Tetraponera hespera , Ward, P. S., 2009

Ward, P. S., 2009, The ant genus Tetraponera in the Afrotropical region: the T. grandidieri group (Hymenoptera: Formicidae)., Journal of Hymenoptera Research 18, pp. 285-304: 295-296

publication ID

22935

publication LSID

lsid:zoobank.org:pub:6DA472F2-474A-4C92-81C7-7AA53E220E3B

persistent identifier

http://treatment.plazi.org/id/38584359-036C-4CEC-A96A-54E0010E7451

taxon LSID

lsid:zoobank.org:act:38584359-036C-4CEC-A96A-54E0010E7451

treatment provided by

Donat

scientific name

Tetraponera hespera
status

sp. n.

Tetraponera hespera  HNS  sp. n.

(Figs 2-4, 6, 9-12, 24)

Tetraponera  HNS  pswllO; Fisher 2002: 318. Cited in faunal inventory.

Holotype worker. MADAGASCAR Antsiranana : Nosy Be , 4 km ESE Andoany (= Hellville ), 100 m, 13°25'S 48°18'E, 2.v.1989, ex rotten stick on ground, rainforest, P. S. Ward # 10457 ( CASENT0012865) ( CASC). 

Paratypes. Séries of workers and queens, same locality and date as holotype, elevation 100-200 m (P. S. Ward#10456, 10457, 10459, 10463, 10465, 10470-1) ( BMNH, CASC, MCZC, PSWC, SAMC, UCDC)  .

Material Examined.-( BMNH, CASC, MCZC, PSWC, SAMC, UCDC) MADAGASCAR Antsiranana: Ampasindava, Ambilanivy, 3.9 km 181° S Ambaliha, 600 m (Fisher, B. L.; et al.)  ; Forêt Antsahabe, 11.4 km 275° W Dairana, 550 m (Fisher, B. L.; et al.)  ; Forêt Binara, 9.1 km 233° SW Dairana, 650-800 m (Fisher, B. L.)  ; Nosy Be, 4 km ESE Andoany (=Hellville), 100 m (Ward, P. S.)  ; Rés. Ankarana, 7 km SE Matsaborimanga, 150 m (Ward, P. S.)  ; Rés. Spéc. Ankarana, 13.6 km 192° SSW Anivorano Nord, 210 m (Alpert, G. D.; et al.)  ; Rés. Spéc. Ankarana, 13.6 km 192° SSW Anivorano Nord, 210 m (Fisher, B. L.; et al.)  ; Rés. Spéc. Ankarana, 22.9 km 224° SW Anivorano Nord, 80 m (Fisher, B. L.; et al)  ; R.S. Manongarivo, 10.8 km 229° SW Antanambao, 400 m (Fisher, B. L.)  ; R.S. Manongarivo, 12.8 km 228° SW Antanambao, 780 m (Fisher, B. L.)  ; Toliara: Ambohijanahary, 34.6 km 314° NW Ambaravaranala, 1100 m (Fisher, В. L.; et al)  ; Ambohijanahary, 35.2 km 312° NW Ambaravaranala, 1050 m (Fisher, B. L.; et al.)  .

Worker measurements (n = 13). HW 0.95-1.31, HL 1.19-1.55, LHT 1.12-1.53, CI 0.78-0.90, FCI 0.14-0.18, REL 0.30-0.35, REL2 0.35-0.41, SI 0.77-0.83, FI 0.29-0.34, PLI 0.50-0.58, PWI 0.42-0.53.

Worker diagnosis. Similar to T. grandidieri  HNS  (q.v.). Basal margin of mandible lacking tooth; anterior clypeal margin broadly convex and crenulate, directed forward; head relatively elongate (CI 0.78-0.90); metanotal spiracle visible in lateral view of mesosoma (Fig. 6); dorsal face of propodeum usually broadly convex in posterior view, but more dorsally compressed and subtriangular in one population(see below); standing pilosity and appressed pubescence generally sparse; integument mostly sublucid, with fine coriarious/puncticulate sculpture; body unicolorous yellow-brown or orange-brown, legs usually with contrasting black bands on the distal portions of the femora; banding sometimes weakly developed on the profemur, and absent from ali legs in one population.

Comments. T. hespera représente an assemblage of variably isolated populations in northwestern Madagascar. This species is most readily recognized by its distinctive color pattern: workers are usually a unicolorous yellow-brown or orange-brown, with contrasting black bands on the legs (Fig. 10). In earlier identifications of muséum material I employed a code name for this species: Tetraponera  HNS  pswllO.

The hespera-like population occupying the Ankarana Massif is divergent in several respects: workers lack the characteristic black leg banding (Fig. 12) and they have a dorsally narrowed propodeum that appears more or less triangular in shape when seen in posterior view (Fig. 3), in contrast to the broadly convex propodeum seen in other populations of T. hespera  HNS  (Fig. 4) and in the rest of the T. grandidieri  HNS  group. Although I considered treating the Ankarana form as a different species, severa! observations argued against this.

(1) It is strictly allopatric to the more typical morph of Г. hespera  HNS  , so there is no "test" of species distinctness in sympatry.

(2) Samples from tropical dry forest at Forêt Antsahabe, 60 km southeast of Ankarana, have black leg banding but the propodeum tends to be intermediate in shape between the Ankarana morph and more typical T. hespera  HNS  . (3) A worker ( BLF 10881; CASENT0053718) from another nearby locality, Forêt Binara, has black leg banding and a broadly convex propodeal dorsum -yet it is genetically identical at the mitochondrial COI locus to a worker from Forêt Antsahabe. The COI data indicate that ali three populations (Ankarana, Antsahabe and Binara) are closely related and form a clade that is sister to T. hespera  HNS  + T. hirsuta  HNS  , but with combined nuclear gene séquences the three populations do not form a clade; instead, they are paraphyletic with respect to T. hirsuta  HNS  . Thus, recognizing the Ankarana form as a distinct species would require an arbitrary division along a gradient of differentiated allopatric populations.

Distribution and biology. This species is found in northwestern Madagascar, with an isolated population at Ambohijanahary in centrai western Madagascar (Fig. 24). It occurs sympatrically with T. grandidieri,  HNS  T. hirsuta  HNS  and T. merita  HNS  at one or more localities. Most populations of T. hespera  HNS  are in seasonally dry rainforest, where colonies tend to nest near the ground level, usually in rotten sticks. One colony from the type locality ( PSW 10456) was nesting in an earthworm cast on the ground. As in T. grandidieri  HNS  , observed colony sizes are small (4-36 workers).

CASC

USA, California, San Francisco, California Academy of Sciences

BMNH

United Kingdom, London, The Natural History Museum [formerly British Museum (Natural History)]

MCZC

USA, Massachusetts, Cambridge, Harvard University, Museum of Comparative Zoology

PSWC

PSWC

SAMC

South Africa, Cape Town, Iziko Museum of Capetown (formerly South African Museum)

UCDC

USA, California, Davis, University of California, R.M. Bohart Museum of Entomology

BLF

BLF

PSW

PSW