Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
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Range
Bolivia and central Brazil (Goias) north to Costa Rica. Costa Rica: Atlantic slope. Range maps (South America) (Costa Rica).
Diagnosis
Sculpture of face composed of alveolae (irregular polygons) to rounded foveae; if foveate, foveae are nearly confluent, intervals between foveae very narrow; face sculpture very shallow, superficial, margins of polygons or foveae not at all elevated; no trace of striae or longitudinal orientation of rugae; HW about 0.9mm.
Additional Description
Clypeus weakly produced, such that in lateral view dorsal margin of torulus is level with profile of clypeus; frontal carina extends obliquely across torulus and joins lateral clypeal carina; eye large (EL/HW about 0.30), shallowly convex; vertex margin well-defined; vertex smooth and shiny with coarse striae radiating perpendicularly from occipital carina, these striae usually short but may extend to vertex margin;
Worker (n=1): HW 0.90, HL 0.90, SL 0.58, EL 0.27, MeL 1.13, MeW 0.64, PrW 0.52, PrL 0.27, PrS 0.21, PrT 0.48, MTL 0.57, MFL 0.66, MFW 0.21, PtL 0.32, PtW 0.29, PpW 0.40, PtH 0.29, AL 1.13, AW 0.96, ASW 0.022.
Face sculpture forms irregular polygons on the type of convexus, a Mato Grosso specimen (LACM ENT 140126), and a series from Brazil, Amazonas, Ilha de Curari (e.g. LACM ENT 140117). Other specimens grade into more foveate sculpture.
Sculpture on AT4 is highly variable (figure). AT4 may be uniformly striate (common condition in material from Central America, Ecuador, Peru, Bolivia). The striae are often underlain by micropunctate sculpture, giving a granular appearance, but the intervals may be nearly smooth and somewhat shining. AT4 may be heavily punctate, with varying degrees of longitudinal orientation of puncta, forming incipient striae (Guyana, Venezuela, central Amazonian material, Mato Grosso specimen - LACM ENT 140126). AT4 may have striae and micropunctate sculpture both nearly effaced, and be nearly smooth and shining (type of convexus; Colombia, Rio Porce - LACM ENT 140127; Brazil, Goias, Jatai - LACM ENT 140158; Brazil, Amazonas, Ilha de Curari - LACM ENT 140117).
The pilosity on AT4 is usually sparse, but one specimen (Mato Grosso - LACM ENT 140126) has dense setae near the postpetiolar insertion, much like belti and hirsutus.
Sculpture on AT5 varies on small spatial scales (e.g., within Costa Rica). AT5 is often uniformly striate, but striae may be effaced medially or entirely.
Images
Worker: lateral view (reduced, original); face view, Costa Rica (reduced, original), Brazil, Mato Grosso (reduced, original); mesosoma, dorsal view (reduced, original); gaster, dorsal view, Costa Rica (reduced, original), Brazil, Mato Grosso (reduced, original), Brazil, Ilha Curari (reduced, original), Guyana (reduced, original).
SEM images of worker: face (reduced, original); head, lateral view (reduced, original); torulus (reduced, original); additional torulus image (reduced, original); gaster (reduced, original).
Natural History
This species has been collected from wet forest areas, typically as workers from low vegetation, canopy, or recent treefalls. One nest series was collected in Venezuela, from a dead twig in a treefall.
Types and Synonymy
Procryptocerus pictipes Emery 1896:98. Holotype (unique syntype) worker: Costa Rica, Suerre, near Jimenez [MCSN]. Kempf 1951:42 (description of nontype worker and queen from Guyana).
Procryptocerus hirsutus race convexus Forel 1901:34. Holotype (unique syntype) worker: Brazil, state of Para (Goeldi) [MHNG]. Proposed NEW SYNONYM.
Procryptocerus hirsutus convexus: Kempf 1951:35.
Procryptocerus striatus scabriusculus var. parva Menozzi 1935:196 (unavailable name). Syntype worker(s): British Guiana, Kuruduni River (Synonymy by Kempf 1951:42).
I examined the holotype of pictipes at MCSN, and of convexus at MHNG, in July, 1990.
Description of convexus type, from museum notes: HW=0.97; sculpture on face like P. belti, but foveae are larger, shallower; pronotum longitudinally striate with an anterior row of foveae; mesonotum like P. hirsutus, longitudinally striate and flat, contrasting with the convex pronotum; propodeal dorsum, posterior face of petiole, and dorsum of postpetiole longitudinally striate; AT4 smooth and shining, with an even, faint areolate pattern, much like the sculpture on the posterior rim of AT4 on P. belti, where the puncta begin to fade; posterior face of forefemur smooth; external face of tibiae weakly rugose; setae on head like P. belti, those on mesosoma, petiole, and postpetiole stiff and longer, about 2x length of those on head; setae on AT4 short, relatively sparse, clustered near the postpetiolar insertion and very sparse on the posterior half, with no underlying pubescence; scapes and foretibiae orange, mesotibiae darker, metatibiae dark brown.
