Helen R. Coles de Negret and Kent H. Redford.
The Biology of Nine Termite Species (Isoptera: Termitidae) from the Cerrado of Central Brazil.
Psyche 89:81-106, 1982.

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THE BIOLOGY OF NINE TERMITE SPECIES
(ISOPTERA: TERMITIDAE)
FROM THE CERRADO OF CENTRAL BRAZIL
BY HELEN R. COLES DE NEGRET' AND KENT H. REDFORD* The Neotropical region is second to the Ethiopian in numbers of described termite species (Araujo 1970). However, little is known of their biology. The literature on Brazilian termites is largely re- stricted to isolated taxonomic descriptions of species from the Amazon Basin and southern states of Brazil (Araujo 1961, 1969, 1977 and Fontes 1979). Exceptions to this include information re- lating termite species and their distribution to vegetation types in Mato Grosso State (Mathews 1977), the effect of deforestation on termites in the Amazon (Bandeira 1979) and data on the ecology and defense of termites in the cerrado vegetation of the Distrito Federal (Coles 1980).
The present study was done in conjunction with a study on mammalian termite predators, in particular the giant anteater, Myrmecophaga tridactyla (Coles 1980 and Redford in prep.). Six aspects of termite biology of importance in defense by termites against mammalian predators were studied for nine of the most common mound-building termite species in the Distrito Federal, Brazil. Reported here are individual weights, morphology of soldier castes, worker-soldier ratios, mound sizes and forms, mound hard- nesses and nest materials, distributions and abundances of nests and feeding habits for these nine species.
All species studied were from the family Termitidae (see Fig. 1 for comparison of soldier heads), subfamily Apicotermitinae, Grigioter- mes metoecus (Matthews); subfamily Nasutitermitinae, Armitermes 'Laboratoria de Zoologia e Ecologia Animal, Universidade de Brasilia, Brasilia D. F. 809 10, Brazil.
Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138; and Department of Zoological Research, National Zoological Park, Smithsonian Institu- tion, Washington, D.C. 20008.
Manuscript received by the editor March 3, 1982. 8 1




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82 Psyche [vo~. 89
euamignathus (Silvestri), Cornitermes cumulans (Kollar), Cortariter- mes silvestri (Holmgren), Nasutitermes sp., Procornitermes araujoi (Emerson), Syntermes dirus (Burmeister), Velocitermes paucipilis (Mathews); subfamily Termitinae, Orthognathotermes gibberorum (Mathews).
This study was conducted primarily in the Distrito Federal, Brazil (15 47's 47 56'W) with supporting work done in Emas National Park, Goias State (18 19's 52 45'W). Both areas are located within the cerrado sensu latu vegetation type. Cerrado (sensu latu) is a semi-deciduous xeromorphic savanna vegetation found in the inter- mediate rainfall (750-2000mm/yr) area of Brazil. It is characterized by woody plants with thick bark and coreaceous leaves and a sea- sonal ground layer of grasses and herbs. Although geographically and floristically the cerrado vegetation zone is very uniform, physi- onomically it shows considerable variation (Eiten 1972). The types of cerrado sensu latu which were examined in this study are campo limpo (grassland), campo sujo (grassland with shrubs), cerrado sensu strictu (woodland) and cerradzo (dense, tall cerrado). Within the cerrado zone, gallery forest vegetation is found on the wet, more fertile soils along river courses; however this was excluded from the present study as it supports a termite fauna which differs greatly from that of the other vegetation types (Coles 1980). A. Comparative Morphology
Figure 1 depicts soldiers of the eight species of termites examined in this study, with a worker head of the soldierless species Grigio- termes provided for comparison, while Tables 1 and 2 provide information on the fresh weights and total body lengths. Table 2 also provides measurements of mandible length, nasus length, head length, head width and head depth for the soldiers (position of measurements depicted in Figure 2).
As can be seen from these data, the termite species in this study can be placed along a spectrum based on soldier and head shape. The two ends of this spectrum are 'well-developed nasus/vestigial mandibles' (such as Nasutitermes) and 'no nasuslverv well-devel-



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Negret & Redford -
n
Termite Species
Figure 1.
Soldier heads of eight of the species of termites studied; Grigioterme.~ metoecus worker included for comparison: a, Grigiotermes metoecus; b. Arn7iter- mes euamignathus; c, Cornitermes cumulans; d, Corfaritermes .si/\~e.stri; e, Pro- cornitermes araujoi; f, Nasutitermes sp.; g, S~wtermes dims; h, Velocitermes paucipilis; i, Orthognathotermes gibberorurn.



