CAMPONOTVS (KARA VAIEVIA) TEXENS SP. N. AND C. (K.) GOMBAKI SP. N. FROM MALAYSIA IN COMPARISON WITH THE OTHER KARAVAIEVIA SPECIES (FORMICIDAE: FORMICINAE)*

The two colonies of Camponotus texens were found by U. Maschwitz: one of the Gombak Valley, about 27 km north of Kuala Lumpur, and the other one in the region of Kuantan, on the east coast of Malaysia. Of C. gombaki, only one colony was discovered in the Gombak Valley. Twenty workers of each of the colonies were used for the descriptions that follow. The description of the sexuals for C. texens was based on 5 males from the colony of Kuantan and 5 females from the Gombak Valley. Only 5 females, but no males, were available for C. gombaki. One worker of Camponotus (Karavaievia) overbecki was made available to the author by Dr. Baroni Urbani from the Santschi Collection in Base1 (Switzerland). Three workers of this species were used for classifiction from the Fore1 Collection in Geneva (Switzerland) along with three workers and two dealate females of Camponotus (Karavaievia) exsectus from the Emery Collection in Genoa (Italy). However, specimens of C. (Karavaievia) dolichoderoides were not available from either the Fore1 or Emery Collections.


rsycne
[VOL 92 The examinations of C. texens, C. gombaki and C. overbecki were made with the aid of a binocular microscope; the measurements of the animals were made at a magnification of 65X.Scanning electron micrographs of C. texens and C. gombaki, presented as part of this article, were taken by a Hitachi S 500.
The following abbreviations are used below (measurements as in Bolton, 1977): TL: total length.The total outstretched length of the individual from the mandibular apex to the gastral apex.HL: head length.The straight-line distance between the anterior clypeal margin and the mid-point of the occipital margin in full-face view.CI: cephalic index = (H W X loo)/ H L SL: scapus length.The straight-line length of the antenna1 scape excluding the radicle.SI: scapus index = (H W X loo)/ SL PW: pronotal width.The maximum width of the pronoturn in dorsal view.OD: ocular diameter.The maximum width of the eyes.All measurements are expressed in millimeters.
The critical reading of the manuscript by Dr. C .Baroni Urbani and Dr. P. van Voris is gratefully acknowledged.

RESULTS AND DISCUSSION
Characteristics of the Subgenus Karavaievia Emery 1925 The description of the subgenus Karavaievia follows that of Emery (1925).This description is mainly a listing of characters which are partly superficial but which serve to distinguish this subgenus from all the others (Emery, 1925).A thorough diagnosis of 'Karavaievia' would require a revision of the whole genus Camponotus, which is urgently needed but which is not the intention of this paper.Thus, the subgenus Karavaievia is in a preliminary state like the classification of the genus Camponotus itself.
According to Emery (1925) Karavaievia is closely related to the subgenera Myrmamblys, Myrmoteras, and Myrmoplatys.The most important difference between these subgenera and Karavaievia is the nearly complete absence of any dimorphism in the worker caste of the Karavaievia species.Specific for Myrmoplatys is the scapal insertion near the midlength of the frontal carinae, the depression of the anterior part of the head and the relatively short flagellar segments.Myrmotarsus includes massive and large species with depressed tibiae.Workers of Myrmarnblys have heads that are longer than wide with parallel sides.The characteristics of Karavaievia are as follows: 1 Workers Apart from mid& variability, all workers are monornorphic and about 5.5 mm long.Head trapezoidal, with rounded occipital corners.Head sides convex, occipital margin more or less concave, and anterior margin mostly straight.The eyes are situated behind the midlength of the sides of the head.Length of head subequal t o its width (i.e.CI -100).Clypeus narrow, convex, and without median carina.Its anterior margin almost straight, and in the middle third slightly concave.Frontal carinae relatively short and subparallel to moderately divergent.Mandibles short, with lateral borders strongly curved and 5 teeth on each masticatory border.Antenna1 scapes projecting beyond the occipital margin by about one third of their length.Pedicel longer than the following flagellar segments; apical flagellar segments slightly thickened.Alitrunk with a deep impression (metanotum) between promesonotum and propodeum, and two raised stigmata at the deepest point of the impression.Petiolar scale tapers to a transverse ridge.

Females
Total length about 1 1 mm.Head about twice as wide as that of the workers, and with less convex sides.Anterior clypeal margin with a median semicircular excision.Apical flagellar segments not thickened .

