Morphology of the digestive tube of Macuxitermes triceratops and its phylogenetic implications (Isoptera: Termitidae: Nasutitermitinae)

The gross morphology of digestive tube of Macuxitermes triceratops is described and illustrated. The gut of this species is very similar to those of Embiratermes and Ibitermes, and does not show any obvious autopomorphic character. The phylogenetic relations of this genus are discussed based on the available evidence, and it is concluded that it is probably the sister group of Armitermes + Curvitermes + Cryilliotermes.

Secretion of salivary glands of the Brazilian termite Serritermes serrifer Hagen&Bates (Isoptera: Serritermitidae)

The salivary glands of termites are composed of several secretory acini connected by ducts. These glands, in the Brazilian termite Serritermes serrifer, were examined through the electron microscope. The ultrastructure of worker salivary acinus revealed central ductule cells and four different types of cells. Cells of type I contain an abundance of electron-lucid vacuoles of various sizes which fuse to form enormous vacuolar structures that fill up most of the cell. Cells of type II are narrow cells in which the secretion is contained in small clear vacuoles of approximately equal diameter. Both of these cellular types have numerous Golgi bodies and rough endoplasmic reticulum. Type III or parietal cells have an apical plasma membrane deeply infolded and lined by microvilli. This type of cell is located in the acinar periphery and occurs in pairs. Cells of type IV are completely filled with electrondense secretion. The secretory granules can be small in some cells or large and similar to fingerprints in others. This is the first report of the occurrence of these spiral or concentric rings of dense material in the salivary gland of Isoptera.

THE LEG EXOCRINE SYSTEM IN SERRITERMES-SERRIFER (HAGEN, 1858), PHYLOGENETIC IMPLICATIONS (ISOPTERA, SERRITERMITIDAE

The leg exocrine gland was examined in two species of Neotropical termites. Scanning microscopy studies showed a set of pores on the ventral surface of the first and second tarsomeres in all legs of Serritermes serrifer. In Heterotermes tenuis these pores are present on a sunken plate in all castes. To date, this gland has been observed only in Rhinotermitid species. The presence of leg exocrine gland provides additional evidence supporting a close phylogenetic relationship between the Serritermitidae and Rhinotermitidae.

2 PERMANENT LINEAR-CHAINS OF SEX-CHROMOSOMES IN NEOTERMES-FULVESCENS AND KARYOTYPES OF 2 OTHER NEOTROPICAL KALOTERMITIDAE SPECIES (INSECTA, ISOPTERA)

Meiosis and (or) mitosis of males and females of Cryptotermes brevis, Eucryptotermes wheeleri, and Neotermes fulvescens, all of them from the neotropical region, were analyzed. Cryptotermes brevis showed a similar karyotype to that obtained by other authors for specimens of the neartic and Australian regions (2n = 36 for females and 2n = 37 for males, with XX and XYY sex mechanisms, respectively). Eucryptotermes wheeleri, the only species that has been described in this genus, showed the lowest number of chromosomes reported for Isoptera (2n = 22) until now. The male meiosis of this species presents a linear chain of six sex chromosomes, three of them being X and three of them Y chromosomes. Neotermes fulvescens showed a diploid number of 40 for males and 42 for females and, in the first male meiosis, two linear chains of chromosomes, both related to sex. One of the chains, named A, presented nine chromosomes and the other, named B, seven chromosomes. Hypotheses to explain these mechanisms are formulated in this paper and putative ancestral relationships with other species of Kalotermitidae are presented.

