Main species pages - Tetramorium simillimum and Tetramorium caldarium

Mostafa Sharaf (email 19.ii.2009) wrote - Please, let me discuss with you in an important point concerning Tetramorium simillimum page in our web site Egypt simillimum I have some specimens kindly sent to me by Barry Bolton of some simillimum from Congo, I have sent him some specimens I identified as T. simillimum but he mentioned they could be caldarium, therefore, I am studying both species for a long time and I can say that our specimens in the mentioned page (collected from Abuzabal, Qaliobia, 13.vi.2003) are not simillimum but caldarium, this point of view was supported by Barry. In this specimens we can find a less developed frontal carinae, less developed antennal scrobes, head in full-face view completely matching the drawing of Bolton (1979). In addition, by comparing simillimum from Congo and caldarium from Egypt I found that the pilosity in the former is much more shorter and less abundant while it is relatively longer and more abundant in caldarium. The general sculpture in our specimen is less developed comparing simillimum. Moreover, the alitrunk dorsum sculpture different from that of simillimum which is faintly longitudinally rugoulose. In brief, I am satisfying that the Egyptian specimens could be of caldarium. Please, let me know your opinion. Sure, your identification of caldarium in Egypt caldarium of Kaseh tourism village in Marsa Matrouh is correct.

Bolton (1980: 303) states firmly that the members of the simillimum-complex and the poweri-complex (including caldarium) can be separated by the latter having frontal carinae that are feeble, variously reduced or absent; additionally they have vestigial or no antennal scrobes. In the case of caldarium this is seems misleading, as the specimens I have or have seen, including Bolton's own 1979 drawing, have distinct, albeit fine, frontal carinae that stretch back to the occiput and there is a distinct shallow antennal scrobe. Extracting from Bolton's key to Afrotropical species (shown below) confirms this regarding the carinae. Couplet 163, however, separating species on the basis of the erect hairs on the dorsal alitrunk and shape of the face, is misleading. All of the six specimens of caldarium of which I have photographs have short, quite fine and distinctly sharp hairs on the alitrunk. The situation with simillimum is very confusing. At least in part, this is due to Bolton's predilection for synonymizing venerable subspecies and varieties. In his three works (1977, 1079 and 1980) he illustrates simillimum with drawings showing very short erect hairs on the alitrunk. In no case does he give any details on the source specimen. The hairs are thick and blunt in the 1977 Asian paper (when he had caldarium as a synonym of simillimum) and the 1979 Malagasy & New World paper. That shown in the Afrotropical paper (1980) appear somewhat thinner. The last is matched in my own drawing (Taylor, 1980: 51). The clypeus in my drawing is smooth other than a median carina, whereas that in Bolton (1979) has a strongly striate clypeus. Mine has only a single pair of erect lateral hairs on the occiput whereas the Bolton specimen has four or five pairs spread out right across the occiput.

All in all, I have serious doubts that lead me to two very different conclusions.

First - there is a single very "plastic" species - the "Myrmica simillimum" of F Smith (1851: 118), the type of which is long lost and came from "Dorset, England" (a strange location but presumably like the type of Tetramorium caldarium found in a hothouse with plants of tropical origin). This includes the various "Tetramorium caldarium" forms, of which Bolton (1980: 310) wrote there might be two species.

Second - there is a set of distinct but basically similar species. These can be traced through Bolton's 1980 key:

Tetramorium simillimum variations

Forms with erect hairs on head and alitrunk short and thick	.
	Bolton (1979) - probably a New World specimen but no collection details given; note he states the cephalic ground sculpture is of "strong reticulate-puncturation", making the head look much rougher than that of caldarium. Yellow to yellow brown, often with the gaster darker. See
	Mauritius - collated from http://www.antweb.org/specimen.do?name=casent0102390 Information: Specimen Code CASENT0102390; Locality; Mauritius: [Round I.]; Collection codes: ANTC4614; Date: 1975; Collected by: D.Bullock.
Sub-Saharan form	Bolton (1980) illustration similar to but at least the head shape different to his 1979 illustration. See . Erect hairs on head and alitrunk described solely as "sparse, short blunt stout hairs".
	Nigeria - Cocoa Research Institute, Taylor, 1980a: 51. WORKER. TL 2.02 mm, HL 0.51, HW 0.48, SL 0.40, PW 0.31 Head, alitrunk and pedicel finely punctate with the puncturations generally arranged longitudinally. Erect hairs stout and moderately abundant. Propodeal spines short, triangular and upturned. Petiole node short, with the anterior and posterior faces near vertical; dorsum flat in profile but sloping downwards to the posterior. Small acute subpetiolar spine. Colour yellow-brown, gaster dark and shiny. Specimen among those listed as examined by Bolton (1980)
	Cameroun 95 - south-western tropical coastal forest area between Edéa and Campo (McKey Wolbachia project) - Cameroon 95 from Kribi (2°56' N 9°55' E, altitude 13 m, coastal), 15 April 2001, in herbaceous vegetation, about 20 cm tall, in garden of Catholic Mission Similar images of workers from Cameroun; Balangue; aphid survey; 31.viii.2008 (fk unmounted 07); collector A Fotso Kuate; from Nko'ondo; aphid survey; 28.vii.2010 (fk unmounted 53); collector A Fotso Kuate; from Mbanga; aphid survey; 1.ix.2008 (fk unmounted 16); collector A Fotso Kuate;; and from Boga; 3°53'60"N 10°46'60"E; lowland area elevation <250m; quadrat in mixed crop field; 28.ix.2007 (fk tetramorium sp 3); collector. A Fotso Kuate.
	Congo - Réserve de Lésio-Louna, S 03°16'21.7" E 015°28'12.5"; n sp 22; pitfall trap 09, t 2.1; 8-9.xi.2007; gallery forest; collector by Eric Zassi
Forms with short stout erect hairs all over; the gaster shiny quite dark brown	.
	Congo - collection t 1.2; 19.viii.2007; pitfall trapped by Yves Braet & Eric Zassi
	Egypt - Qaliobyia; collector Mostafa Sharaf
	Egypt - Kaseh; collector Mostafa Sharaf
Forms with very short stout erect hairs on head and alitrunk; similar but slightly longer stout hairs on the gaster; alitrunk with coarse reticulo-pucnturation contrasting with a shiny near black gaster
	exoleta type worker, casent0906138, from Nigeria
	exoleta type worker, Gabon 97 - Pongara National Park, collector Yves Braet; Edge of savannah (BJ); 8.viii. 3006
	Ghana 06G0036 - collector Sky Stephens; May-August 2006; Treatment 3
	Ghana 06G0090 - collector Sky Stephens; May-August 2006; Forest Reserve
Forms with erect hairs on head and alitrunk moderately long and fine	.
	Cameroun; Matomb; 3°49' 0 N 11°4'0"E; highland area elevation >500m; Tuna bait in fallow; 26.vii.2007 (fk tetramorium sp L); coll. A Fotso Kuate.
	Gabon 125 - Pongara National Park, collector Yves Braet;
	Gabon 169 - Pongara National Park, collector Yves Braet; Pongara base (WF; series 2) 8.vi-20.vi.2006
	Gabon 189 - Pongara National Park, collector Yves Braet; Leaf litter (WF, series 2) 17-22.v.2006
	Gabon 231 ; Pongara National Park, collector Yves Braet; Leaf litter (WF) 27.vi-10.vii.2006
	Congo - Brazzaville, collection t 1.8; 19.viii.2007; pitfall trapped by Yves Braet & Eric Zassi.
	Tanzania - West Usambara Mts, Lushoto District, Grant's Lodge; Mkusu R., 3-4 km upstream of Kifungilo; 1660 m; 2 specimens; 03-08.x.2002; collected by Vasily Grebennikov
Tetramorium caldarium - narrow-headed - maximum separation of frontal carinae about equal to or > 0.5 HW	Bolton (1980) cites all New World and most Old World examples
	Bolton (1979) - his description seems at odds with the facts and his drawing- he states the frontal carinae are best developed to the posterior of the eye than they become weak or broken of fade out; and, the scrobes are feeble.
	Germany - Syntype, CASENT0102333, det. B Bolton; http://www.antweb.org/specimen.do?name=casentcasent0102333&shot=p1&project=.
	Tanzania - Mkomazi 3_50_05; collector G McGavin; three findings of 1-2 specimens each; two on Acacia nilotica (Trees 5/56 & 5/63); and one on Three findings of 1-2 specimens each; two on Acacia nilotica (Trees 5/56 & 5/63); and one on Heywoodia lucens (Tree 3/50)(Tree 3/50)
	Congo - Brazzaville, t 1.15; pitfall trap; collectors Yves Braet & Eric Zassi
T. caldarium broad-headed - maximum separation of frontal carinae < 0.5 HW	Bolton (1980) cites Kenya & India
	Saudi Arabia - collector Mostafa Sharaf
	Egypt - Kaseh; collector Mostafa Sharaf
Tetramorium amaniensis new species	The scapes and hind tibia have abundant short semi-erect pilosity; the alitrunk dorsum is not laterally marginate
	Tanzania - Zigi Lodge; Amani Nature Reserve; S 5°05' E 38°38'; 2200 m; Vasily Grebennikov, 9-11.x.2002; specimens collected also from two other locations