Males
Anterior clypeal margin straight.Mandibles with only one strong, apical tooth.Total outstretched length about 6.5 mm.Frontal carinae extend to about midlength of head.Apart from a slight projection behind the scapal insertion, they are straight and slightly divergent (Fig. 1 a).Anterior clypeal margin almost straight, but in the middle third weakly concave, with slightly indented edges.Eyes are situated behind the midlength of the sides of the head; their maximum diameter is 0.31 mm, or about 0.24 HW.

Camponotus texens
Head and alitrunk dark brown; gaster and petiole dirty yellow.Antennae and legs, including tibiae, dark brown, while apical flagellar segments, tarsi and front of head are dirty yellow like the gaster.Surface of head, alitrunk and gaster weakly shining.Accordingly, cuticular punctures and reticulated sculpture (SEM) are weak (Fig. la, c).Gaster with an imbricate sculpture (Fig. 3b), which is much more pronounced in gaster of males (Fig. 3c).Yellowish white, decumbent pubescence on the whole body, including scapes and legs.Longer erect, yellowish white hair especially on clypeus, but also on rest of head, alitrunk and gaster.Propodeum, seen in profile, broadly rounded and slightly higher than promesonotum.Dorsal part of the propodeum convex, descending part straight.In the lower fifth, the declivity is slightly concave.
Paratype $$ : TL 5. Mandibles strong, distinctly rounded on outside and with 5 subequal teeth on inside.Frontal area not clearly delimited and hardly more shining than surroundings.Head and alitrunk black, tergites  C .Allotype ((5): TL 6.7, HL 1.0, HW 1.02, CI 102, SL 1.00, SI 102, PW 1.32, O D 0.46.The trapezoidal head nearly as wide as long (CI 102), with prominent convex eyes, extending to the upper end of the head sides.Occipital margin strongly convex with protruding ocelli (Fig. 2a); clypeus narrow (width about 0.17 mm) with straight anterior margin.Short frontal carinae sinuate, reaching back to midlength of head.Eyes very large; maximum diameter 0.46 mm, or about 0.45 HW.Scapes long, projecting beyond occipital margin of the head by more than half their length.Pedicel expanded at its distal end and thicker than following flagellar segments.

Camponotus gombaki sp. n.
Derivatio nominis: The name is derived from the Gombak Valley, in which the first and only colony of this species was found, and in honor of the 'Gombak Field Station of the University of Malaya,' where we worked during our research stay.
A. Holotype 9 : T L 6.1, HL 1.46, HW 1.49, CI 102, SL 1 S 6 , SI 96, P W 0.93, O D 0.34.Frontal carinae slightly sinuate, reaching back to midlength of the head (Fig. 4a).Anterior clypeal margin almost straight, but in the middle third weakly concave.Eyes situated behind the midlength of the sides of the head, with maximum diameter of 0.34 mm or about 0.23 HW.
Head and alitrunk reddish brown, gaster dark brown, almost black.Petiole reddish brown at base, but dark brown in upper half.Legs and antennae, like head and alitrunk, reddish brown to top.Surface of head, alitrunk and gaster opaque, with very dense punctures, which appear elongated on the gaster.Cuticular structure under SEM regular reticulated on head and irregular reticulated on alitrunk; cuticular sculpture of gaster is shown on Fig. 3a.Yellowish white, decumbent pubescence less dense than in C. texens workers; yellowish white, erect, longer hairs occur mainly on forehead and vertex, less dense on alitrunk and gaster.Propodeum in profile broadly rounded (Fig. 4c, d) and lower than promesonotal dorsum.Dorsal part of propodeum convex, descending part slightly flatter.In the lower sixth, the declivity is slightly concave.Head, alitrunk, petiole and legs reddish brown; gaster, antennae and mandibles dark brown.Wings yellowish, veins yellow brown.Body covered with short, yellowish white, decumbent pubescence; longer, erect, yellowish white hair is particularly dense on clypeus, but also on rest of body, including scapes and legs.Longer hair on alitrunk is less dense than in C. texens female.Eyes are situated behind the midlength of the sides of the head and markedly larger than those of workers, but smaller than those of C. texens females; maximum diameter 0.54 mm, which is about 0.24 HW.Petiolar profile with broad base, which tapers to a transverse ridge and into a point, as seen from above.
Paratype @: T L 11. Frontal carinae extend to about midlength of the sides of the head; as in C. texens, they are slightly divergent and-apart from a lateral projection behind the scapal insertion-straight.Anterior clypeal margin almost straight, but slightly concave in the middle third.Eyes are situated behind the midlength of the sides of the head; maximum diameter 0.39, which is about 0.39 HW.
Head and alitrunk reddish brown, gaster blackish brown with lighter anterior segment boundaries.Petiole, legs, tarsi, and apical antenna1 flagellum yellow.Head, alitrunk and gaster shining, less punctured than in C. texens and in particular in C. gombaki.Whole body covered with fine, yellowish white, decumbent pubescence; longer erect denser than in C. texens and in particular in C. gombaki.Propodeum in profile broadly rounded and slightly higher than promesonotal dorsum.Dorsal part of propodum weakly convex, descending part slightly flatter.In the lower fourth, the declivity is slightly concave.
On the whole, the differences between C. gombaki and C. texens are not exceeding those between C. overbecki and C. dolichoderoides.As C. texens and C. gombaki certainly belong to different species because of the differences in their behavior (Maschwitz et Psyche [vo~. 92 al., 1985), there is no sufficient reason to continue designating C. overbecki as a variety of C. dolichoderoides.It is therefore made a species on its own.The female of C. overbecki is described by Viehmeyer (1915) from an isolated specimen as follows: head narrower and more elongated than that of worker; eyes larger and more convex than those of workers and situated in front of the midlength of the sides of the head.Clypeus slightly emarginate anteriad.Dispersed, decumbent pubescence on the whole body.Female dealate and 6.5 mm long.
Body length of 6.5 mm is far smaller than that of any other known Karavaievia females.Head deviates markedly in shape and size, and eyes are situated in front of the midlength of the sides of the head and more convex than those of workers.This was not found in any other Karavaievia female.In contrast to all other Karavaievia females, clypeus slightly carinated and emarginated.These basic differences from all known Karavaievia females suggest that the female described by Viehmeyer is not a female of C. overbecki.
Males of C. overbecki as described by Viehmeyer (1915): Head with strongly convex eyes slightly broader than long, occipital margin strongly convex, anterior clypeal margin straight, mandibles with a large apical tooth.Propodeal profile with weakly convex dorsal and concave descending face; dorsal face with shallow, median, longitudinal furrow.Petiolar scale lower and slightly thicker than that of worker, tapering to a transverse ridge, which is slightly excised in the middle.Densely reticulated, front part of the body more opaque than gaster.Dirty yellow brown, gaster with indistinct narrow, dark bands in front of the posterior segment borders, femora and tibiae slightly darkened; wings yellowish with yellow brown veins.6 mm in length.

