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Описание нового для науки вида муравьёв Anochetus bytinskii, обнаруженного в Израиле.
РЕФЕРАТ.
Новый вид Anochetus bytinskii описан из Израиля по рабочим, самцам и самке. Вид A. bytinskii близко родственен и сравнивается с видами A. ghilianii (Spinola)
и A. traegaordhi Mayr. Обсуждается распространение вида A. bytinskii в Средиземноморье и его тип гнездования. Предложен определитель муравьёв рода Anochetus по рабочим особям, распространённых в Средиземноморском регионе и на Ближнам Востоке.
KEY WORDS: Anochetus bytinskii n. sp., Israel, key
Фауна муравьёв Израиля
ВВЕДЕНИЕ.
The genus Anochetus Mayr includes 96 species (Bolton, 1995; http://antbase.org/) and
has a mostly tropical and sub-tropical distribution. Only few species have been recorded
from Mediterranean and Middle East localities to date: A. evansi Crawley, endemic
to Iranian Kurdistan (Brown, 1978); A. ghilianii (Spinola), restricted to Morocco and
southern Spain (Emery, 1909; Brown, 1964; Tinaut, 1989); A. sedilloti Emery, a species
with a wide range of distribution from Tunisia and sub-Saharan Africa through Saudi
Arabia to western India (Forel, 1900; Brown, 1978; Collingwood and Agosti, 1996);
and A. traegaordhi Mayr, described by Mayr (1904) from Sudan and recorded from
many places throughout Africa (Santschi, 1910; Weber, 1942; Arnold, 1946; Bernard,
1953; Brown, 1978), and also from Saudi Arabia (Collingwood and Agosti, 1996).
Little is known about the biology of Anochetus, probably due to widespread
cryptobiosis in this genus (Brown, 1978). In the ghilianii group, A. ghilianii has well documented subterranean habbits and, as argued by Tinaut (1989), this species may
have survived the glacial period due to cryptobiosis. The habits of A. traegaordhi are
less known and mostly comprise anecdotic data: a nest was discovered in Zimbabwe
in sand soil (Arnold, 1946); another nest was discovered in Sudan under a tree trunk
(Viehmeyer, 1923); and Collingwood (1985) noted that 2 Saudi specimens were collected
on the surface foraging under bushy scrub. More information exists on populations of A.
traegaordhi from Cameroon and Congo that specialize in feeding upon termites of the
genus Nasutitermes and nest in logs occupied by their prey (Schatz et al., 1999).
A species of Anochetus from Israel was first mentioned in 1975, as Anochetus israelis
n. sp., by the late Prof. Bytinski-Salz in an unpublished “List of Formicidae of Eretz Israel
from Mount Hermon to Sinai”. However, because the list was never published and the
ant was not described, this name remained invalid. Subsequently, Kugler (1988) listed
Anochetus n. sp. as supposedly an endemic ant for Israel, “close to” the Afrotropical
species, A. traegaordhi, and the west-Mediterranean species, A. ghilianii. In this paper
we describe this new species as A. bytinskii and compare it to several related species.
Measurements and indices
Measurements (in millimeters) were made with a stereoscopic microscope (LEICA
MZ 8), fitted with an ocular micrometer, at 50x magnification; and indices are reported
as percentages. We essentially follow the abbreviations of Brown (1978) and the
measurements and ratios used by Arnold (1946), Brown (1976, 1978), Forel (1915) and
Viehmeyer (1923).