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84 Psyche K^
loped mandibles' (Orthognathotermes). Intermediate posit :Ìö o n: occupied by forms with 'slight nasus development / well-de v e 1 < mandibles' (such as Cornitermes) and 'well-developed nas u s / developed mandibles' (Armitermes). Grigiotermes, with no. s o caste, cannot be placed on this spectrum. These data also show that soldiers with very well- t- o T developed mandibles and poorly developed nasi are both h ez
and longer than soldiers with vestigial mandibles and well-dew ^^- lc nasi, Armitermes once again occupying an intermediate pos ^Ìö-c IS o Complete taxonomic descriptions for Grigiotermes mi e z -4 Arrnitermes euamignathus, Cortaritermes silvestri, Velo c- z-AF e l paucipilis, and Orthognathoterrnes gibberorum can be f o 'ÌàÌÔ n Mathews (1 977). Procornitermes aravjoi is fully described i n E I son (1952). Samples of Cornitermes cumulans collected du xi- nf- study in Brasilia were identified following Emerson ( 1 9 5 =>- though the general head and mandible forms were consist- n -C the published description, head length and width measu re :m were much lower than those previously described for this s pe However. Emerson indicated that there is considerable vari- 'B" Ac mean measurements between colonies from different localit C s -
samples from Brasilia were compared with various other s p e c i g the Museu Zoologia de Universidade de S5o Paulo (MZS F > - most closely related species was C. villosus which was clearly d i ent in that it had a greater number of setae and differently s *z mandibles. As a result of this divergence the best classiå£-i ^z^a appears to be C. cumulans. Specimens from Brasilia have=- I deposited in the MZSP and the Museum of Comparative Z o o la Harvard University.
Samples of Nasutitermes sp. collected from the Distrito F-d were compared extensively with material in the MZSP but c^i- Sf< from all species examined. N. coxipoensis most resembled th< md titermes we studied but differed in being smaller and in h-vir more oval shaped head. Further studies on these two for n s necessary to determine whether these differences are suffic 5 n warrant calling it a new species.
B. Weights
Fresh weights were measured on a Mettler balance. Fifty v^--" o r l and fifty soldiers from each of three different nests were w e % ~3 except for Syntermes for which only fifteen individuals of eat:: h c,



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19821 Negret & Redford - Termite Species 85 from the three nests were weighed and Nasutitermes for which five nests were sampled. The results are presented in Table 1 and are ordered from heaviest soldiers to lightest soldiers. Syntermes dirus has workers and soldiers much heavier than the next heaviest spe- cies, Cornitermes. The termite species with soldiers possessing strong or long mandibles are heavier than those termites whose soldiers have vestigial mandibles, and well developed nasi. These latter soldiers are also lighter than their workers, a relationship reversed in the other termite species.
Table 1.
Individual wet weights of termites (measurements expressed in micro- grams; mean with standard deviation in parentheses). Species Workers Soldiers
Syermes dirus
Cornitermes cumulans
Orthognathotermes gibberorum
Procornitermes araujoi
Grigiotermes metoecus
A rrnitermes euumignathus
Cortaritermes silvestri
Nasutitermes sp.
Velocitermes paucipilis
a Equal number of all three morphs weighed. b Only major soldiers weighed.
c Mixture of two worker types weighed.




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86 Psyche
C. Morphology of Soldiers
The positions of measurements taken on soldier heads are- indi-
cated in Figure 2 (adapted from Coles 1980). Total body lengt: Ai was measured from tip of mandible or nasus, whichever extended further, to the end of the abdomen. The figures presented in T a b l e 2 are the averages of 15 individual soldiers and are ordered from greatest to least mandible length. As can be seen, these five m o rpho- logical measurements are, on the whole, positively correlated- with each other, with total body length and with weight (Table 1 ^> - The major exception is Orthognathotermes, which has mandibles ^a-nd a nasus of a different shape than the other species. D. Worker-Soldier Ratios
Worker-soldier ratios were calculated by counting all o 3? the workers and soldiers in a piece of termite mound. The pieces- was rapidly removed from the surrounding mound so as to prev c n t a change in the normal worker-soldier ratio. For all species exce- pt P. araqjoi, A. euamignathus, S. dirus and C. silvestri, five pie= es of mound from at least three different mounds were counted - The
result obtained from a piece of mound was not used if the piece
contained less than 600 individuals. Because of the large variation obtained in the first five counts for P. araujoi, an additional "ailnree pieces were counted. The fifth count used for A. euamignathu-~t- was an average of 45 samples and was taken from Domingos ( 1 980). Only four counts were taken for C. silvestri. The large diffuse mounds inhabited by S. dirus and the r a p i d retreat of soldiers and workers made it impossible to obtain w o rker- soldier ratios from populations within the mound for this species. Instead, the value presented in Table 3 is an average of counts m a d e on eleven foraging parties. The method used (Coles 1980) w-^a-s to plug the exit at least one hour after foraging had begun. A f t e r spraying with pyrethrin aerosol insecticide all soldiers and wo r k e r s were collected and counted. Table 3 presents the data on wo rker- soldier ratios ordered from greatest to least percent soldiers. Those termite species with soldiers having chemical-based d e~ f en- sive systems have fewer workers per soldier than the other termite species. In fact, for these species, Velocitermes, Nasutitermes and Cortaritermes, there is little variation between species in this worker-soldier ratio. Similarly, Cornitermes and Procornitery-^res,



