Tetramorium boltoni

Tetramorium boltoni
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Crematogastrini
Genus:	Tetramorium
Species:	T. boltoni
Binomial name
	Tetramorium boltoni; Hita Garcia, Fischer & Peters, 2010 Specimen Label

Tetramorium boltoni is a widely distributed and very common rain forest species.

Identification

Tetramorium boltoni can be best distinguished from other members of the species complex by the following character combination: SI 71 - 78; propodeal spines moderately sized to long (PSLI 23 - 29), elongate-triangular with a broad base to spinose; head and mesosoma strongly longitudinally rugose, ground sculpturation generally reduced, smooth and shiny; standing hairs present on first gastral tergite; coloration uniformly very dark brown to black.

A member of the Afrotropical weitzeckeri species complex, which is part of the weitzeckeri species group.

Keys including this Species

Distribution

Nigeria to Western Kenya and from Sudan to Angola. Known from Angola, Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea, Gabon, Kenya, Nigeria, Uganda and Sudan

Latitudinal Distribution Pattern

Latitudinal Range: 3.362777778° to -10.01058°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps

Distribution based on Regional Taxon Lists

Afrotropical Region: Cameroun, Central African Republic, Congo, Democratic Republic of Congo, Gabon, Kenya (type locality), Uganda, United Republic of Tanzania.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Habitat

Rainforest

Biology

Castes

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

boltoni. Tetramorium boltoni Hita Garcia, Fischer & Peters, 2010b: 66, figs. 10A, 11B, 16B, 17B, 18B, 76-78 (w.) KENYA.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

This species was previously identified as Tetramorium weitzeckeri but it is clearly distinctive based on its morphology, habitat preference, and biogeography. Tetramorium boltoni is generally significantly smaller in size (HW 0.644 - 0.744, SL 0.467 - 0.539, PW 0.489 - 0.561, WL 0.778 - 0.911) compared to T. weitzeckeri (HW 0.772 - 0.933, SL 0.789 - 0.944, PW 0.578 - 0.711, WL 0.911 - 1.206). Additionally, several body parts, such as the antennal scapes and the propodeal spines, are distinctly less strongly developed in T. boltoni (SI 71 - 78, PSLI 23 -29) than in T. weitzeckeri (SI 77 - 83, PSLI 32 - 45). Furthermore, T. boltoni is a strict forest species inhabiting the leaf litter stratum of Equatorial rain forests while T. weitzeckeri prefers open habitats in Eastern or Southern Africa. The differentiation of T. boltoni from Tetramorium snellingi is easier since T. snellingi is smaller, distinctly bicoloured and possesses smaller propodeal spines (PSLI 17 - 22). In addition, T. boltoni cannot be confused with the morphologically close Tetramorium renae since this species is usually bicoloured, with the gaster of lighter colour than the mesosoma, and shows a high grade of reduction in mesosomal sculpturation. Also Tetramorium guineense with its conspicuous, strong and dense reticulate-punctate ground sculpture on the head and the longer propodeal spines (PSLI 28 - 43) can be simply separated from T. boltoni. The remaining species of the weitzeckeri complex differ from T. boltoni by their absence of standing hairs on the first gastral tergite.

Description

Worker

HL 0.678 - 0.761 (0.717); HW 0.644 - 0.744 (0.686); SL 0.467 - 0.539 (0.513); EL 0.144 - 0.167 (0.155); PW 0.489 - 0.561 (0.523); WL 0.778 - 0.956 (0.843); PSL 0.167 - 0.217 (0.186); PTL 0.100 - 0.128 (0.112); PTH 0.289 - 0.339 (0.313); PTW 0.256 - 0.306 (0.275); PPL 0.144 - 0.200 (0.176); PPH 0.267 - 0.333 (0.298); PPW 0.289 - 0.356 (0.320); CI 92 - 100 (96); SI 71 - 79 (75); OI 21 - 24 (22); PSLI 23 - 29 (26); PeNI 48 - 60 (53); LPeI 31 - 40 (36); DPeI 226 - 267 (245); PpNI 55 - 65 (61); LPpI 52 - 67 (59); DPpI 167 - 200 (182); PPI 105 - 125 (117) (47 measured).