TL – Total Length, including mandibles
HL – Head Length, including occipital lobes
HW – Head Width
CI – Cephalic Index (= 100xHW/HL)
ML – Mandible Length
MW – Mandible Width, measured as maximum width when head in full-face view,
dentition excluded
MI – Mandibles Index (= 100xML/HL)
EL – Eye Length
EI – Eye Index (= 100xEL/HL)
SL – Scape Length
SI – Scape Index (= 100xSL/HW)
AL – Mesosoma Length
pNW – Pronotum Width
mNL – Mesonotum Length
mNW – Mesonotum Width, measured by excluding the striae or costae of the bordering
sutures
PL – Petiole Length
PW – Petiole Width, measured in dorsal view and excluding anterior and posterior
peduncles
PI – Petiole Index (= 100xPW/PL)
PNL – Petiolar Node Length, measured as maximum thickness in lateral view
PNH – Petiolar Node Height
PNI – Petiolar Node Index (= 100xPNH/PNL)
GL – Gaster Length
G1W and G2W – First Two Gastric Segments Width, measured in dorsal view
GI – First Two Gastric Segments Index (= 100xG1W/G2W)
pTbL – Pro-Tibia Length
Anochetus bytinskii Kugler and Ionescu, n. sp.
Description
Worker. Measurements. TL 5.83–6.98, HL 1.42–1.61, HW 1.21–1.38, SL 1.22–1.41,
EL 0.18–0.22, ML 0.75–0.87, AL 2.00–2.23, pNW 0.65–0.74, mNW 0.36–0.47, PL
0.34–0.42, PNH 0.26–0.36, GL 1.41–2.00, G2W 0.76–0.92, pTbL 0.96–1.13, CI 84.2–
87.7, SI 97.5–105.7, EI 11.8–14.8, MI 50.3–56.8, PI 72.0–84.7, PNI 84.4–106.3, GI
93.9–100.0 (N = 46).
Head (Fig. 1). Vertex deeply concave; shallow depression in front of rounded nuchal
carina; median furrow absent, except smooth and shiny strip that enlarges in shallow
depression at level of posterior margin of orbital fossa. Eye with 8–11 ommatidia across
greatest diameter; ocelli absent. Scape slightly curved, barely reaching or slightly
surpassing occipital lobe; funiculus 11-jointed, second segment L/W (length-width
ratio) 1.9–2.3, about equal to third and fourth segments. Mandible slender, W/L 0.23–
0.27, broadened at distal half; medial edge with 2 nearly straight margins extending to
semicircular preapical excision; ventral margin with series of 6–11 distinct, rounded
denticles followed distally by 3–4 denticles fused into crenulated laminar process;
denticles hidden from view by dorsal margin of mandible when head in “full-face” view
and mandibles closed.
Mesosoma (Fig. 2). Slender, pNW/AL 0.31–0.35, with well-marked pro-mesonotal
and meso-metanotal sutures; pronotum sub-pyriform; mesonotal disk convex, wider
than long, W/L 2.00–2.79; propodeal dorsum straight to slightly depressed transversely
behind metanotal spiracle, narrow, smoothly rounded into declivity; no traces of
propodeal angles or teeth; declivity slightly convex in transversal plane.
Petiole: distinctly longer than wide. Petiolar node triangular in lateral view (Fig. 2),
about as high as long, with rounded apex. In dorsal view, contour of base anteriorly
ogival, posteriorly straight, with median concavity (posterior face flat, with feeble
vertical sulcus); dorsal margin more or less compressed transversely – apex with
distinctly transverse summit only in four of the largest specimens. In anterior view
laterally arcuate with bluntly rounded apex (Fig. 3).
Gaster. Sub-cylindrical, weakly constricted between first 2 segments; first gastric
segment narrower than second in 39 out of 41 examined specimens, and about as broad
as long.
Sculpture. Head punctulate, smooth and shiny except frontal striation; striae fine but
distinct, medially 0.20–0.28 mm long; striae fan out posterolaterally, extending just
posterior to frontal carina, and to level of posterior margin of compound eye, laterally
entering antennal hollow but not exceeding posterior and lateral margins. Pronotum
mostly smooth and shiny; cervix distinctly transversely striate with curved ruga, and
posterior to ruga few fine, superficial striae arched parallel to margin; laterally smooth
and shiny, finely punctuate; disc with scattered and coarse punctuation in 34 of 46
specimens, superficially and patchily rugo-striate toward margins in concentric pattern
in other 12 specimens. Mesonotal disc crossed by up to 13 fine striae, although in 27
specimens anterior half more or less shagreened or striolate and strongly shiny. Dorsum
of propodeum patchily rugo-striate and/or vermiculate on anterior third, posteriorly
superficially cross-striate (11–16 striae per 0.2 mm); 2–11 striae present toward base of
declivity; striae usually visible only in certain illumination, but in six specimens striation
distinctly visible on propodeal dorsum and declivity, whereas in eight specimens striae
too superficial to be counted; propodeum laterally with oblique striae. Mesopleuron
and metapleuron smooth and shiny; ventral extremity of metapleuron with few oblique,
strong rugae. Gaster and coxae smooth and shiny, sparsely punctulate. Antenna and
mandible fine and densely punctulate.