A series of workers collected by J. Adis from Brazil (Amazonas, Ilha de Curari) match the above description exactly.
Phylogenetic and Biogeographic Scenario
The scenario is described as a sequence of events, labeled 1-5 on the figure.
1. belti is closest to an ancestral form that inhabited Central America before the closing of the Panamanian isthmus. Plesiomorphic characters it retains are face sculpture composed of high-sided aroleae (forming a mesh of polygons), clypeus somewhat produced, mesosoma reticulate rugose, AT4 densely punctate, and AT4 densely pilose.
2. At the closing of the isthmus, the belti lineage disperses southward. An associated character change is from reticulate rugose to striate mesosoma.
3. Speciation occurs in South America, producing a new lineage capable of sympatry with the older belti-hirsutus lineage. Synapomorphies associated with this new lineage are much shallower face sculpture (but still a mesh of polygons), and a receding of the clypeus.
4. A subsequent character change is a reduction of pilosity density on AT4. One population known to retain the ancestral pilosity condition is "A" in the figure, from Brazil, Mato Grosso, Sinop. This ancestral condition could have been widespread and subsequently replaced, leaving this relict at the southern periphery of the range. Alternatively, the speciation could have occurred at the southern limit of the belti-hirsutus lineage, and the new lineage spread back northward, evolving apomorphic characters as it went.
5. A subsequent character change is the shallow facial aroleae becoming more foveate, less polygonal. Specimens that retain the ancestral facial sculpture ("B" in the figure) are the type of convexus, and a series from Ilha de Curari, south of Manaus. The derived character state is seen in material from the Amazon River northward to Guyana ("C"), Rio Porce in Colombia ("D"), and Central America and the southern Andes from Ecuador to Bolivia ("E").
AT4 sculpture has changed from punctate to smooth independently in two groups, "B" and "D". In material from the Amazon region north to Guyana, AT4 sculpture is punctate with variable degrees of longitudinal orientation of the puncta. AT4 is distinctly striate on material from Central America and the southern Andes ("E"), with varying degrees of loss of the underlying punctation. "E" could be the most recent wave of the pictipes lineage.
With this hypothesis, belti and hirsutus are not known to be monophyletic. pictipes, defined by the autapomorphies of shallow face sculpture and receding clypeus, is monophyletic. pictipes may contain a nested monophyletic group based on the autapomorphy of more foveate face sculpture. That nested subgroup may contain its own nested monophyletic group based on the autapomorphy of striate AT4.
Material Examined
BOLIVIA: Santa Cruz: 11km NE Aserradero Moira, 14¡29'S, 61¡8'W, 180m, 26 Nov 1993 (P. S. Ward #12163) LACM ENT 140150 [JTLC].
BRAZIL: Amazonas: Rio Taruma Mirim [3¡02'S, 60¡17'W], 22 Mar 1976 (J. Adis) LACM ENT 140133 [LACM]; Ilha de Curari [3¡15'S, 59¡49'W], 1975-1976 (J. Adis) LACM ENT 140117, LACM ENT 140118, LACM ENT 140119, LACM ENT 140120, LACM ENT 140121, LACM ENT 140122, LACM ENT 140123, LACM ENT 140124, LACM ENT 140125 [LACM]; Manaus-K542 [3¡07'S, 60¡2'W], 13-16 May 1991 (F. P. Benton) [CPDC]; Reserva Flor. A. Ducke, Manaus [2¡55'S, 59¡59'W] , 21 Feb 1992 (J. Adis) [CPDC; Manaus [3¡07'S, 60¡02'W], 30 Sep 1987 (Brandao and Diniz) LACM ENT 140154 [MZSP]; Manaus, Tropical Hotel gardens, 8 Jan 1985 (J. C. Trager) LACM ENT 140151 [MZSP]; Bahia: Ubaitaba [14¡18'S, 39¡20'W], 10 Aug 1988 (J. C. S. do Carmo) [CPDC]; F. Bom Jesus, Marau [14¡06'S, 39¡00'W], 12 Apr 1988 (J. C. S. do Carmo) [CPDC]; Fazenda Santa Rita, Ilheus [14¡49'S, 39¡02'W], 12 Sep 1980 (F. P. Benton) [CPDC]; Olivenca, Ilheus [14¡57'S, 39¡01'W], 30 Dec 1992 (J. H. C. Delabie) [CPDC]; Faz. Piedade, Una [15¡18'S, 39¡04'W], 1987 (C. Alves) [CPDC]; Goias: Jatai [17¡53'S, 51¡43'W], Jan 1955 (P. Pereira, M. Carreira) LACM ENT 140158 [MZSP]; Mato Grosso: Sinop, 12¡31'S, 55¡37'W, Oct 1974 (M. Alvarenga) LACM ENT 140126 [MZSP]; Para: Tucurui, Margem esq., 15 Mar 1979 (W. L. Overal) LACM ENT 140134 [LACM]; Transamazonica Km 109, 24 Jul 1988 (A. C. Mendes) [CPDC]; Caldeirao, Rio Itacaiunas, Jul-Aug 1985 (Brandao and Benson) LACM ENT 140152 [MZSP]; Cachoeira do Breu, Oct 1928 (Sampaio) LACM ENT 140156 [MZSP]; Conceicao do Araguaia [8¡14'S, 49¡18'W], 19-25 Jan 1983 (J. A. Rafael) LACM ENT 140157 [MZSP]; Pernambuco: Recife [8¡03'S, 34¡54'W], 1938 (L. Lima Castro) LACM ENT 140153 [MZSP]; Tapera (Pickel) LACM ENT 140155 [MZSP].