Head slightly longer than wide, sometimes as long as wide (CI 92 - 100). Anterior clypeal margin distinctly medially impressed. Frontal carinae strongly developed, becoming weaker behind level of eye and ending shortly before posterior margin of head. Antennal scrobe narrow, shallow, and without defined ventral margin, ending before posterior margin of head. Antennal scape of medium length (SI 71 - 79). Eyes relatively small to moderate (OI 21 -24), with 7 to 9 ommatidia in longest row. Metanotal groove impressed. Propodeal spines long (PSLI 23 - 29), elongate-triangular to spinose with broad base and acute apex. Propodeal lobes small, elongate-triangular and acute. Node of petiole squamiform, in dorsal view more than 2 times wider than long (DPeI 226 - 260) and in profile 2.5 to 3.2 times higher than long (LPeI 32 - 40). Postpetiole in dorsal view distinctly wider than long (DPpI 167 - 200) and much more voluminous than petiole. In lateral view postpetiole weakly to moderately squamiform and thicker compared to petiole, only slightly antero-posteriorly compressed, between 1.5 to 1.9 times higher than long (LPpI 52 - 67). Mandibles distinctly longitudinally striate. Clypeus usually with 3 to 5 longitudinal rugae, median ruga always strongly developed and unbroken, while lateral rugae variable. Head longitudinally rugose with widely spaced rugae, dorsum usually with 7 to 10 longitudinal rugae between frontal carinae, almost all running unbroken to posterior margin of head. Spaces between rugae with very weak, nearly effaced ground sculpture or completely unsculptured, generally shiny. Scrobal area with reduced punctate ground sculpture or unsculptured. Mesosoma dorsally and laterally with coarse, mostly longitudinal, widely spaced rugulation. Spaces between rugae and propodeal declivity unsculptured, smooth and shiny. Petiole, postpetiole and gaster completely unsculptured, smooth and shiny. All dorsal surfaces of head, mesosoma, both waist segments and gaster with abundant, long, fine, and simple suberect to erect hairs. Fine pubescence on tibiae appressed, on antennal scapes appressed to decumbent. Head, mesosoma, petiole, postpetiole, and gaster uniformly very dark brown to black, appendages often of lighter colour.

Type Material

Holotype worker, KENYA, Western Province, Kakamega Forest, Salazar, Transect 6, 00° 19' 36 N, 34° 52' 14.6 E, 1650m, 21.VI.2007, Kakamega 2007 survey, primary rain forest, pitfall trap, leg. M. Peters (National Museum of Kenya - ZFMK_HYM_2009_6145). Paratypes, 40 workers with same data as holotype (The Natural History Museum: 8 workers ZFMK_HYM_2009_6163, ZFMK_HYM_2009_6164, ZFMK_HYM_2009_6165, ZFMK_HYM_2009_6166, ZFMK_HYM_2009_6167; California Academy of Sciences: 6 workers ZFMK_HYM_2009_6248, ZFMK_HYM_2009_6249, ZFMK_HYM_2009_6250; Field Museum of Natural History: 1 worker ZFMK_HYM_2009_6251; Los Angeles County Museum of Natural History: 1 worker ZFMK_HYM_2009_6252; Musee d'Histoire Naturelle Genève: 2 workers ZFMK_HYM_2009_6149, ZFMK_HYM_2009_6150; Naturhistorisches Museum, Basel: 2 workers ZFMK_HYM_2009_6254; NMK: 3 workers ZFMK_HYM_2009_6146, ZFMK_HYM_2009_6147, ZFMK_HYM_2009_6148; South African Museum: 1 worker ZFMK_HYM_2009_6253; Zoologisches Forschungsinstitut und Museum Alexander König: 16 workers ZFMK_HYM_2009_6151, ZFMK_HYM_2009_6152, ZFMK_HYM_2009_6153, ZFMK_HYM_2009_6154, ZFMK_HYM_2009_6155, ZFMK_HYM_2009_6156, ZFMK_HYM_2009_6157, ZFMK_HYM_2009_6158, ZFMK_HYM_2009_6159, ZFMK_HYM_2009_6161, ZFMK_HYM_2009_6162, ZFMK_HYM_2009_6168, ZFMK_HYM_2009_6169, ZFMK_HYM_2009_6170, ZFMK_HYM_2009_6171).

Etymology

The new species is dedicated to Barry Bolton, Isle of Wight, United Kingdom, to honour his lifetime dedication on myrmecology. Most actual taxonomic and systematic works would not be possible without his fundamental publications of the last decades.

References

Hita Garcia, F.; Fischer, G.; Peters, M. K. 2010. Taxonomy of the Tetramorium weitzeckeri species group (Hymenoptera: Formicidae) in the Afrotropical zoogeographical region. Zootaxa 2704:1-90.
Mbenoun Masse, P.S., Ebolo, G.L.M., Titti, G.E., Mony, R. 2021. Ant species richness, abundance and functional groups along an elevation gradient in Central Cameroon. Biodiversity Journal 12(1): 179-194 (doi:10.31396/biodiv.jour.2021.12.1.179.194).

References based on Global Ant Biodiversity Informatics

Garcia F.H., Wiesel E. and Fischer G. 2013.The Ants of Kenya (Hymenoptera: Formicidae)Faunal Overview, First Species Checklist, Bibliography, Accounts for All Genera, and Discussion on Taxonomy and Zoogeography. Journal of East African Natural History, 101(2): 127-222
Hita Garcia F., G. Fischer, and M. K. Peters. 2010. Taxonomy of the Tetramorium weitzeckeri species group (Hymenoptera: Formicidae) in the Afrotropical zoogeographical region. Zootaxa 2704: 1-90.
Hita Garcia F., and G. Fischer. 2014. Additions to the taxonomy of the Afrotropical Tetramorium weitzeckeri species complex (Hymenoptera, Formicidae, Myrmicinae), with the description of a new species from Kenya. European Journal of Taxonomy 90: 116.
IZIKO South Africa Museum Collection
Ross S. R. P. J., F. Hita Garcia, G. Fischer, and M. K. Peters. 2018. Selective logging intensity in an East African rain forest predicts reductions in ant diversity. Biotropica 1-11.