Tetramorium angulinode Santschi

Type location Congo (Tetramorium (Xyphomyrmex) angulinode n. sp., Santschi, 1910c: 385, illustrated, all forms) collected at Brazzaville, by A. Weiss - see below
junior synonyms
daphnis (Xiphomyrmex angulinode Sants v Daphnis n. var, Santschi, 1920b: 16, illustrated, worker & queen) from Zimbabwe, Hillside, Bulawayo, G Arnold - see http://www.antweb.org/specimenImages.do?name=casent0901163
humerosum (Tetramorium humerosum, Emery, in litteris, Bernard, 1952: 13, illustrated, worker & queen) from Cameroun, collector L. Conradt, 1895 - queen see http://www.antweb.org/specimenImages.do?code=casent0914276
papyri (Xiphomyrmex papyri spec. nov., Weber, 1943c: 374, illustrated, queen) from South Sudan, in the Sudd while on a river steamer - no images on Antweb (April 2015).
(see Bolton, 1995) .

Santschi's (1910c) description is at and . Santschi's (1920b) description of daphnis is at . Arnold (1926: 279) gave a fuller description of daphnis, this is at . Weber's (1943c) description of the papyri queen is at . Bernard's (1952) description of humerosum is at - Bolton pointed out that this largely describes a specimen of ataxium, whereas the type specimens were what Bolton decided was angulinode. Bolton's modern description (1980) is at .

The form named as nullispinum from Nigeria (Bolton, 1980: 241, worker) appears in Bolton's Catalogue, without any supporting details, as synonymised under angulinode (Bolton, 1995: 412, "new synonymy"). From Bolton's original description this appears to be incorrect and I have kept Tetramorium nullispinum separate.

The definitive angulinode, according to Bolton (1980) is a widespread but seemingly uncommon species usually inhabiting savannah or grassland, usually nesting amongst the roots of grasses and low plants. Interestingly, in view of the foregoing, Bernard (1952) listed the finding of a queen of "Xyphomyrmex angulinodis" from the Kéoulenta savanna; this seems to have passed unnoticed by Bolton (1980).

From Nigeria Bolton listed findings at CRIN (himself), and also from Mokwa (C. Longhurst) and IITA (B.R. Critchley), but he did not list my specimens, which I found at CRIN nesting in the ground and the drive area of a domestic garden (my 1980 CRIN Research Bulletin report as Xiphomyrmex T¹, deposited in the British Museum in 1976). Ghana records from Bolgatanga (P.M. Room) and the Agricultural Station, Pokoase (W. Belfield; misspelt by Bolton, 1980). Otherwise known from scattered locations throughout sub-Saharan Africa. Forel (1911f) reported angulinode from Zaïre, Kinshasa [Leopoldville] by Dr Dubois.

Bolton's (1980) list included Cameroun and he explained that the specimens were those discovered among the Forel collection in Geneva and bearing a label "humerosum Em." by Bernard (1952). Bernard himself decribed how he had specimens collected from Mt. Nimba which he could not identify. Then he came across the "humerosum" with the label by Emery but which Emery had not published and he (Bernard) did not know if there were others in the collection in Bologna. As Bolton related, the description, with illustration, given by Bernard is clear but does not match the Emery-labelled specimen. The availability of Antweb images (uploaded 20.ii.2014) of the Bernard-Mt Nimba specimens showed that I misunderstood what Bolton wrote.  To correct that: the Emery material (from Cameroun, collected by Conradt) is angulinode and the Mt. Nimba material is workers of Tetramorium ataxium.

There is a clear discrepancy between the drawings, both in the first publication and later, given by Santschi (1910c, 1920b) and that given by Bolton (1980).

Bolton, in common with all his works, gave no source for the depicted specimen. In this instance, he did not refer specifically to Santschi's description or figure. The Bolton drawing matched my earlier drawing of specimens I saw in Nigeria, and the illustration given by Weber (1943c) of the pedicel of the queen of his new species Xiphomyrmex papyri.

The Santschi type form also has quite abundant moderately long fine erect hairs all over, whereas, the papyri (Bolton) form has sparser, short, thick erect hairs on the head and alitrunk. The sculpturation on the head of the type form is of fine and densely packed longitudinal striations, wheras, the papyri form has coarser and much less densely packed longitudinal striations.

With the release on Antweb of photographs of the holotype, below, it is clear that Bolton's illusttration was not of the type form.

The photomontage of the holotype worker is collated from http://www.antweb.org/specimen.do?name=zfmkhym20096255.

