A new species of ErEymatErmEs Constantino ( Isoptera , Termitidae , Nasutitermitinae ) from the northeastern Atlantic Forest , Brazil

Ereymatermes Constantino is a nasute genus endemic to the Neotropical region, which included Ereymatermes rotundiceps Constantino from the forest of the lower Japurá River, AM, Brazil, and E. panamensis Roisin from the Panama Canal area. Herein Ereymatermes piquira, a new species from the northeastern Atlantic Forest, is described and illustrated based on the soldier and worker castes. The meaning of the two types of workers (“worker with broad gap” and “worker with narrow gap”) and its relation to feeding habits are discussed.

(Syntermes) to a very long tube (Rhynchotermes); and the "true nasute genera", whose soldiers have reduced mandibles and a long frontal tube of variable shape and size, with a small opening.
Despite the great diversity and ecological importance of Nasutitermitinae, the relationships between their lineages are poorly understood, and many systematic problems remain unsolved.For instance, Engel & Krishna (2004) propose to segregate four of the thirteen "mandibulate genera" into a new subfamily, Syntermitinae.Noirot (2001) in their comprehensive comparative anatomy of workers' gut, and by studying a large number of taxa, already affirmed that the "mandibulate" and "true nasute" genera are separated clades.Nevertheless, considering the results of Donovan et al. (2000, Fig. 66), Syntermitinae as proposed by Engel & Krishna (op. cit.) remains polyphyletic.

INTroduCTIoN
Four subfamilies have been recognized within Termitidae (Sands, 1972): Apicotermitinae, Macrotermitinae, Termitinae, and Nasutitermitinae.The monophyly of Termitidae is supported by several synapomorphies but none of their subfamilies are well established, not even in the most comprehensive morphological cladistic analysis of Isoptera based on both neuter castes proposed by Donovan et al. (2000).
Nasutitermitinae has been characterized by having a well-developed frontal gland, which opens at the tip of a more or less developed frontal tube (Sands, 1965).This subfamily include two recognizable groups of genera, the so-called "mandibulate genera", whose soldiers have well-developed mandibles and a frontal tube that may vary from a very short structure barely projecting above the dorsal surface of the head capsule The so-called "small soil-feeding nasutes", recognized within the Neotropical "true nasutes", is a very poorly known group and even the validity of some genera is questionable (Roisin, 1995;Cancello & Noirot, 2003).Nevertheless, Ereymatermes is a relatively well-defined genus, as recognized from the three castes (soldiers, workers and alates).Constantino (1991) described the genus Ereymatermes to accommodate Ereymatermes rotundiceps from the Brazilian Amazonia.This species was collected in a swamp forest at Jaraqui Island, Japurá River, near the county of Maraã, State of Amazonas.Both colonies were found as inquilines of an arboreal nest built by "an undescribed soldierless Apicotermitinae".Later, Roisin (1995) described Ereymatermes panamensis based on three samples collected from the Panama Canal Area, one "from underground chambers" another "from dead wood on forest floor", and the last "from stump of palm tree".
Herein we describe Ereymatermes piquira, new species, collected in the evergreen rain forest, during the development of the project "Richness and diversity of Hymenoptera and Isoptera along a latitudinal gradient in the Mata Atlântica -the eastern Brazilian rain forest" (Cancello et al., 2002), conducted from 2000 to 2005.The termite team, headed by the first author (EMC), has collected many undescribed taxa besides the one described here.

