A taxonomic revision of the Neotropical myrmicine ant genus Lachnomyrmex Wheeler (Hymenoptera: Formicidae)
Feitosa, R. M.
Brandão, C. R. F.
Zootaxa
2008
1890
1
49
urn:lsid:biosci.ohio-state.edu:osuc_concepts:245575
Insecta
Formicidae
Lachnomyrmex
CoL
Animalia
Lachnomyrmex amazonicus Feitosa & Brandão
Hymenoptera
11
Arthropoda
species
amazonicus
Figures 2, 20
Holotypeworker. BRAZIL: Para: Parauapebas, Fl. Nacional de Carajas, Garagem, 06°02'54"S 50°04'55''W, 25.iv - 02.v.2008, Rogerio R. Silvacol., no. 5 [ MZSP]. Paratypes. same data as holotype, no. 1 (1 worker) [ CASC]; same data, no. 4 (1 worker) [ CPDC]; same data (1 worker) [ ICNC]; same data, no. 5 (1 worker) [ USNM]; same data (1 worker) [ WMPC]; same data, nos. 1/2/3/4/5 (5 workers and 3 gynes) [ MZSP]; BRAZIL: Amazonas: Manaus, 22.ix.1993, A.B. Casimirocol., no. 4829 (1 worker) [ INPA]; iii - iv.1994, R. Didhamcol. (3 workers) [ BMNH]; same data (1 worker) [ MZSP]; Mato Grosso: Alta Floresta, 10°47'S 56°49'W, 28.iv.1999, H.L. Vasconceloscol. (1 worker) [ INPA]; Para: Melgaco, Caxiuana, 1°44'9"S 51°29'15"W, 27-29.i.2003, A.Y. Harada, E.P. Fagundes, P. Batra, R. Calisto& Mocols, no. 5 [ MPEG]; 1°45'15"S 51°31'20"W, 23-25.i.2004, A.Y. Harada, E. P. Fagundes, R. Calisto & Mocols, no. 5 (1 worker) [ MZSP]; Parauapebas, Fl. Nacional de Carajas, Casa de Hospedes, 06°03'41''S 50°03'13"W, 25.iv - 02.v.2008, Rogerio R. Silvacol., no. 1 (1 worker) [ MZSP]; Nucleo Urbano, 06°03'53''S 50°03'42''W, 25.iv - 02.v.2008, Rogerio R. Silvacol., no. 1 (1 worker) [ MZSP]; Zoobotanico, 06°03'41''S 50°03'13''W, 25.iv - 02.v.2008, Rogerio R. Silvacol., no. 1 (1 worker) [ MZSP].
FIGURE2. Paratypeworker of Lachnomyrmex amazonicusfrom Para, Brazil: A, head in full face view; B, lateral view; C, dorsal view. Image by Michele Esposito, specimen CASENT0173882.
Worker diagnosis. Body irregularly rugose; promesonotum in profile elevated well above the level of propodeum; metanotal groove weakly impressed to obsolete; propodeal spines slightly directed upwards; teeth of propodeal lobes reduced; dorsum of postpetiole with more than 10 long, flexuous hairs; first gastral tergite entirely devoid of long hairs.