Oxford University Museum specimens

Tetramorium angulinode B Taylor det.	Senegal Tambacounda B Ndiaye	13.viii.2009 Bambaraya 13°06'30"N 12°05'18" W	Bambaraya13-VIII-09 St 4 P4F Soudanian savannah, pitfall traps	2
Tetramorium angulinode B Taylor det.	Senegal Tambacounda B Ndiaye	13.v.2009 Bangouraya 13°05'02" N 12°08'01" W	Bangouraya 13-V-09 St 10 P1F Soudanian savannah, pitfall traps	1
Tetramorium angulinode B Taylor det.	Senegal Ferlo B Ndiaye	x.2010 Katané 15.48° N 14.08° W	Katané X 2010 T3P9 Sahelian savannah, pitfall traps	4
Tetramorium angulinode B Taylor det. Type form	Senegal Lamine Diamé 40	08.v.2012 Thiés 14°45'N 17°03'W	Pout V11 pitfall 2 tube 04	2
Tetramorium angulinode B Taylor det.	Benin J-F Vayssieres RVA 3040.6	20.ii.2013 Koro 09°22'21'' N 02°40'13'' E	Mangifera indica orchard prey of Oecophylla longinoda 1000-1100 h	1
Tetramorium angulinode B Taylor det.	Cameroun A Fotso Kuate Tetramorium sp1	10.v.2007 Awae II 03°54'30" N 11°25'58"	Pitfall in fallow	1
Tetramorium angulinode B Taylor det.	Cameroun A Fotso Kuate Tetramorium spD	29.ix.2007 Boga 03°54'30" N 11°25'58"	Quadrat in fallow	1
Tetramorium angulinode B Taylor det.	Cameroun A Fotso Kuate Tetramorium sp19	16.i.2008 Awae II 03°54'30" N 11°25'58"	Quadrat in forest	1
Tetramorium angulinode B Taylor det.	Central African Republic P Annoyer Di on reduviid	20.i.2005 Dzanga-Sangha 03°55’13.2" N 16°36’46.1" E	536m; U.V : 2h-6h, après Sefka (entre Bambio et croisement Nola/Berberati), dans layon forestier; from on a reduviid bug; collected in forest, 1st hour of the morning	2
Tetramorium angulinode B Taylor det.	Congo E Zassi 17-t-1	4-5.ii.2008 Lésio-Louna 03°20'12.0" S 015°28'43.6" E	Village Mah; 24h pitfall trap	1
Tetramorium angulinode Gabon 187 form B Taylor det.	Gabon Y Braet Gabon 187	17-22.v.2006 Pongara 00°34' N 09°19' E	Leaf litter, winkler funnel	1

The answer may lie in Santschi's style of designating varieties and "stirps" rather than new species for forms with somewhat similar overall morphology. The illustration from Santschi (1920b) is a good example. Both Santschi's own description of the type and Arnold's description of daphnis, are matched by the specimens I have from the Central African Republic and Congo.

More detailed photomontages of these can be seen on the linked page - T. angulinode type form.

TL ca 3.30 mm, HL 0.75, HW 0.65, CI 87, SL 0.42, SI 65, PW 0.58

Tetramorium papyri Weber ?

Type location South Sudan (Xiphomyrmex papyri, Weber, 1943c: 374, illustrated, queen) from on a ship in the Sudd, Upper White Nile, 8.vii.1939.

Weber's (1943c) description of the papyri queen is at . Bolton's modern description (1980) is at .

Nigeria specimens (as Xiphomyrmex species T¹, Taylor, 1980a: 63). WORKER. TL 2.24 mm, HL 0.56, HW 0.50, CI = 89, SL 0.34, SI = 68, PW 0.40. This has the quite narrow petiole profile, much finer sculpturation and a generally pale yellow-brown colour with the gaster darker. Head, dorsal alitrunk and pedicel rugoreticulate; lateral alitrunk punctate. Erect hairs moderately abundant and long. Antennal scrobes defined only as extensions of the frontal carinae. Propodeal spines moderately long and broad; metapleural lobes short, triangular. Petiole with vertical anterior and posterior faces; dorsum short, slightly convex; subpetiolar tooth acutely triangular.
Found at the Cocoa Research Institute of Nigeria, Idi Ayunre, nesting in the ground and the drive area of a domestic garden, collector B Taylor, 1976. Not listed by Bolton (1980), although deposited with him by me in 1976.

Photomontages of this form from Congo can be seen on the linked page - T. angulinode Santschi papyri Weber.

Photomontages of a similar but darker form from Gabon also can be seen on the linked page .