W. L. Brown, Jr.
The Neotropical Species of the Ant Genus Strumigenys Fr. Smith: Group of gundlachi (Rogers).
Psyche 66:38-54, 1959.

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THE NEOTROPICAL SPECIES OF THE ANT GENUS STRUMIGENYS FR. SMITH:
GROUP OF GUNDLACHI (R0GER)l
BY WILLIAM L. BROWN, JR.
Museum of Comparative Zoology, Harvard University This paper is a continuation of my series on the New World fauna of the dacetine ant genus Strumigenys Fr. Smith. Earlier parts, con- taining keys to the abbreviations for measurements and proportions, may be found in Jour. New York Ent. Soc. 61 : 53-59, 101-no (1953). In addition to these, other parts have been published or are being prepared. At the end of the series, an illustrated key to the New World members of the genus will be forthcoming. Relationships of the gundlachi Group
The present section deals with a group approximately equivalent to what I called in my preliminary generic revision of the Dacetini (Brown, 1948, Trans. Amer. Ent. Soc., 74: 101-129) by the name Strumigmys subgenus Pyramica. At that time, the group seemed rather distinct from all the other Strumigenys species on the basis of the following characters :
I. Mandibular insertions more remote.
2. Apical fork of mandible with more or less reduced teeth. 3. Inner mandibular border with a series of three or more denticles, instead of two, one or no preapical teeth in Strumigenys s. str. 4. Antenna1 scapes shorter and broader.
5. Spongiform appendages of petiole and postpetiole reduced. 6. Labral lobes longer.
7. General habitus, especially head shape. Since 1948, I have had the opportunity to study carefully the three species recently described by Kempf (1958, Rev. Brasil. Ent., 8: 59- 68) as the S. connectens group, which bridges very nicely the gap between Pyramica and the more typical Strumigenys - in particular, the S. Iwisime group. The steps from Strumigenys to Pyramica are so gradual that it is clear only an arbitrary distinction can now be drawn between the two groups. Under these circumstances, there is no need for a formal generic or subgeneric split, and the name Pyraniica goes into the synonymy of Strumigenys. (The one other 'Published with the aid of a grant from the Museum of Comparative Zoolo- gy at Harvard College.
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38 Psyche
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subgenus of Strumigenys is Labidogenys Roger, which also deserves synonymy from present evidence.) In the present paper, 'rgundlachi group" is used, instead of Pyramica, to include the species gundlachi (Roger), eggersi Emery, subedentata llayr, denticulata Mayr, jamaicensis Brown and trieces n. sp. It should be emphasized, how- ever, that the group is arbitrarily limited, and that S. connectens and its relatives could as well be included as not. The Identity of Pyramica gundlachi Roger Roger described Pyramica yundlachi in 1862, only two years after Frederick Smith had established Strumigenys. Roger based his species on worker and female specimens from Cuba. Roger himself quickly ( 1863) recognized that p/ndlachi was so close to Strumigenys that Pyramica would have to fall as a synonym of that genus. In 1890, Emery demonstrated that gundlachi was a composite species; the female was then named as Strumigenys rogeri Emery, a distinct species we now know to have been introduced into Cuba from Africa.
In the meantime Mayr ( I 887) had recharacterized gu~ndlachi from a cotype worker that Roger had sent him earlier. Both Roger and Mayr described gundlachi as having the inner mandibular border unarmed before the apex and as having the ventral apical tooth divided. The remainder of the information available indicated to me that yundlachi, despite these characters and despite the fact that subsequent authors had described varieties in this complex as having unarmed preapical masticatory borders, belonged with a group including eggersi, denticulata and subede,ntata and their var- ieties and synonyms. Accordingly (without then knowing the con- necks group) I revived Pyramica as a subgenus with gundlachi as the (monobasic) type species (Brown, 1948). From 1887 until 1948, the true gundlachi was ignored by most authors, and its identity wrongly guessed by several others. Finally, through the kindness of the late Prof. Bruno Pittioni of the Vienna Museum, I was able to examine the critical syntype worker that Roger had sent to Mayr. The mandibles of this specimen turned out to be encrusted with ancient glue, and, since this was the only speci- men in Mayr's collection, it seems clear that he merely followed Roger in describing the mandibles. The glue was carefully removed with Barber's fluid, revealing that the mandibles have a full comple- ment of preapical denticles and a normal apical fork with two minute intercalary denticles. In short, the gundlachi syntype was found to be



