A new inquiline ant (Hymenoptera: Formicidae) in Cataglyphis and its phylogenetic relationship
Author
Agosti, D.
text
Journal of Natural History
1994
1993-10-20
28
913
919
journal article
10.5281/zenodo.2949937
54b2150d-e662-450d-b3c2-73b51ac32041
2949937
Cataglyphis
hannae
n. sp.
Material examined
Holotype: <?, HL 1-40, HW 1-20, EL 0-50, SL 218, AL 2-63, CI 86, SI 181, El 41-7, FI 35-4, LI 100-8, TAI 114-3.
Diagnosis of male
Ant of the
Cataglyphis bicolor
species group (
Agosti, 1990
), with the following diagnostic features:
(1) Black head and alitrunk.
(2) Alitrunk length 2-63 mm.
(3) Subgenital plate distally trilobed with the median process triangular and not digitiform.
(4) In ventral view, median process with hair-carrying pits to the tip.
(5) In lateral view, apicolateral appendix of sagitta not overreaching outline of apical, serrated plate.
(6) Apicolateral appendix of sagitta short and terminally rounded; in ventral view only slightly raised above the plane of the apical, serrated plate.
(7) Long hind tibiae (TAI 114-3).
Paratype
: ♂ ♂ HL 1-30-1-43, HW 1-05-1-19, EL 0-44-0-50, SL 1-98-2-23, AL 2-48-2-73, CI 80-8-86-6, SI 175-5-195-6, El 41-1-43-0, FI 91-4-103-2, LI 101-7-105-5, TAI 108-3-116-0 (
n
= 8).
There is a slight variation in size, but the extremes of the range of absolute measurements are always far below those of the other males of the
bicolor
species group. Compared with all the other males of the
bicolor
group,
hannae
has the longest hind tibiae (TAI> 108). Head and alitrunk always black in colour.
Diagnosis offemale
Ant of the
Cataglyphis bicolor
species group with the following diagnostic features (
Fig. 1B
):
(1) Small size, alitrunk <3-2 mm.
(2) Scape much longer than head length (SI> 120).
Fig. 1. Lateral view of the females of
C
.
bicolor
(A) and its inquiline
C. hannae
n.sp.
(B). Hairs are only drawn on the occiput.
(3) Long hind tibiae (TAI> 90).
(4) Head and alitrunk bright red.
(5) First funicular segment of intermediate length (28 <FI <35).
(6) Low rounded petiole in lateral view.
Paratypes: ♀ ♀ HL 1-75-1-88, HW 1-65-1 -73, EL 0-48-0-50, SL 2-00-2-18, AL 2.95-3.13, CI 90-4—94-3, SI 121-2-129-9, FI 29-0-31-1, El 28-4-29-0, LI 101-8-107-1, TAI 93-5-100-8 (
n
= 5).
Deposition of type material
Holotype
:
♂
,
Tunisia
,
El Guettar
,
34.33°N
,
8.92°E
,
300 m
; in
Oasis, at the edge of irrigated fields under
Eucalyptus
trees
,
D. Agosti
,
0 8.06.1992
, sample
F92039
,
in nest with
Cataglyphis bicolor
(
MHNG
).
Paratypes
:
5 ♀
♀
, (alates) and
14 ♂
♂
, same as holotype.
7 males
,
Tunisia
,
El Guettar
,
34.33°N
,
8.92°E
,
300 m
; in
Oasis, at the edge of an irrigated lucerne field
,
D. Agosti
,
0 8.06.1992
, sample
F92309
, in
nest with
Cataglyphis bicolor
(
BMNH
,
CDA
,
CRW
,
MCZ
,
MHNG
).
C. hannae
can be separated from all the other known species in the
bicolor
group by the above mentioned diagnostic characters, especially by the body size, the long antennal scape and hind tibiae, the low rounded petiole, and the male genitalia.
C. abyssiniens
,
the only species with small females, has a much shorter scape (SI <113), and shorter hind tibiae (TAI <85); no males of this species are known. The long black hairs on the occiput of the head as seen in
bicolor
are not present in
hannae
,
and thus exclude the possibility of
hannae
being a microgyne of
bicolor
.
