Comstock, 1912: 373 ; 1940: 387; Crosby and Bishop, 1928: 19; Jones, 1936: 70; Kaston, 1938: 180; 1948: 191; Roewer, 1942: 726; Bonnet, 1956: 1757. The group of specimens now considered to belong in Emerton's species were for some time considered to represent four new species. A thorough restudy of the entire lot has now convinced me that they must be regarded as presented here. The appearance of the terminal structures in the male palpal tarsus differs considerably depending upon the way they are viewed and the degree of expansion at the time



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138 Psyche [March
of death. I now have in my collection specimens from the moun- tainous regions of Panama as well as from several locations in the Panama Canal Zone. I also have a male from Trinidad, W. I. and a male from Puerto Rico, W. I. The species has previously been reported from Bermuda and Cuba. The species seems to be the most abundant of any member of the genus from the region under con- sidei-ation. Drawings are offered of specimens from Panama, Trini- dad, W. I. and Puerto Rico, W. I.
Erigone digena sp. nov.
Figures I 7-23
Holotype.
The male holotype is from the Panama Cmal Zone, Gatun, February 27, 1958. The name of the species is an arbitrary combination of letters.
Description. Total length 1.69 mm. Carapace 0.88 rnm long; nearly 0.64 rnm wide; nearly 0.4 mm tall in cephalic region where it is tallest; ~osterior declivity beginning opposite second coxae is somewhat steeper than in E. antegona sp. nov. and E. bereto, sp. nov. Eyes: eight as usual in the genus; viewed from above, posterior row moderately recurved and anterior row more definitely so. Ratio of eyes AME : ALE : PME : PLE = nearly 5 : 6.5 : 6 : 6 (some variation noted among available paratypes) ; lateral eyes somewhat protuberant and PLE somewhat angular. AME separated from one another by about one third of their diameter and from ALE by about their radius. PME separated from one another by about two-thirds of their diameter and from PLE by about the same distance. Laterals contiguous to one another as usual. Height of clypeus nearly equal to eight-thirds of the diameter of AME. Central ocular quadrangle wider behind than in front in ratio of nearly 5 : 4; and about as wide behind as long. Chelicerae: essentially typical of males of the genus; teeth along lateral margin and near the fang groove essen- tially as shown in Figure 17. Promargin of fang groove apparently with four teeth and retromargin with three. Maxillae: with few very small cusps and each with a bristle; otherwise essentially typical of males of the genus. Lip: essentially typical of males of the genus. Sternum: moderately convex; almost as wide just behind first coxae as long; extended between fourth coxae which are separated by about two-thirds of their width.
Legs: 1423 in order of length; tricho-
bothria observed but not placed accurately. Palp : the trochanter has
a ventral tooth; the femur has a series of small cusps on the ven- trolateral surface; the patella has a short apophysis near the distal



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19701 Chickering - Erigone I39
Figs. 17-23.
Erigone digma sp. nov. Fig. 17. Left chelicera of holotype from in front. Fig. 18. Left palpal femur and patella; retrolateral view. Fig. 19. Left palpal tibia and tarsus of holotype; prolateral view. fig. 20. Idem; retrolateral view. Fig. 21. Idem; nearly dorsal view. Fig. 22. Palpal patella, tibia and tarsus of male from Jamaica, W. I.; prolateral vie. Fig. 23. Palpal tibia and tarsus of male from Puerto Rico, W. I.; retrolateral view.




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1 40 Psyche [March
end; the tibia and tarsus seem to be quite distinctive (Figs. 18-23). Abdomen : typical of males of the genus ; without special modifications. Color in alcohol: carapace yellowish brown with cephalic region much darker; chelicei-ae nearly like carapace; sternum dusky gray against a yellowish brown background; legs generally yellowish; ab- domen yellowish in general with the dorsum showing a faintly in- dicated median longitudinal gray stripe and with faintly indicated grayish, narrow, transverse bars; the posterior end is a darker grayish with the venter a varied grayish and yellowish. The color pattern is quite variable among the paratypes available for comparison. Diagnosis.
This appears to be another species closely related to Erigone tamazunchalensis Gertsch and Davis from Mexico but I believe that the rather distinctive features of the palp definitely establish it as a new species.
Records.
In addition to the male holotype, my collection now includes ten males from the Panama Canal Zone as follows: Barro Colorado Island, August, 1950 and July-August, 1954; Summit, Au- gust, 1954 ; Summit Gardens, July, 1954 ; Pedro Miguel, January, 1958; Gatun, February, 1958. A male from Jamaica, Ti-elawney Parish, Glastonbury, November, 1957 and two males from the vicinity of the campus of the University of Puerto Rico at Mayaguez, January 29, 1964 are also placed here following a period during which they were regarded as representing another new species. Erigone dipona sp. nov.
Figures 24-28a
Holotype.
The male holotype is from Boquete, Panama, August 4-1 I, 1954. The name of the species is an arbitrary combination of letters.
Description. Total length 1.17 mm. Carapace 0.6 mm long; nearly 0.49 mm wide; with cephalic region steeply raised where it is nearly 0.33 mrn tall; with a moderately well defined median longi- tudinal thoracic groove. Eyes: eight as usual in two rows; viewed form above, posterior row gently recurved and anterior row more definitely recurved. Ratio of eyes AME : ALE : PME : PLE = 7 : I I : I I : 10. Outlines of eyes very obscure. AME very nar- rowly separated from one another, apparently by somewhat less than their radius; separated from ALE by slightly more than this distance and separated from PME by a little less than their diameter. PME
separated from one another by a little less than two-thirds of their