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19591 Brown -Ant genus Strunzigenys 39
identical with types of 8. eggersi infuscata Weber and with many other samples from the Caribbean area in the MCZ. It became evident that most of the forms originally described as varieties of S. eggers'i were in fact only variants of gundlachi. Later, Dr. E. M. Hering, of the Zoologisches Museum in Berlin, kindly confirmed the same points for the remaining gundlachi syntypes in the Roger Col- lection.
Relationship and Synonymy of S. gundlachi and 8. eggersi Early in the study, S. denticulata and S. subedentata (with its synonyms clavata and tristani) were recognized as distinct species. Later, the new species jamaicensis and trieces were discovered and set to one side. The large residue of samples available in the gund- lachi group all appeared to fall into one complex of very similar but variable forms. On further study, this complex was resolved into two morphological species, one corresponding to the gundlachi type, and the other to syntypes of eggersi in the USNM, differentiated by the characters cited in the description below and shown in Figs. 7 and 8. There remained the task of determining the identity of the six subspecies and varieties assigned to eggersi by various authors: var. vincentensis Forel, var. cubaensis Mann, var. banillcnsis Santschi, var. isthmica Santschi, subsp. infuscata Weber and var. berlesei Weber. Of these, vincentensis, cubaensis and baniZlensis were all de- scribed as lacking preapical denticulation on the mandibles. The types of cubaensis were examined first; these are specimens of Strumigenys Zouisianae Roger, and have been synonymized accordingly (Brown, 1953, Amer. Midi. Nat., 50: 28-29.). A worker type of banillensis from the Santschi Collection proved to have partly broken but dis- tinct preapical denticulation, and it agreed well otherwise with gundlachi. The unique type of vincentensis cannot be found in the British Museum or in the Forel Collection; it is almost certainly just another gundlachi specimen in which the denticulae were over- looked, judging from the description and locality. Types of in- fuscata and berlesei were compared with the gundlachi lectotype, and these names are judged to be straight synonyms. The description of isthmica agrees well with the types and Panamanian samples of gundlachi. All named variants of eqqersi are thus accounted for. There is one more name: S. bierigi Santsihi. The description of this form from Cuba fits the typical gmdlachi so well that there seems no reason to doubt its synonymy; gundlachi is the most common