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19821
Negret & Redford - Termite Species
Figure 2. Positions of morphological measurements of soldier heads: lh= Lat- eral head length; In = nasus length; 1m = mandible length; Wh = maximu m head width; dh= head depth including postmentum.



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88 Psyche [VOI. 89
Table 2. Morphological measurements of soldiers (measurements expressed in millimeters; mean with standard deviation in parenthesis). Lateral
Length Maximum Total
Mandible Nasus of Head Head Body
Species Length Length Head Width Depth Length Orthogna thotermes
gibberorurn
fintermes
dirus
Corniiermes
cumulans
Procorniternies
araujoi
A rmit ermes
euamignathus
Nasut itermes
SP -
Velocitermes
pauc Ipiiis
Cortaritermes
silvestri
Note: Grigiotermes is excluded for it has no soldiers. two similar species have very similar workers-soldier ratios. Armi- termes occupies an intermediate position while Orthognathotermes has a large number of workers per soldier. A. Mound size and form
Table 4 presents data on mean heights, widths and lengths of ten mounds for each of the nine species of termites. Figure 3 (a-r) con- sists of two photographs of each species mound, one of an entire mound and the other of a mound in transverse cross-section. As can be seen from the data and the photographs, the shapes of these mounds range roughly from an inverted cone (Cornitermes) to a low dome (Orthognathotermes).




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19821 Negret & Redford - Termite Species 89 Table 3.
Proportion of workers in nests (mean with standard deviation in parentheses).
Species
Worker- %
Soldier
Soldiers
Velocitermes paucipilis
Nasutitermes sp.
Cortaritermes silvestri
finterms dirus*
Armitermes euamignathus
Procornitermes araujoi
Cornitermes cumulans
Orthognathotermes gibberorurn
*Figures derived from foraging parties. See text, Grigiotermes excluded as it has no soldiers.
The nature and form of individual mounds vary greatly and the characteristics listed below are generalized descriptions of mounds found in the Distrito Federal and Emas Park. Cornitermes cumulans (Fig. 3 a,b): The mound has a very hard outer shell of soil surrounding a soft inner core of carton (fecal material, communited plant material abd bits of soil) which often extends below ground as much as 40 cms. The galleries are large and unlined.
Nasutitermes sp. (Fig. 3 c,d): The mound is domed with the outer several centimeters softer than the inner core (as in arboreal Nasuti- termes and Constrictotermes) and often extends 25cms under- ground. The internal structure consists of thin-walled, convoluted,



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90 Psyche [Vol. 89
Table 4.
Dimensions of the epigeal portion of termite mounds (measurements expressed in centimeters; mean with standard deviation in parentheses). Species Height Length Width
Cornitermes cumulans
Nasutitermes sp.
Velocitermes paucipilis
Grigiotermes metoecus
Procornitermes araujoi 28.8 69.5 60.0
( 12.0) (33.9) (34.4)
A rmitermes euamignathus
Cortartiermes silvestri
Orthognathotermes gibberorurn 15.0 35.9 40.4 (3.0) (1 1.3) (13.6)
irregular galleries with a mottled black and soil-colored lining of fecal origin.
Syntermes dirus (Fig. 3 e,f): This species builds low-domed termi- taria, the major parts of which are below ground level (often to depth of 1.5 m.). The galleries are large and diffuse, often containing grass stores and are lined with regurgitated soil in which individual pellets are clearly visible.
Velocitermes paucipilis (Fig. 4 g,h): The mounds are pyramidal, very soft, crumbly and are generally built around a grass tussock. They often extend several centimeters underground in a series of very diffuse galleries which are lined with a discontinuous layer of black material of fecal origin. Large amounts of cut plant material are found inside the mound.




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19821 Negret & Redford - Termite Species 91 Figure 3.
Mounds of the termite species studied; external view and longitudinal section: a and b, Cornitermes cumuhs; c and d, Nasufirermes sp.; e =nd f, +nierrnes dims.