Pilosity. Fine. Longest hairs (L 0.1 – 0.2 mm) abundant and decumbent on gaster, sparse
and erect to suberect in bucal region and on coxae, absent on mesosoma, except one
suberect hair on pronotal disk. Shorter hairs (L 0.04 – 0.10 mm) fairly abundant on head
and thorax, sparse on propodeum and first gastric segment, obsolescent caudad; these
hairs appressed to subappressed on most of head, pronotum and propodeum, erect on
frontal carina, decumbent to erect on mesonotum, decumbent on gaster. Appendages
covered by even shorter, appressed to decumbent pubescence. Propodeum nearly
glabrous in few specimens.
Color. Living individuals yellow with orange tint. Dry specimens brownish yellow,
lighter on mesosoma and coxae; gaster with brownish shading; epistoma, tip of mandible
and leg brown.
Gyne. Measurements. TL 6.63, HL 1.37, HW 1.27, SL 1.22, EL 0.23, ML 0.71, AL
2.13, pNW 0.69, mNW 0.49, PL 0.41, PNH 0.35, GL 2.27, G2W 1.28, pTbL 0.97, CI
93.1, SI 96.1, EI 16.6, MI 52.2, PI 96.5, PNI 109.1, GI 96.9 (N = 1).
Dealate specimen, size (TL) of average workers, although with protibia length similar
to that of smallest workers.
Head (Fig. 4). Slightly shorter and markedly broader than in worker with similar tibia
length. Eye with 13 ommatidia across greatest diameter; ocelli absent. Mandible as in
worker, W/L 0.25.
Mesosoma (Fig. 5). More robust than in worker, but with similar proportions; scutum
W/L 1.32; scutellum hexagonal, with rounded edges, convex, L 0.19, W 0.27 mm;
dorsellum elliptical, L 0.08, W 0.20 mm. Remnants of wings visible as dark brown
stumps.
Petiole. Oval, broad, W 0.37 mm, only slightly longer than wide, node scale-like, more
compressed fronto-caudally and higher relative to length than in workers (Fig. 6).
Petiole. Oval, broad, W 0.37 mm, only slightly longer than wide, node scale-like, more
compressed fronto-caudally and higher relative to length than in workers (Fig. 6).
Gaster. Longer and wider than in largest worker, sub-cylindrical, weakly constricted
between first two segments, first tergite distinctly broader than long.
Sculpture. Head as in worker; pronotal and mesonotal disc and scutellum smooth and
shiny. Propodeum laterally with oblique striae and coarse punctuation, declivity with 15
fine, transverse striae. Mesopleuron and metapleuron smooth and shiny. Gaster, coxae
and head laterally shiny and sparsely punctulate.
Pilosity. More abundant on mesosoma, as compared to workers, most hairs decumbent
to suberect; on gaster predominantly suberect pilosity in contrast to mainly decumbent
pilosity of workers.
Color. Similar to workers.
Male. Measurements. TL 4.17–5.02, HL 0.85–0.87, HW 0.98–1.00, ML 0.12, AL 2.05–
2.09, EL 0.50–0.53, PNL 0.340.39, GL 1.97–2.35, fore wing L 4.11–4.19 (N=10).