MATErIAl ANd METhods
The examined material, an unique sample from Atlantic Forest at the county of Ilhéus, State of Bahia, Brazil, is deposited in the Isoptera Collection of Museu de Zoologia da Universidade de São Paulo (MZUSP).
Morphometric characters used here follow Roonwal (1970): length of head with nasus (LH, n° 12), length of head to apex of postclypeus (LHp, n° 14, but from profile); width of head (WH, n° 17), height of head excluding postmentum (HH, n° 21), width of pronotum (WP, n° 68), and length of hind tibia (LT, n° 85).The length of the gizzard's first folds was measured as the longest distance between an imaginary line at the base of the columnar belt and the outer margin of the pulvillar belt.All the measurements were taken with an ocular micrometer and are presented in millimeters, under the species description.
The terms "bristles" and "hairs" are used as in Emerson (1925), that is, in a comparative way; "short hairs" are those visible at 12x magnification and "microscopic hairs" are those visible at 50x magnification.Mandibles: Worker with narrow gap (Fig. 2B): left mandible with cutting edge between apical tooth apex and M1+2 apex, concave; posterior margin of M1+2 almost straight; third marginal tooth small but distinct; separated from the molar prominence by a V-shaped gap; molar tooth barely visible at the small gap, apex hidden beneath the molar prominence; some weak ridges on the molar prominence, visible by translucence.Right mandible with a very large apical tooth, a small rounded first marginal tooth and a much smaller second tooth; molar plate smooth; and basal notch weakly develop.

Ereymatermes piquira
Worker with broad gap (Fig. 2A), differs from the "worker with narrow gap" by having at the left mandible an acute angle between apical tooth and M1+2; this last tooth is sharp and larger, with the posterior margin sinuate; a much more conspicuous third marginal tooth; a broader gap between the third tooth and the molar prominence, showing a larger part of the molar tooth; molar tooth larger; at the right mandible the first marginal tooth is more prominent; and the molar plate have four weakly develop ridges, weaker than those of the molar prominence.
Digestive tube (Figs.3A-F; 4A-B): Gut coiling follows the same generic pattern (Constantino, 1991;Roisin, 1995).Gizzard (G) with a complete weakly sclerotized cuticular armature (hexa-lateral symmetry), without ornamentations (spines, scales); pulvillar belt more developed than columnar belt (Fig. 4A).Length of the folds of first order including the pulvillus, measured on one slide, 0.14-0.15.Mixed segment very small.Malpighian tubules attached on the inner face of the midgut ring in two separated pairs on a small nodule at the junction midgut-hindgut, tubules slightly dilated at their bases.Enteric valve (P2) with a conspicuous armature of six equal triangular swellings (hexa-lateral symmetry).Each swelling has a smooth surface and its most distal portion is deflected forward in the gut lumen as a strongly sclerotized shield bearing a row of acute spines (Fig. 4B).Each well-sclerotized swelling is preceded by a bulbous unsclerotized one without spines or with one blunt, short spine.P2 in the same axis of paunch (P3), which is divided in two compartments, P3a and P3b (Fig. 3E).P3b as a conspicuous ring, concealing the foregut in dorsal view.P3 separated from colon (P4) by a conspicuous isthmus.P4a and P4b tubular."U-turn" conspicuously dilated (Fig. 3F).

Comparisons
The soldier of Ereymatermes piquira, n. sp., is distinguished from those of E. panamensis and E. rotundiceps by its smaller size, its narrower and elongate head capsule with a slight constriction in the middle, along with a longer and slender nasus, not upturned in profile.
The workers are very similar to those of the other species of the genus although in the left mandible of the "worker with narrow gap" the third marginal tooth is smaller, the molar tooth is partially visible between the third tooth and the molar prominence, which is smaller than in E. panamensis.In the right mandible the molar plate is smooth, different from that in E. panamensis (Roisin, 1995, fig. 14).The "worker with broad gap" differs from E. rotundiceps by having the posterior margin of M1+2 sinuate, the third marginal tooth more conspicuous, and by lacking the "extra tooth" (Constantino, 1991) between the third tooth and the molar prominence.
The "U-turn", conspicuously dilated in Ereymatermes piquira, n. sp., was also observed in workers of E. rotundiceps deposited at the MZUSP and Fontes (1987b) noticed this character in Cyranotermes.Aside from Angularitermes, all other genera considered "soilfeeder nasutes" of the Neotropical region have a tubular colon.
In Ereymatermes piquira, n. sp., we were not able to observe any variation in worker antennal length as Roisin (1996) did in Subulitermes and Coatitermes.