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40 Psyche [September
species of the group so far found on Cuba. The status of the names involved is summarized in list form:
Group of S. gundlachi
gundZachi (Roger
-
-eggersi var. vincentensis Forel n. syn. -
-eggersi var. banillensis Santschi n. syn. zbierigi Santschi n. syn.
=eg.gersi var. isthmica Santschi n. syn. zeggersi subsp. infuscata Weber n. syn.
-
-eggersi var. berlesei Weber n. syn.
eggersi Emery
denticulata Mayr
subedentata Mays
~tristani Menozzi n. syn.
~rlavata Weber n. syn.
jmnaicensis Brown
trieces n. sp.
Strumigenys gmdlachi ( Roger)
(Figures I, j)
Pyramica gundlachi Roger, 1862: 253. pi. I, fig. 18a, worker nec female. Type loc.: Cuba. Lectotype, by present designation, the worker specimen in Naturhistorisches Museum, Vienna. Other syntypes in Zoologisches Mu- seum der Humboldt Universiiat, Berlin.
Lectotype examined.
Strumigenys gundlachi, Roger, 1863, Verz. Formic., p. 40. Mayr, 1887: 570, worker.
Strumigenys eggersi var. vincentensis Forel, 1893, Trans. Soc. E'nt. London, p. 378, worker. Type loc.: Forest near chateaubelake, 1000 feet, St. Vin- cent, B. W. I. Location of type unknown, presumed lost. New synonymy. Strumigenys eggersi var. banillensis Santschi, 1930: 80, worker. Type loc.: Sierra Banilla, near Habana, Cuba Unique holotype in Santschi Coll., Basel; examined. New synonymy.
Strumigenys bierigi Santschi, 1930 : 80, worker. Type Iocs.: (1) Marianao, Cuba; (2) La Habana, Cuba. Types in Santschi Coll., Basel; not seen. Santschi, 1931 : 276, worker variation. New synonymy. Strumigenys (Strumigenys) eggersi var. isthmica Santschi, 1931 : 276, worker. Type loc.: France Field, Panama. Syntypes in Santschi Coll., Basel. New synonymy.
Strumigenys (s. sir.) eggersi subsp. infuscata Weber, 1934: 35, worker, fe- male. Type loc.: Limones Seboruco, Soledad, Cuba. Syntypes in MCZ, Coll. Weber. New synonymy.
Strumigenys (s. str.) eggersi var. berlesei Weber, 1934: 36, female. Type loc.: Harvard Botanical Gardens, Soledad, Cuba. Holotype in Coll. Weber, examined. New synonymy.
Nec Strumigenys gundlachi of Creighton (1930, Psyche, 38: 179, fig. 1 A), which is based upon a worker from what later became the type series of S. caribbea Weber. S. caribbea was formally synonymized with S. silvestrii Emery by Brown, 1959, Stud. Ent. (n. s.), 2: 25.



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19591 Brown -Ant genus Strumigenys 4 1
Worker: TL 1.7-2.1, HL 0.40-0.49, ML 0.24-0.32, WL 0.40- 0.50 mm. CI 79-86, MI 59-66.
This variable species is small and rather slender, with convex head and alitrunk, the latter with a weak but readily discernible metanotal groove and acute, oblique propodeal teeth with concave, cariniform infradental lamellae. Mandibles straight, inner borders straight to weakly convex, with 4-9 preapical denticles along the apical half or more, which are very variable in size, shape and spacing in different samples, and are often very difficult to see except in dark silhouette against a bright background. The three most distal teeth are often larger than the rest, but sometimes all of them are extremely small. The dorsal tooth of the apical fork is short, but is longer than its ventral mate; between them are two minute intercalary denticles. Petiole and postpetiole shown in Figure 5; note the small but still distinct spongiform appendages.
Body generally densely reticulate-punctulate, opaque, although in some examples the lower posterior sides of the alitrunk may have the sculpture partly effaced and shining. Gaster smooth and shining when clean, with distinct spaced longitudinal carinae taking up about the basal quarter or so of the first segment. Sometimes faint traces of shagreened sculpture also occur on the basal half of the gastric tergum, and some specimens are fouled with dirt or hardened secre- tion, so that it becomes difficult to tell them from eggersi workers in this respect.
Ground pilosity of head and promesonoturn consisting of slender, curved, decumbent, linear-spatulate hairs, numerous on head but sparse on promesonotum. Fringing hairs of head shown in Figure I. Mandibles with fine subappressed pointed hairs, and a row of short oblique pointed hairs along each inner mandibular border. Longer erect hairs are mostly slender, truncate to feebly remiform or clavate: one pair on vertex, one pair on occiput, one or two pairs on petiolar node, two or three pairs on postpetiole, and 30-45 hairs on gastric dorsum, arranged more or less in transverse rows. I,n addition, there are bilaterally paired erect hairs which may be either long and flagel- liform or short and paddle-shaped (remiform). Apparently, remiform hairs are readily transformed into flagelliform ones by the detachment of the rim of the hair at one side, so that the hair frays out to a long, slender point. Flagelliform hairs are often seen reflexed or looped, like a furled coachwhip, and it is difficult to distinguish such hairs from the remiform ones. One of these hairs is to be found on each lateral occipital convexity (Figure I), and there is a pair on the



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42 Psyche
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Figures 1-4. Strumigenys of the gundlachi group, heads of workers, right antenna omitted; only the fringing pilosity is shown, and mandibular hairs are omitted. Figure 1, S. gundlachi (syntype of the synonymous S. eggersi infuscata from Cuba). Figure 2, 5. eggersi from S. Teresa, Espiritu Santo, Brazil. Figure 3. S. denticulata from Trinidad. Figure 4. S. jamaicensis, paratype. Drawn to same scale.