Head. With large compound eyes; three ocelli, raised (Fig. 7), shortest distance to
compound eyes equal to four ocelli diameters, shortest distance to antennal sockets
equal to three ocelli diameters; mandibles reduced, cuneiform. Scape about twice as
long as wide, first funicular segment as long as wide.
Mesosoma. Robust, with convex dorsum and nearly straight pleura; propodeum convex,
dorsum rounded into declivity (Fig. 8).
Petiole. Node low, height about 0.5 of length, triangular in lateral view, apex bluntly
rounded (Fig. 8); dorsal margin shallowly concave in anterior view; anterior face flat;
lateral margins almost straight and slightly convergent (Fig. 9).
Gaster. Cylindrical, slightly constricted posterior to first segment. Terminalia partly
retracted (Fig. 8); pygidium broadly rounded; subgenital plate narrowed caudally into
median digitiform process (Fig. 10); cerci present; paramere broad, developed ventrally
and apically into linguiform expansion (Fig. 11).
Sculpture. Large, coarse punctures on head, mesosoma and gaster. Frons and mesosoma
dorsum rugged, propodeum transversely rugulo-striate.
Pilosity. Body covered by dense, short, decumbent, golden pubescence, somewhat
longer on gaster; antennae and legs with shorter, more abundant apressed to decumbent
hairs.
Color. Body predominantly black, antenna and coxae dark brown, terminalia, tibiae and
tarsi lighter brown to yellowish brown. Wings transparent with brownish tint, venation
and stigma light brown.
Material examined
Holotype worker, ISRAEL: Migdal Afeq, 20.iv.1985, J. Kugler and D. Simon, No. 6484.
Paratypes: same collection data as holotype (17 рабочих, 10 самцов, emerged from cocoons in the laboratory, 4.31.v.1985); [Qiryat] Tiv'on, 11.vii.1989, J. Cnaani (2 рабочих); Elyaqim, Karmel, 23.iii.1989, J. Kugler (11 рабочих, 1 самка); Karmi'el, 18.ii.2005, Th. Assmann (5 рабочих); Oranim [near Qiryat Tiv'on], xi.1959, M. Costa (3 рабочих); Oranim, 19.iv.1972, J. Ofer (1 рабочих); Hirbet Usha, 2.vii.1985, D. Simon (11 рабочих). The holotype and paratypes are deposited in the entomological collection of Tel-Aviv University, Israel (TAUI).
Etymology
The new species is named after the late Prof. Hanan Bytinski-Salz, whose work on the
ants of Israel inspired us. Prof. Bytinski-Saltz was the first to note the presence of this
species among the Israeli fauna.
Biology and ecology
The nests of A. bytinskii are subterranean. Brood-containing cocoons (N=20) were found
inside a chamber of such a nest together with workers, but without eggs and larvae. They
were kept in the laboratory till the emergence of the last adults, all males, over a period
of 27 days.
The distribution of A. bytinskii is limited to the northern half of Israel, from the
Karmel Ridge and the Lower Galilee to the Foothills of Judea. This species is apparently
cryptobiotic as alluded by the subterranean nature of the nests that, together with their
openings, were often found under large stones.
Affinities
We compared workers, a gyne and males of A. bytinskii n. sp. with the same casts of
A. ghilianii, A. sedilloti and A. traegaordhi, whenever available (see Appendix 1 for
collection data) and with A. evansi (based on the literature only: Crawley (1922) and
Brown (1978)). The main differences among workers of these species are also presented
in the following key. However, as A. traegaordhi is apparently a complex of several
Afrotropical species (Bolton, personal communication), we based the key on the East-
African material only, including the holotype, and did not include the studied specimens
from Congo, the latter not keying well to any of the species.
Workers: A. bytinskii is most similar to the East African A. traegaordhi, and the
two species share similar head, antenna and mandible shape, and pattern of pilosity
distribution. A. bytinskii has a distinctly weaker sculpture especially on the head and
propodeum, much shorter frontal striation (L < 0.19 as compared to L > 0.35 of HL),
and noticeably smaller eyes (L < 0.23 mm as compared to L > 0.24 mm).