dIsCussIoN
The so-called "soil-feeding nasutes" group includes species with small individuals, many of them with subterranean habits and poorly known life histories.In fact, their inclusion in a trophic classification as "soil-feeders" is questionable.Cancello & Noirot (2003) discuss this matter, based on the microhabitat where many of these termites have been collected and pointed out that the Neotropical small "soil-feeders" are probably not eating at the end of the humification gradient proposed by Donovan et al. (2001).Although the morphology of the digestive tube of Ereymatermes piquira, n. sp., as well as the previously known species of Ereymatermes shows typical characteristics of soil-feeding termites, the unique sample of this new species was collected in a stand dead trunk, not in the soil.This fact plus the morphology of the worker mandibles indicate that Ereymatermes would better fit in the feeding group III of Donovan's classification (Donovan et al., 2001) while genera such as Angularitermes, Anhangatermes and Cyranotermes would be included in group IV as strict soil-feeders.Roisin's (1996) observations on Coatitermes and Subulitermes strongly suggested that the two morphs of workers represent successive instars, being the "narrow gap" the first instar and the "broad gap" the second instar worker.This morphological differentiation does not correspond to sexual dimorphism and both sexes are present among neuters.Cancello & Noirot (2003), in agreement with Roisin (op. cit.), considered that in all the "strict soil-feedings" species for which the caste development has been studied there is a simplified polymorphism, with only one monomorphic worker instar (reviewed in Roisin, 2000).

ACkNowlEdgEMENT
We are grateful to Dr. Charles Noirot for his kind agreement to study a termite worker sent by us, and by confirming our first thought on the identity of the material herein described.We also thank Yana Teixeira Reis, who collected the specimens, and two anonymous referees for their useful comments and suggestions on the manuscript.This work was partially supported by the State of São Paulo Research Foundation (FAPESP) within the BIOTA/FAPESP -The Biodiversity comments Virtual Institute Program (www.biotasp.org.br),Proc.98/05083-0.

rEFErENCEs
Worker (Figs.1C, D): Dimorphic.Worker with narrow gap, most frequent than those of broad gap.Both types of workers have the head capsule rounded with the fontanelle region slightly depressed; postclypeus moderately inflated; antenna with 13 articles.Pronotum shallowly saddle-shaped.Tibial spurs 2:2:2.Head capsule with some erect bristles and numerous hairs of different size and orientation over the entire surface.Postclypeus with two stout erect bristles and several hairs on anterior margin; labrum with at least six bristles.Pronotum with bristles on both margins.Measurements of six workers with narrow gap from type-colony are given as range, values for the unique worker with broad gap in parentheses: WH: 0.64-0.69(0.69); LT: 0.57-0.61(0.57); left mandible index: 1.5 (1.4).

FIgurE 1 :FIgurE 2 :
FIgurE 1: Ereymatermes piquira, n. sp.Soldier, Holotype: A, head in dorsal view; B, head and pronotum in profile.Worker: C, head in dorsal view; D, head in profile.Scale bar in millimeters.

FIgurE 4 :
FIgurE 4: Ereymatermes piquira, n. sp.A, Worker gizzard armature.I to III, columnar folds of first, second and third order respectively; p1-p2, pulvilli of first and second order.B, Worker enteric valve armature: short spines of the bulbous unsclerotized swellings remarked by arrows.

Cancello & Cuezzo, new species
Paratypes: soldiers and workers of lot nr 11292 (MZUSP) with the same data as the holotype.Imago: unknown.Soldier (Figs.1A, B): Head capsule oval, in dorsal view, with a slight constriction behind the base of antennae, at the middle of the head considered from the base of the nasus till the rear margin of the head capsule.Dorsal margin of head straight or with a slight depression in the middle, in profile.Long cylindrical nasus, not upturned in profile.Labrum very reduced.Top of head with four bristles at the base of nasus and some scattered ones, plus hairs of different size and orientation, and microscopic hairs denser at the base of nasus.Nasus covered with dense microscopic hairs, becoming longer and conspicuous toward the apex.white; digestive tube visible through abdominal sclerites.Measurements of five soldiers from type-colony are given as range, values for holotype in parentheses: LH: 1.32-1.38(1.38); LHp: 0.82-0.84(0.84); WH: 0.64-0.66(0.66); HH: 0.44-0.46(0.44); WP: 0.38-0.40(0.38); LT: 0.66-0.70(0.66).