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Brown -Ant genus Strumigenys
Figures 5-9. Strumigenys of the gundlachi group. Figure 5, S. gundlachi, side view of pedicel to show spongiform appendages; same specimen as Figure 1. Figure 6, S. eggersi, side view of pedicel, same specimen as Figure 2.
Figure 7, 5. subedentata male, volsella of genitalia, Mixco, Guatemala. Figure 8, Strumigenys trieces, new species, holotype worker. Figure 9, A'. subedentata, worker from Panama Canal Zone. Figures 5, 6, 8 and 9 are drawn to the same scale as Figures 1-4; Figures 8 and 9 carry the same conditions as 1-4.




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44 [September
humeri and a pair on the mesonotunl. The pilosity varies in different samples, however, and specimens are frequently partly denuded. Color usually medium ferruginous, but some samples are much darker; a Jamaican series is blackish-brown. The female is similar to the larger workers of the same nest series, apart from the usual caste differences, but the head averages a trifle broader (CI 83-89), and the gastric dorsum is more or less distinctly shagreened over the basal segment, but usually not so strongly sculp- tured as is the eqgersi female. Male unknown. Distribution : Occurs widely in countries bordering the Caribbean ; actually reported from southern Mexico, Costa Rica and Panama; Central America may be the original home of the species. It is well
established in Trinidad and Tobago, Cuba and Jamaica, and southern Florida, doubtless after introduction through human commerce, at least in some of these places, but it has not been found on the South American mainland.
Localities for material examined : Trinidad : Laboratory at Simla, 800 feet, 4 miles north of Arima (R. Foster leg.). Arima-Blanchi- seusse Road (N. A. Weber leg.). Arima (Weber leg.). Macqueripe Bay ( Weber leg.) . St. Augustine ( Weber leg.) . Tobago Island : (R. Foster leg.). Jamaica : near Round Hill, Manchester Parish (H. B. Mills leg.). Southfield and Black River, St. Elizabeth Parish (Mills leg.). Cuba: various collections in and near Soledad, Las Villas Prov. (leg. M. Bates and G. Fairchild, E. 0. Wilson, N. A. Weber) , including types of infuscata and 'berlesei. Mina Carlota,
Trinidad Mts. (Wilson leg.). Baragua, Camaguey (Bates and Fairchild leg.). Florida, U. S. A. : Royal Palm Ranger Station, Everglades National Park (L. J. Stannard leg.). Northern Key Largo (E. 0. Wilson leg.). Mexico : Pueblo Nuevo, near Tetzonapa, Veracruz (Wilson leg.). Villa Hermosa, Tabasco (F. Bonet leg.). Finca el Real, Ocosingo Valley, Chiapas (Goodnights and Stannard leg.). Costa Rica: without further locality (leg. H. Schmidt, F. Nevermann). Panama Canal Zone: Barro Colorado Island, many collections by J. Zetek, E. S. McCluskey, W. L. Brown, Jr., and others.
Biology: E. 0. Wilson (unpubl. notes) kept a colony of gmdlachi for over a month in Cuba, during which time it captured and con- sumed entomobryoid and sminthurid collembolans, but ignored podu- roids, a small cricket nymph, various mites and minute millipeds. Hunting is usually of the relatively immobile ambush type, which is to say that the ants approach the prey and, when close enough to de-