Camponotus dolichoderoides Fore1
Camponotus dolichoderoides Forel, 19 1 1 : 5 1. (Types not found, presumed lost.)Description is translation of Fore1 (191 1): workers 6 mm in length; strong, curved, shining mandibles, with 5 teeth and widely separated punctures.Clypeus without carina, anterior margin straight, and not or only weakly protruding.Frontal carinae little sinuate and hardly divergent.Scapal insertion close to the posterior clypeal margin.Head trapezoidal, with strongly convex sides, and nearly as broad as long with maximum diameter in the posterior third.Occipital margin moderately concave; eyes situated close beyond t h e midlength of the sides of the head.Scapes project behind the occipital margin by about one third of their length.Apical antennal flagellum slightly thickened.Promesonotal dorsum broadly rounded with deep promesonotal suture.Deep impression between promesonoturn and propodeum, with two raised stigmata on the ground.Dorsal propodeum in profile slightly convex, forming almost a right angle with declivity which is almost straight.Petiolar scale in profile cone shaped.Gaster oval, tibiae cylindrical, not thickened a n d without spines.Cuticular surface weakly reticulated and slightly opaque, covered with punctures which are particularly dense and elongated on gaster.Decumbent pubescence very fine, yellowish, distributed over the whole body, including tibiae and scapes, especially dense on gaster.Uniformly dirty yellow brown; tarsi, apical antennal flagellum and front head reddish to yellow red.Hayvep, Borneo.Original description (Emery, 190 1): workers dirty yellow, shining, front head and gaster lighter, segment borders brownish, decumbent pubescence denser on head and alitrunk than on gaster.Body, including scapes and legs, covered with longer, whitish, erect hairs.Weak cuticular punctures on the whole body, those of the gaster elongated.Head rounded and convex.Clypeus weakly convex and not carinated; anterior clypeal margin with wide excision in the middle third, and indented edges.Mandibles strongly curved o n outside and 5 teeth on inside.Frontal carinae almost straight, linea frontalis weak, but clearly visible.Scapes project beyond occipital margin by about one third of their length.Viewed in profile, proand mesonotum form a curved line which is connected to the propodeal outline by an obtuse angle.Propodeal profile broadly rounded.Scale biconvex, tapering into a sharp transverse ridge.Length: 4-314 to 5-1 / 2 mm.