Holotypemeasurements. HL 0.58; HW 0.58; ML 0.16; SL 0.31; EL 0.11; WL 0.66; PSL 0.14; PL 0.28; PPL 0.13; GL 0.76; TL 2.57; CI 100; SI 54; OI 18. Worker measurements (n=6). HL 0.52-0.66; HW 0.54-0.66; ML 0.16-0.21; SL 0.31-0.41; EL 0.08- 0.13; WL 0.57-0.74; PSL 0.11-0.17; PL 0.22-0.29; PPL 0.12-0.15; GL 0.68-0.82; TL 2.26-2.84; CI 100- 103; SI 50-63; OI 13-19. Worker description. Color dark reddish-brown to blackish, with waist and gaster slightly lighter; appendages yellowish to light brown. Body densely covered by vermiculate short rugae, forming irregular areolae on promesonotum; rugae somewhat longer and longitudinal on head dorsum, and slightly sparser on mesopleura and lateral surfaces of propodeum; mandibles with short longitudinal striae restricted to basal portion; petiole and postpetiole finely and irregularly rugose. Abundant pilosity on head and mesosoma dorsum; dorsum of petiolar node and postpetiole each with more than 10 long, flexuous hairs; first gastral tergite entirely devoid of long hairs. Head as long as broad, with vertexal margin weakly convex; frontal lobes laterally rounded; eyes with about seven facets on maximum diameter. Promesonotum strongly convex in profile, elevated well above the level of propodeum; metanotal groove shallow to virtually obsolete; propodeal spines slightly directed upwards; teeth of propodeal lobes reduced, with around one-third of propodeal spines length. Petiolar node moderately elevated, dorsally rounded, and with the posterior face weakly sloped in lateral view; postpetiole feebly convex dorsally and without ventral processes. Gyne. Differing from worker by the larger eyes, with around 14 facets at maximum diameter; propodeal spines straight, without the apexes curved upwards.
Etymology. The name refers to the region from where this species is known, the Amazon Basin.
Comments. The general habitus of this species allies it with Lachnomyrmex longinoi, L. nordestinus, L. plaumanni, and L. victori. These species share the irregular body sculpturation, the obsolete metanotal groove, and the absence of long hairs on the first tergite of gaster. However, L. amazonicuscan be distinguished from these species by the combination of promesonotum strongly convex, propodeal spines directed upwards, and dorsum of postpetiole bearing more than 10 long hairs.
Lachnomyrmex amazonicusis known from Amazonian Brazil, in 60-200melevation rainforest. It is one of the few species in the genus occurring in lowland forests rather than in submontane localities. All records refer to workers obtained in samples of sifted litter from the forest floor.
1416638460
2008-04-25
2008-05-02
2008-04-25
MZSP
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
Holotype
1416638456
2008-05-02
2008-05-02
2008-04-25
CASC
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
Paratypes
1416638455
2008-05-02
2008-05-02
2008-04-25
CPDC
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
1416638467
2008-05-02
2008-05-02
2008-04-25
ICNC
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
1416638469
2008-05-02
2008-05-02
2008-04-25
USNM
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
1416638449
2008-05-02
2008-05-02
2008-04-25
WMPC
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
1416638446
2008-05-02
2008-05-02
2008-04-25
MZSP
Brazil
-6.048333
Fl. Nacional de Carajas
1
-50.081944
Parauapebas
Para
1416638451
1993-09-22
INPA
A. B. Casimiro
Brazil
Manaus
Manaus
Amazonas
1416638461
1994-03
1994-04-31
1994-03
BMNH
R. Didham
Brazil
Manaus
Manaus
Amazonas
1416638447
1994-03
1994-04-31
1994-03
MZSP
R. Didham
Brazil
Manaus
Manaus
Amazonas
1416638453
1999-04-28
INPA
H. L. Vasconcelos
Brazil
-10.783334
Alta Floresta
1
-56.816666
Mato Grosso
1416638454
2003-01-27
2003-01-29
2003-01-27
MPEG
A. Y. Harada, E. P. Fagundes, P. Batra, R. Calisto & Mo
Brazil
-1.7358334
Caxiuana
1
-51.4875
Melgaco
Para
1416638458
2004-01-23
2004-01-25
2004-01-23
MZSP
A. Y. Harada, E. P. Fagundes, R. Calisto & Mo
Brazil
-1.7541667
Caxiuana
1
-51.52222
Melgaco
Para
1416638471
2008-04-25
2008-05-02
2008-04-25
MZSP
Brazil
-6.061389
Fl. Nacional de Carajas
1
-50.05361
Parauapebas
Para
1416638459
2008-04-25
2008-05-02
2008-04-25
MZSP
Brazil
-6.0647225
Rogerio R. Silva
1
-50.061665
Nucleo Urbano
Para
1416638440
2008-04-25
2008-05-02
2008-04-25
MZSP
Brazil
-6.061389
Rogerio R. Silva
1
-50.05361
Zoobotanico
Para