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19 591 Brown -Ant genus Str,umigenys 45
tect its position, freeze with mandibles held open toward it (at an angle of 60å¡-70 in this case). However, sometimes workers ap- proach the prey and strike quickly and directly, without waiting. If prey is struck and continues to struggle, it is lifted off the ground and stung in the usual manner of Strumige-nys. McCluskey and I found this species in nearly every berlesate of upper soil and leaf litter that we examined on Barro Colorado Island; it is evidently there the most common dacetine species and one of the more frequent ant species of the forest floor. Wilson found gundlachi to be somewhat less abundant in Veracruz. Although it is abundant in tropical rain forest, it also lives in second-growth forest, thickets, and cacao plantations. Weber ( 1952) took a sample deep in a cave on Trinidad among manure and debris from the oil-birds (Steatornis) and bats living there.
Strumigenys jamaicensis Brown
(Figure 4)
Struimqenys jamaicensb Brown, 1959, Brev. Mus. Comp. Zool., 108: 6, work- er. Type loc.: Corn Puss Gap, 2000 ft., St. Thomas Parish, Jamaica. Holo- type in Coll. Illinois State Natural History Survey, Urbana, Illinois; paratypes in MCZ.
Worker: TL 2.3-2.6, HL 0.52-0.56, ML 0.40-0.42, WL 0.55-0.57 mm. CI 81-82, MI 75-77.
Resembles S. gz~ndlachi, but larger and with relatively much longer mandibles and antennae, particularly the scapes. Mandibles with gently convex outer borders and straight inner borders bearing 6-8 strong, acute denticles which occupy about the distal 2/3 of the border. Body in general relatively more slender than in yundlachi. Sculpture, pilosity and spongiform appendages as in gundlachi, al- though in jamaicensis the ground pilosity tends to be less conspicuous and the erect hairs larger; also, the gastric hairs are larger and fewer. Color blackish-brown. Female and male unknown. In addition to the holotype nest series from Corn Puss Gap, I studied two additional (paratype) series from Hardwar Gap (about 4000 feet), Portland Parish, Jamaica. All of the specimens were taken by H. B. Mills by Berlese funnel from soil-leaf litter charges. Distribution and relationships: So far as is known, this species is confined to the mountains of Jamaica. It appears to be a, specialized descendant of an early immigrant population derived from the main- land gundlachi stock. Both gundlachi and eggersi now also occur on Jamaica, probably as a result of accidental introduction by man, but



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46 Psyche [September
there is no evidence of intergradation between jamaicensis and either -
of these species.
Strwnigenys eggersi Emery
(Figures 2, 6)
Strumigenys eggers'i Emery, 1890: 69, pi. 7, fig. 9, worker, female. Type
loc.: St. Thomas, West Indies. Syntypes in Museo Civico di Storia Naturale, Geneva, and in USNM, several examined.
Strumiqenys (Strumigenys) eqgersi, Santschi, 1931: 276 (records from Pinar del Rio Prov., Cuba, and key to "varieties."). Worker: TL 1.6-2.0, HL 0.39-0.47, ML 0.22-0.27, WL 0.39- 0.46 mm. CI 83-88, MI 56-64. Very similar to S. gundlachi, averag- ing a little smaller, with relatively shorter mandibles, although di- mensions and proportions of the two species overlap broadly. Mandi- bles straight, with weakly convex inner borders, each bearing 4-8 minute denticles on its distal 1/3 to 1/2. Color yellowish ferrugin- ous, lighter than usual for gundlachi. The two chief characters are these :
I. Spongiform appendages of petiole and postpetiole obsolete, the lateral postpetiolar lobes represented by a narrow lamellate margin (Figure 6).
2. First gastric tergum superficially reticulate-punctulate and opaque in front, becoming indefinitely shagreened and weakly shining behind.
The female differs from the workers in the same way that the gundZachi queen differs from its workers. Reticulate sculpture of gastric dorsum more distinct and more opaque than in worker. Male
unknown.
Distribution: The home range is probably southern Brazil and Bolivia, though lack of collections from central and northern Brazil prevents us from knowing how far north this species extends. S.
eggersi is also known
from widely scattered localities in the West Indies, Florida and southern Mexico, sometimes sympatrically or nearly so with 5. gz~ndlachi, and it seems likely that it has been in- troduced by man at these points.
Localities for material examined: Bolivia: Espia Rio Bopi (W. M. Mann leg.). Brazil: Agudos, S. Paulo State (W. W. Kempf and C. Gilbert leg.). Rio de Janeiro (T. Bosgmeier leg.). Santa Teresa, Espiritu Santo State (0. Conde leg.). West Indies: Trinidad (P. B. Whelpley leg.). Pitch Lake and Trinity Hills Forest Reserve, Trinidad (N. A. Weber leg.). Roseau, Dominica (Weber leg.). St. Thomas ( Baron Eggers leg.), syntypes of eggersi, in USNM. Maya-