Anatomy of the frontal gland and ultramorphology of the frontal tube in the soldier caste of species of Nasutitermitinae (Isoptera, Termitidae)

is a predominant characteristic, conditioned by the presence of castes with different morphology, ontogeny, and development. The soldier caste is unique among social insects and it is responsible for colony defense. Soldiers belonging to the Nasutitermitinae subfamily are very peculiar, since they may be polymorphic and present a nasus in addition to either developed or vestigial mandibles. The defensive secretions of soldiers of the neotropical Nasutitermitinae have been the aim of several chemical studies, but few data exist concerning the anatomy and histology of the exocrine glands. This article presents a comparative study on the anatomy of the frontal gland of soldiers of several Nasutitermitinae species: Syntermes dirus (Burmeister), Syntermes nanus (Constantino), Constrictotermes cyphergaster (Silvestri), Nasutitermes corniger (Motschulsky) and Velocitermes heteropterus (Silvestri), with emphasis on the ultramorphology and ultrastructure of the frontal tube.

Morphology of the head and frontal gland in neotropical Nasutitermitinae (Isoptera, Termitidae)

The Nasutitermitinae species are the most diverse and derived of the Isoptera. The phylogeny of this subfamily has been a point of divergence. In an attempt to solve this problem, we propose the use of the morphological features of the head, frontal gland and its associated muscles as phylogenetic characters in some Nasutitermitinae genera. Results found about the head and frontal gland morphology are discussed and suggested to be used in future systematic studies of termites.

FRONTAL GLAND DEHISCENCE IN THE BRAZILIAN TERMITE SERRITERMES-SERRIFER (ISOPTERA, SERRITERMITIDAE)

The primary function of the soldier caste in the Isoptera is the defense of the termite society. The simplest defense is mechanical with oversized mandibles. Besides the mandibles, some termite soldiers use exocrine glands as a means of chemical defense. These glands produce substances which are toxic and/or repellent to termites enemies. Here we report the only case in the Neotropical fauna of dehiscence of the frontal gland in the soldier caste of the Brazilian termite, Serritermes serrifer (Bates).

Morphology of the nymphoid replacement reproductives in the neotropical termite Armitermes euamignathus (Isoptera, Termitidae, Nasutitermitinae)

Numerous nymphoid reproductives were found in three field nests of Armitermes euamignathus collected in Brazil. We report here a morphological description and a biometric study of these individuals. Nymphoid replacements displayed narrow wing buds when compared with those present in nymphs from the three last instars. Thorax morphology of the nymphoids was similar to the penultimate nymphal instar (N4) or to the ultimate nymphal instar (N5), and their origin from these instars of nymphs is discussed. All the nymphoids had eyes, ocelli, and 15 antennal segments. The nymphoid females from nest 1 had different grades of physogastry and royal fat body. The nymphoid females from nests 2 and 3, the nymphoid males from all nests, and the primary king from nests 2 acid 3 had a common fat body, which is similar to that present in alates. The ovaries and the testes of nymphoids were fully mature and the corpora allata larger than those in imagoes. The mandibular glands were also enlarged in nymphoids but the tergal glands were absent. (C) 1999 Wiley-Liss, Inc.

MORPHOLOGY OF THE SALIVARY-GLAND ACINI IN GRIGIOTERMES-BEQUAERTI (ISOPTERA, TERMITIDAE, APICOTERMITINAE)

The salivary glands of females in Grigiotermes bequaerti (Snyder & Emerson 1949) are composed of many acini. Within the acini, the secretion is collected by canals that join into excretory ducts that open at the acini are formed of 3 classes of cells: secretory, parietal and canalicular. The secretory cells present 2 distinct types which, however, seem to be only different functional stages. Their secretion appears to be highly fluid and accumulates in vacuoles of low electron density. The morphological features of parietal cells point to an ionic transportation function, since they contain an intracellular canaliculus lined with microvilli, and are rich in mitochondria. The final product of the gland may result from the interaction of these 2 cells. The canicular cells located within the acini, in addition to constituting the way of secretion elimination, may have a support function serving as a point of aggregation an interconnection of secretory and parietal cells.