COLOMBIA: Antioquia: Rio Porce [7¡28'N, 74¡54'W], 1020m (N. W. Weber) LACM ENT 140127 [MCZC].
COSTA RICA: Alajuela: 11mi N Florencia [10¡31'N, 84¡29'W], 6 Jul 1963 (D. H. Janzen) [USNM]; Heredia: La Selva Biological Station, 10¡26'N, 84¡01'W, 50m, 5 Mar 1993 (ALAS) INBIOCRI001222587, INBIOCRI001231297 [LACM]; same data, 18 Jul 1986 (J. Longino #1398-s) LACM ENT 140141 [JTLC]; same data, 22 Jan 1994 (J. Longino #3518-s) INBIOCRI001282950 [LACM]; Limon: Hitoy Cerere Biol. Reserve, 9¡40'N, 83¡02'W, 100m, 1 Sep 1985 (J. Longino #1007-s) LACM ENT 140142 [JTLC]; Los Diamantes [10¡13'N, 83¡45'W], 7 Apr 1964 (F. S. Truxal) LACM ENT 140137 [LACM]; same data, 12 Apr 1964 (F. S. Truxal) [LACM].
ECUADOR: Guayas: Cerro Blanco, 15km W Guayaquil, 2¡10'S, 80¡02'W, 400m, 13 Aug 1991 (P. S. Ward #11453) LACM ENT 140145, LACM ENT 140146, LACM ENT 140147, LACM ENT 140148, LACM ENT 140149 [JTLC, LACM]; Los Rios, Jauneche, 19km WSW Mocache, 1¡14'S, 79¡40'W, 60, 11 Aug 1991 (P. S. Ward #11437) LACM ENT 140143, LACM ENT 140144 [JTLC, LACM].
GUYANA: New River [3¡23'N, 57¡36'W], 10 Dec 1935 (J. Myers) [MCZC]; Kartabo [Kartabu Point, 6¡23'N, 58¡41'W], Jul-Aug 1920 (W. M. Wheeler) LACM ENT 140128, LACM ENT 140129, LACM ENT 140130, LACM ENT 140131, LACM ENT 140132 [LACM, MCZC]; Demerara River Bank, 1mi from Georgetown [6¡48'N, 58¡10'W], 22 Sep 1918 (H. Morrison) [USNM].
PANAMA: Canal Zone: Pipeline Road, 23 Oct 1975 (G. G. Montgomery and Y. Lubin) LACM ENT 140136 [LACM]; same data, 26 Jul 1976, LACM ENT 140135 [LACM].
PERU: Madre de Dios: Tambopata, 12¡50'S, 69¡20'W, 290m, 1 Mar 1982 (T. L. Erwin) LACM ENT 140138, LACM ENT 140139, LACM ENT 140140 [LACM]; San Martin, Tarapoto, 6¡29'S, 76¡22'W, 350m, 26 Aug 1986 (P. S. Ward #8757) [UCDC].
TRINIDAD: nr. Rio Claro [10¡18'N, 61¡11'W], 1 Jun 1936 (N. W. Weber) [MCZC].
VENEZUELA: no specific locality, 30 Nov 1939 (Anduze) [MCZC]; Bolivar: 49km ENE Tumeremo, 7¡28'N, 61¡06'W, 200m, 10 Aug 1986 (P. S. Ward #8519, #8522) [UCDC].
Literature Cited
Emery, C. 1896. Studi sulle formiche della fauna neotropica. XVII-XXV. Bollettino della Societa Entomologica Italiana 28:33-107.
Forel, A. 1901. Varietes myrmecologiques. Annales de la Societe Entomologique de Belgique 45:334-382.
Kempf, W. W. 1951. A taxonomic study on the ant tribe Cephalotini (Hymenoptera: Formicidae). Revista de Entomologia 22:1-244.
Menozzi, C. 1935. Spedizione del Prof. Nello Beccari nella Guiana Britannica. Hymenoptera-Formicidae. Redia 21:189-203.
Page author:
John T. Longino, The Evergreen State College, Olympia WA 98505 USA. longinoj@evergreen.edu
Date of this version: 7 September 1998.
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