Although
>
1500
different samples of species of the
bicolor
complex are in our collections, and most of them from Tunisia, no further
hannae
specimens have been collected before. The host of
hannae
is distributed along the southern foothills of the Atlas mountains in the transitional zone from the Mediterranean to the Desert region, not reaching the Atlantic in the West and not extending into Libya (Agosti
et al.,
in preparation). Thus,
hannae
might be more common, certainly if one considers that the southern extension of the Mediterranean vegetation during the Pleistocene reached as far south as the Saharan mountains Tassili and Hoggar (
Quezel, 1965
). But social parasitic ants tend to have a clumped distribution (
Buschinger, 1985
) and the restricted collecting area might truly reflect its distribution.
Finally, these males and females were collected as alates, during a survey where
>
200
nests were at least partially dug up.
The habitat was at the edge of an irrigated
Medicago sativa
field and on a sandy place in the shade of some tall
Eucalyptus
trees on the side of a track within the oasis. In this desert region, the occurrence of species of the
bicolor
group is restricted to oases.
The position of
hannae
within the
bicolor
species group is established by the male genitalia and the funicular index of the female. More problematic, and challenging, is the sister group relationship within the
bicolor
group. A phylogenetic analysis using morphological characters of
nodus
(outgroup),
abyssinicus, bicolor, savignyi, viaticus
(
Table
1
) and the explicit enumeration procedure from the computer program Hennig86 (
Farris, 1988
), resulted in 3 most parsimonious trees. Subsequent successive weighting established 2 most parsimonious trees (
Fig. 2
). Both these trees share the sister group
hannae + abyssinicus,
and support a sister group
viaticus + (hannae + abyssinicus).
The sister group relationship of
hannae + abyssinicus
is so far only supported by female characters, as the males of
abyssinicus
are unknown. However, the long antennal scape and the small size of the females of
abyssinicus
,
which is the same as in
hannae
and unique in species of the
bicolor
species group, indicate an inquiline life style for this species too. A more detailed discussion will be provided by Agosti (in preparation).
Table 1. Data matrix. One ri: SI> 170 (character state 0), SI <170 (1); 2 Queen: CI> 95 (0), C K 9 5 (1); 3 Q: S I<105 (0); SI>105 (1); 4 Q, TL<3-5mm (0), TL<3-5mm (1); 5 Q, TAI <90 (0), TAI> 90 (1); 6, Q, white hairs on occiput of head (0), black hairs (1); 7, Q, head and alitrunk bright red (0), dark red to black (1); 8 M, lateral apical appendage of subgenital plate digitiforme, parallel sided (0), triangular (1); 9 M, median apical appendage of subgenital plate in crossection (at midlength) rounded (0), angular (1); 10 M, Sagitta with antero-lateral appendage convergent at base (0), parallel sided at base (1); 11 M, in lateral view, antero-lateral appendage of sagitta crossing outline of apical blade (0), not extended beyond (1); 12 M, median appendage of subgenital plate shorter as lateral appendages (0), of same length (1); 13 M, antero-lateral appendage of sagitta apically pointed (0), rounded (1). (A full discussion of the characters, and coding, based on> 1000 specimens, will be provided elsewhere (Agosti, in preparation).
| Species |
Characters |
| 1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
|
Nodus
|
1 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
1 |
|
Hannae
|
0 |
1 |
1 |
1 |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
|
Abyssinicus
|
- |
1 |
1 |
1 |
0 |
0 |
1 |
- |
- |
- |
- |
- |
- |
|
Bicolor
|
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
|
Savignyi
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
|
Viaticus
|
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
Fig. 2. Phylogenetic relationships of
Cataglyphis hannae
n. sp.
Two most parsimonious trees shown with a consistency index
(ci)
of 98 and a retention index
(ri)
of 96. The synapomorphies for the sistergroup
hannae
+
viaticus
are small body size (characters 3 (1) in Table 1), and long antennal scape (4 (1)); for the sistergroup
viaticus
+ (
hannae
+
abyssinicus
)
the synapomorphies are bright red colour of head and alitrunk (7 (1)) and shape of median appendage of the male subgenital plate (9 (0)).
As all the results are based on morphological characters, it would be interesting to test them using other characters such as DNA sequences, electrophoretic data or the chemical composition of glandular compounds, all of which have already showed their specificity at the species level (
Keegans
et
al., 1992
; Agosti
et al.,
in preparation).