Carnponotus exsectus Emery
According to my own examination, workers are more shining than those of C. texens, but not as much as those of C. gombaki.

Comparison of Karavaievia Species
The subgenus is characterized by morphological traits a n d possibly by behavioral characters, too.The common morphological traits include the subuniform size of workers, females and males, the shape of the head, the position of the eyes, the characteristic shape of frontal carinae, clypeus, mandibles, antennae and alitrunk.All known Karavaievia species originate from the Indo-Malayan area, in particular from Malaysia and Singapore.A possibly common behavior of all Karavaievia species is the weaving of silk nests on the undersides of leaves which, however, has only been investigated for C. texens and C. gombaki (Maschwitz et al., 1985).F o r C. overbecki, there is only the statement of Viehmeyer (1915) that Overbeck found workers and males in 'carton nests' on the underside of leaves.Nothing has become known so far, however, on the nest-building of C. dolichoderoides and C. exsectus.
My examination of two workers and a male of C. texens and of two workers of C. gombaki showed no openings of metapleural glands.This is in accordance with the observations in a l l weaver ants studied by Holldobler and Engel-Siege1 (1984).
The two species described by Fore1 (191 1) as C. horrens and C. moeschi, found on the Philippines, were assigned by Fore1 (19 1 1) to the same group as C. dolichoderoides, and also Chapman a n d Capco (1951) classified C. horrens in the subgenus Karavaievia.Emery (1925), on the other hand, classified C. moeschi in the s u b g enus Myrmamblys and C. horrens in the subgenus Colobopsis; in the latter case, however, Emery was not quite sure, because n e i t h e r soldiers nor females of this species had been found.C. horrens a n d C. moeschi definitely do not belong to the subgenus Karavaievia.This is supported in the case of C. horrens by the carinated a n d twice-excised anterior clypeal margin of the workers, the strongly divergent frontal carinae and the position of the eyes in the posterior fourth of the head.Features against C. moeschi as a member of the subgenus Karavaievia are the notched clypeus, lobed in the a n t e r i o r part; the elongated head, convex in the occipital part; position of the eyes at the posterior third of the head, and the weakly impressed metanotal groove.
The differences between workers of the Karavaievia species are in coloration, sculpture and pubescence, slight differences in the s h a p e of the frontal carinae, differences in size of head and eyes, and in shape and size of propodeum.A broader comparison of the Karavaievia sexuals, however, is not yet possible, because females o f o n l y 3 species and males of 2 species are known.Karavaievia workers are dirty yellow and brown, from reddish brown to blackish b r o w n ; in most cases, the front of the head, the apical flagellar segments a n d the tarsi are of a uniform color, which differs from the color of the rest of the body.

Fig. 1 .
Fig. 1.Scanning micrograph of Camponofus [exens: a, head of worker; b, head of female; c, alitrunk of worker in profile. of gaster dark brown; sternites lighter brown; front of head, distal antenna1 flagellum and legs yellow brown.Wings yellowish, veins yellow brown.Head, alitrunk and gaster covered with fine, light yellow, decumbent pubescence.Longer erect hairs distributed over the whole body.Eyes distinctly larger than those of workers and situated behind the midlength of the sides of the head.OD 0.69 mm, o r about 0.30 HW.Petiole with a broad base, tapering toward the apex into a narrow ridge, seen from the side.

Fig. 4 .
Fig. 4. Scanning electron micrograph of Camponotus gombuki; a, head of worker; b, head of female; c, alitrunk of worker in profile; d, petiole of worker, with parts of alitrunk and gastcr in profile.

[Vol. 92 Erect
hairs more numerous than in C. texens.Propodeal dorsum clearly higher than dorsum of promesonotum, and in profile more inclined than in C. texens, C. gombaki, and C. overbecki.Dorsal part of propodeal profile convex, descending part nearly straight.Frontal area clearly delimited.Original description of female (Emery, 1901): d a r k e r than workers; sides, scutellum, propodeal dorsum, legs, and m a j o r part of gaster brown.Head and mesonotum opaque; pubescence very dense, in particular on gaster.Head trapezoidal, mandibles similar to those of workers; clypeus narrow with deep semicircular excision in the middle of the anterior margin, limited by protruding acute angles.Antennae strong, petiole similar to that of workers.Punctures on gaster weak and not elongated.Length 11 mm.Mentawei, Sipora.According to my own examination, C. exsectus females a r e larger than females of C. gombaki and C. texens.HW 2.5, HL 2.5, PW 2.3.Frontal carinae less divergent than those of C. texens a n d C. gombaki females.Frontal area indistinctly delimited; mandibles reddish brown with black teeth; gaster shining.