Nymphs in foraging populations of Coptotermes gestroi (Isoptera: Rhinotermitidae)

Food searching activity by subterranean termites involves workers, soldiers and nymphs. The present study was carried out for elucidating aspects of nymph foraging behavior in Brazil where the species Coptotermes gestroi (Wasmann, 1896) is exotic. Monitoring was conducted through making regular collections from seven different colonies for a period of 22 months, which exhibited the production of forager nymphs all year round. A biometric study was conducted to determine the instars of the forager nymphs collected. The identification of male and female nymphs was also conducted for establishing the sex proportion, which was slightly male-biased. From the 533 forager nymphs collected, 34 were from the 3rd instar, 280 from the 4th instar and 219 from 5th instar. The results suggest that 3rd instar nymphs were not too active in the foraging activities because they were collected only in one colony and in an insignificant quantity. (C) Koninklijke Brill NV, Leiden, 2011.

Multiple nymphoid reproductives in the nests of the neotropical termite, Armitermes euamignathus (Isoptera, Termitidae, Nasutitermitinae)

Armitermes euamignathus Silvestri (Termitidae, Nasutitermitinae) is a mound building termite that is common in Brazilian regions of the Cerrado vegetation. Multiple neotenic reproductives were found in three isolated nests of these species localized in other secondary habitats different from Cerrado vegetation. The number of second form queens was always higher than the number of secondary males. In two of these nests, the primary king was present along with the second form reproductives. Eggs and brood were found in the three nests but mature alates were present in only one. Multiple neotenic reproductives were never found in the studied Cerrado region where the nests contained only the primary pair. A study of oviposition rate between primary queens and nymphoid reproductives showed an increased number of eggs in the colony headed by neotenic reproductives.

Secretion of salivary glands of the Brazilian termite Serritermes serrifer Hagen & Bates (Isoptera : Serritermitidae)

The salivary glands of termites are composed of several secretory acini connected by ducts. These glands, in the Brazilian termite Serritermes serrifer, were examined through the electron microscope. The ultrastructure of worker salivary acinus revealed central ductule cells and four different types of cells. Cells of type I contain an abundance of electron-lucid vacuoles of various sizes which fuse to form enormous vacuolar structures that fill up most of the cell. Cells of type II are narrow cells in which the secretion is contained in small clear vacuoles of approximately equal diameter. Both of these cellular types have numerous Golgi bodies and rough endoplasmic reticulum. Type III or parietal cells have an apical plasma membrane deeply infolded and lined by microvilli. This type of cell is located in the acinar periphery and occurs in pairs. Cells of type IV are completely filled with electrondense secretion. The secretory granules can be small in some cells or large and similar to fingerprints in others. This is the first report of the occurrence of these spiral or concentric rings of dense material in the salivary gland of Isoptera.

Key to the soldiers of Atlantitermes Fontes 1979, with a new species from Brazil (Isoptera Termitidae Nasutitermitinae)

A soldier-based key for the identification of the species of the neotropical termite genus Atlantitermes Fontes 1979 is presented. The diagnostic characters for the genus are reviewed and discussed, and the upturned nasus is excluded bacause it is not present in the soldier of every species. A. stercophilus n. sp., from the cerrado vegetation of Minas Gerais, Brazil, is described and illustrated. A. osborni (Emerson 1925) is recorded for the first time in the cerrado vegetation of southeastern Brazil. Drawings of the soldier of A. kirbyi (Snyder 1926) are presented for the first time.

A new species of Constrictotermes from central Brazil with notes on the mandibular glands of workers (Isoptera: Termitidae: Nasutitermitinae)

Constrictotermes rupestris, new species, is described from central Brazil, with illustrations of the imago, soldier, worker head, worker mandibles, worker mandibular gland, and nest. The new species lives in a dry forest, on rocky terrain, building its nest always on rocks. In the colonies examined, all castes showed a striking reddish coloration due to something accumulated in the fat tissues. Inquilinitermes microcerus was present in most examined nests. The worker of C. rupestris has an enlarged mandibular gland. Workers also show an aggressive behavior, which suggests that the mandibular glands may produce defensive secretions.