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92 Psyche [VOI. 89
Grigiotermes metoecus (Fig. 4 i,j): These medium-sized domed mounds are often occupied by other species of termites and ants. The galleries are distinguished by smooth, shiny soil-colored floors and by small pieces of stone incorporated into the 'ceilings.' Indi- vidual deposits of fecal material used in construction are visible on the mound surface.
Procornitermes aragjoi (Fig. 4 k,l): These medium-sized, rounded mounds are often characterized by a thin layer of loose soil covering the outer shell. These mounds are quite brittle and homogenous and have galleries with a mottled lining of black soil and colored parti- cles, probably of fecal origin. They rarely extend below ground. Armitermes euamignathus (Fig. 5 m,n): This species builds very characteristic slightly domed mounds. The walls are very hard but the mound itself is only loosely held to the substratum with a cavity frequently occurring between it and the soil. The internal structure consists of large irregular chambers connected by very small galler- ies. During the alate flight season mounds of this species are charac- terized by earthen turrets several centimeters high built on the outer surface and serving as 'launching platforms' for alates. Cortaritermes silvestri (Fig. 5 o,p): This species builds soft, low rounded mounds with large irregular galleries. The mounds are fre- quently built around grass tussocks and extend several centimeters underground as in Velocitermes.
Orthognathotermes gibberorum (Fig. 5 q,r): The low mounds built by this species are covered with loose soil and bound together by living grass stems. The galleries are regular and homogenous throughout. The mound frequently extends several centimeters underground but can be separated easily from surrounding soil when pried up.
B. Mound hardness and nest material
The 'hardness' of a mound was measured using a soil penetrome- ter which measures the force necessary to push a metal cone into the soil. The resistance to penetration is obtained by dividing the load of penetration (force applied) by the area at the base of the cone, which was 637.939mm3. The resistance to penetration was taken as a measure of hardness of the mound surface. A termite mound is not a solid structure but consists of a complex system of galleries and chambers. The outer wall is often thick enough for penetration of the whole cone. However, at times, the



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19821 Negrer & Redford - Termite Species 93 Figure 4.
Mounds of the termite species studied: external view and Iongitud inai section: g and h. Veloriiermes patiripitis; i and j, Grigioiermes nieIoems; k and I. Prot'orniiermes uruujoi,
cone pushed into a gallery and a low reading was obtained. In o rder to obtain a representative figure for the whole mound ten meas.. ure- ments were taken, each from different positions, e.g. base, m i d dle, top.
The hardness of any mound varies considerably throughout- the
year with the amount of rainfall. To reduce these variations a H the



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94 Psyche [vol. 89
Figure 5. Mounds of the termites species studied; external view and longitudinal section: m and n, Armiierms euamignathus: o and p, CorfariiemexsUvestri; q and r, Orthogna~hoiermes gibbe-rorum.
measurements were made in one month (April) at the end of the rainy season. Some variation in hardness occurs from day-to-day and so on any one day of recording, one mound from each of the eight species was examined. Ten mounds from each species were examined and ten measurements were made from each mound. Care was taken to select approximately the same size of mound for the ten mounds of any one species.
The mean values for the hardness of termite mounds in each species are shown in Table 5. As the range is large (l5.24-O.11 Newtons/mm3) the data were transformed (6) and the differences



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19821 Negret & Redford - Termite Species 95 Table 5.
"Hardness" of outer mound and materials used in mound construction (In column 1, any two means not followed by the same letter are significantly different at p = 0.05. In columns 3 through 6, ++ = usually used; + = occasionally used).
Resistance to
Penetration (Newtons mm')
Nest Construction Material
-
Termite Soil at Regurgitated Fecal
Species Mound Base Soil Soil Material saliva Velocitermes
paucipi1i.s
Nasuritertnes
SP.
Corraritermes
siI\~esrri
Procornitermes
araujoi
Or~hognathotermes
gibberorum *
mermes
dims
Grigiotermes
meioecus
A rn~ilermes
euamignathus
Cornitermes
cumulans
*Determined for only 4 mounds so no statistics performed. between these means tested for significance using Hartley's multiple range test. The ranking obtained from this analysis is shown in Table 5 with the mean values of the raw data. Velociterrnes, Nasuti- termes, Cortaritermes and Procornitermes had the softest nests while Corniterrnes had the hardest nest, 140 times harder than the softest, Velociterrnes.
The composition of material used to build mounds was deter- mined by direct observation of workers. Observations were made on at least ten mounds per species, at different times of the day and year. The results are presented in Table 5. Four types of material



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