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Chickering - Erigone
Figs. 24-28a.
Erigone dipona sp. nov, Fig. 24. Left palp of holotype; nearly prolateral view.
Fig. 25. Idem; retrolateral view. Fig. 26. Left palpal tibia; nearly dorsal view, Fig. 27. Eyes of described female para- type; from above. Fig. 28. Epigynum of described female paratype; from below. Fig. 2Sa. Idem; lifted to show posterior surface. Figs. 29-31. Erigone tepena sp. nov. Fig. 29, Right maxilla; posterior surface. Fig. 30. Lefi palpal tibia and tarsus of holotype; prolateral view. Fig. 31. Left
palpal patella, tibia and tarsus of holotype, retrolateral view.



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1 42 Psyche
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diameter and fi-om PLE by nearly their radius. ALE and PLE contigu~us as usual, Height of clypeus nearly equal to three times the diameter of AME. Chelicerae: general shape typical of males oi the genus; a series of teeth along near the lateral sides are, appar- ently, differently arranged on the right and the left; the right cheli- cera has a sesies of three teeth fairly clearly delineated i~ a row7 beIow the cIypea1 mai-gin and probably two or three very minute cusps below those; on the left chelicera there may be three teeth but they are out of line; in place of the usually more or less conspicuous tooth neai- the psomarginal row of teeth along the fang groove appears a group of minute cusps. hlaxillae: typical of =ales of the genus except that teeth appear to be absent. Lip: as usual in the genus. Sternum: convex as usual; about as wide as long; extended between fourth coxae which are separated by a little less than their width. Legs: I 423 in order of length; other features typical of the genus. Palp: trochanter with a small, ventral protuberance; other featui-es essentially as shown in Figures 24-26. Abdomen: typical of males of the genus. Color in alcohol: carapace a light yellowish brown with few dasker sti-eaks and with a moderate amount of Hack pigment in ocular area; sternum a light grayish brown; mouth parts yellowish brown with variations; legs yellowish with some variations; abdomen a light grayish brown dorsally and quite grayish laterally and vm- trally whese there are ,several darker areas and lines especially antei-ior to the genital groove.
Female paratyfle.
Total length I 27 mm. Carapace 0.6 I mm long ; 0.42 n1m wide; about 0.22 mm tall; not as steeply raised in cephalic 1-egion as in male holotype but posterior declivity is quite steep. Eyes: essentially as shown in Figure 27; ratio of eyes AME : ALE : PLIE : PLE = 3 : 5 : 5 : 4.5. ALE somewhat angular. AbIE barely sepal-ated from one another; sepasated from ALE by nearly half their radius and from P3IE by nearly their diameter. PIIE separated from one another by nearly seven-tenths of theii- diameter and from PLE by half their radius. ALE and PLE contiguous as usual. Height of clypeus nearly equal to four times the diametei- of AAIE. Chelicerae: general features typical of females of the genus; fang groove pi-obably with five teeth on each mai-gh fixax- illae and lip: general features typical of females of the genus. Sternum: convex as in male; longer than wide in ratio of about 16
: 13 ; otherwise essentiallj~ as in male. Legs: 1423 in order of length but with only small diflerence in lengths of first and fourth. Spines on palp but no claw observed. Abdo~nen: typical of females



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of the genus; epigj~num somewhat distinctive (Figs. 28-28a). Color in alcohol : carapace, legs and mouth parts yellowish with variations ; sternum light grayish; abdomen yellowish white in general but slightly grayish especially on the venter.
Diagnosis.
This is another species which seems to be closely re- lated to Erigone tamazuncha~e~zsis Gertsch and Davis from illexico but the features of the male palp, chelicerae and eyes establish it as a new species.
Records.
Four paratype male,s and nine paratype females are in the collection and all are from Boquete, Panama, August 4-1 I, 1954. Although there can be no certainty, the resemblance of these females to the holotype male seems to warrant their inclusion in this species. Erigone tepena sp. nov.
Figures 29-31
Holoiype.
The male holotype is from the vicinity of the School of Agriculture, St. Catherine Parish, Jamaica, W. I., Novembei- 23, 195'7. The name of the species is an arbitrary combination of lettm. Description. Total length 2.09 mm. Carapace 0.97 mm long; about 0.77 mm wide; nearly 0.33 mm tall in cephalic region where it is tallest; with a well defined median thoracic groove; no serra- tions observed along ventral margin; general features quite typical of the genus. Eyes: eight in two rows as usual in the genus; seen from above, posterior row ,slightly recurved; anterior row quite def-