Gyne: A. bytinskii differs from A. ghilianii and A. traegaordhi by the rounded,
slightly convex declivity of propodeum as compared to a transversely concave declivity;
weak and short frontal striation, as compared to a strong striation, extending to the
posterior ocellus (Fig. 12); and the rounded petiolar node summit, as compared to an
indented petiolar node summit in the other two species (Figs. 13, 14). A. bytinskii differs
from A. sedilloti (based on the descriptions by Forel (1900) and Finzi (1939)) by the
mostly smooth and shiny pronotum, mesopleuron and metapleuron as compared to a
longitudinally striate pronotum and coarsely striated mesopleuron and metapleuron.
Male: A. bytinskii differs from A. ghilianii by the smaller ocelli, less bulky propodeum,
cylindrical gaster (slightly conical in A. ghilianii), and distinctly fewer erect antennal
hairs. The petiolar node is dorsally shallowly concave with rounded summit in lateral
view in A. bytinskii, whereas bidentate with deeply incised dorsal margin, and with
sharply pointed summit in lateral view in A. ghilianii (Figs. 15 and 16). The subgenital
plate of A. bytinskii is posteriorly strongly narrowed, whereas that of A. ghilianii has
elongated triangular shape without becoming caudally digitiform (Fig. 17). In dorsal
view the concavity of the paramere is markedly narrower in A. bytinskii and in lateral
view the caudally constricted part of the paramere is about twice as narrow as that of A.
ghilianii (Fig. 18). A. bytinskii differs from A. sedilloti (Forel, 1907; Santschi, 1907) in
the dorsal margin of the petiolar node concave as compared to convexly rounded; and
subgenital plate apically digitiform as compared to rectangular, linguiform.
ОПРЕДЕЛИТЕЛЬ ПО РАБОЧИМ МУРАВЬЯМ
Key to workers of Anochetus species of the Mediterranean region
and the Middle East
1. Eye length < 0.13 mm; inner margins of mandible edentate (Iran) .................................evansi
-. Eye length > 0.15 mm; inner margin of mandible denticulate ................................................ 2
2. Scape short, not extending to occipital lobe, SI < 85; length of second and third Funicular
segments subequal; large eye, EI > 20; mesopleuron and metapleuron striate (Tunisia, Eritrea,
Saudi Arabia, western India) ................................ sedilloti
-. Scape longer, extending to or surpassing occipital lobe, SI > 90; length of second and third
funicular segments equal; eye smaller, EI < 20; mesopleuron and metapleuron largely
smooth .....................................................................3
3. Mesonotal disc about twice as wide as long or wider; propodeal declivity smoothly rounded
in vertical and horizontal plane; petiole distinctly longer than wide (PI < 86), node about as high as long (PNI < 106), summit more or less rounded; cross striation on propodeal dorsum finer than on pronotal cervix, or obsolete (Israel) ............................................. bytinskii n. sp.
-. Mesonotal disk W/L < 2; propodeal declivity bordered by elevated ridges (costae) and/or
declivity transversely concave posterior to transition from dorsum; petiole about as broad as
long or broader (PI > 86), node higher than long (PNI > 110), with transverse summit; cross
striation on propodeal dorsum equally strong or stronger than on pronotal cervix ................. 4
4. Eye length 0.16 – 0.22 mm in greatest diameter; mesonotal disk finely rugged, shagreened and
dull; petiolar node scale-like, laterally strongly rounded; first gastric segment narrower than
second or equally wide; antenna, mesosoma dorsum and tarsi with many strong suberect to
erect hairs (Morocco, Southern Spain) ........................................................................ ghilianii
-. Eye length > 0.24 mm in greatest diameter; sculpture of mesonotal disk variable, from striolate and strongly shiny to completely cross-striate; petiole width variable, node with parallel margins; first gastric segment broader than second; pilosity fine, antenna, mesosoma dorsum and tarsi with few suberect to erect hairs (Sudan, Eritrea, Saudi Arabia) ..............traegaordhi
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