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19591 Brown -.Ant genus Strumigenys 4 7
guez, Puerto Rico (M. R. Smith leg.). Petit Goave and Fond Verrettes-Refuge, Haiti (H. B. Mills leg. ) . Jamaica : Spanish Town, St. Catherine Parish; Mt. Diablo, St. Ann Parish; Black River, St. Elizabeth Parish; Heron's Hill, Manchester Parish (all Mills leg.). Soledad, Las Villas Prov., and San Vicente, Pinar del Rio Prov., Cuba (E. 0. Wilson leg.). Florida, U. S. A: Fisher's Island (J. E. Porter leg.). Archbold
Biological Station, Highlands County ( H. S. Dybas leg.). Mexico : Palmillas, Tabasco (F. Bonet leg.) . Chi-
chen Itza, Yucatan (L. ]. Stannard leg. ). Biology: Weber found specimens in a compost heap in the Botani- cal Garden at Roseau, Dominica, and in an island of vegetation grow- ing in the Pitch Lake of Trinidad; also on Trhidad, he took a sample from low-growing epiphytes in second-growth forest. Kempf sifted specimens from humus in SZo Paulo. Indications are that this species can stand more dryness than many dacetines, and its presence in many culture areas suggests that it is spreading rapidly through nursery stock transport and other human commerce. The Floridian records for both this species and gundlachi are the first for the continental United States.
Struviigenys denticulata Mays
(Figure 3)
Strumigenys denticulata
Mayr, 1887 : 576, worker. Type loc.: Blumenau, S. Catarina State, Brazil. Types in Naturhistorisches Museum, Vienna, and in MCZ; two workers examined. Emery, 1890: pi. 7, fig. 8, worker. Worker: TL 1.8-2.2, HL 0.42-0.48, ML 0.31-0.39, WL 0.42- 0.49 mrn.
CI 77-80, MI 74-83. Similar to gundZachi and eggersi, but more slender, and with very long, slender, slightly bowed man- dibles, each bearing 5-9 denticles along the distal half 01- more of their inner borders. The antennae are also proportionately long and slender. Spongiform appendages obsolete, like those of eggersi. Sculp- ture as in eggersi, except that the gaster is predominantly smooth and shining, with only a weak basal shagreened band. Color yellowish-
ferruginous to medium ferruginous.
Female with stronger and more extensive reticulation on gaster, covering nearly the entire dorsum of the first segment. Distribution: Known from widely scattered localities in South America, reaching from northern Argentina to the Guianas and Trinidad. It probably ranges through much of central Brazil, whence no collections of ants are available from Berlese samples. Localities for material examined : Argentina : Ing. Juarez, Formosa Prov. (N. Kusnezov leg.). Brazil: Blumenau, S. Catarina State



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48 Psyche [September
(Hetschko leg.), syntypes of denticulata in 3ICZ. Itapecirica, S. Paulo State (Kempf and Santos leg.). Agudos, S. Paulo State (C. Gilbert, W. W. Kempf leg.), several series. Belem, Para State (C. R. Gonqalves). British Guiana: Kartabo Point, and Forest Settle- ment on the Mazaruni River (N. A. Weber leg.). Trinidad: Trin- ity Hills Forest Reserve (Weber leg.).
Biology: According to Weber ( 1952), this species occurs in both primary forest and second-growth, in leaf litter or in rotten twigs of low epiphytes. Kempf (1958) took it in humus, and Wasmann ( 191 5) reports a sample taken in a nest of Anoplotermes in south- eastern Brazil.