Smicromyrme (Astomyrme) matritensis ( Mercet, 1905 )

Matias, Rafael, 2024, The subgenus Astomyrme Schwartz, 1984 in the Iberian Peninsula: associating Physetopoda pusilla (Klug in Waltl, 1835) with Smicromyrme suberratus Invrea, 1957, and description of the hitherto unknown female of S. matritentis (Mercet, 1905) (Hymenoptera: Mutillidae), Zootaxa 5480 (1), pp. 1-62 : 33-43

Smicromyrme (Astomyrme) matritensis ( Mercet, 1905)

( Figs 12– 16 , 21E )

Mutilla Matritensis Mercet, 1905: 493 , ♂ (original description), type locality: Madrid ( Spain), “ Septiembre 1904 ”, Arias Encobet leg., holotype in Museo Nacional de Ciencias Naturales (MNCN, Madrid, Spain).

Smicromyrme matritensis : Giner Marí 1944: 86, ♂; Suárez 1954: 6 (discussed); Lelej 2002: 76 (catalogued); Pagliano et al. 2020: 198 (catalogued).

Smicromyrme (Astomyrme) matritensis : Matias 2023b: 78 (♂, key).

Diagnosis. MALE ( Figs 12A–K ). Recognized by the metasomal pattern of pubescence (silvery-white appressed pubescence forms medially enlarged apical band on T2 and full band over T3, also sparsely over T7), the unique structure of the mandible (lacks external tooth basally, apically tridentate) and wing venation (second transverse-cubital vein with spurious vein, forming “T”-shape). Body length 8 mm. FEMALE (hitherto unknown; Figs 13– 16 , 21E ). This form may resemble a member of the genus Physetopoda due to its pygidial shape. It can be recognized by the combination of very small inconspicuous scutellar scale with posteriorly adjacent fovea enlarged; pygidium elongated ovate, fully striated to apex or with poorly marked apex; mesosoma subrectangular with well marked humeral angle and subtruncate propodeum; conspicuous pubescence pattern (vertex with round spot of sparse golden pubescence; T2 dense silvery pubescence defining basally three oval spots, two lateral, one medial, and medially enlarged apical band; full band over T3; silvery setae margining pygidium); and mandible structure (apical tooth short and broad, with two internal denticles separated by gap wider than apical tooth length). Body length 6.2–7.0 mm.

Redescription. MALE ( Figs 12A–K ). Body length 8.0 mm. Colouration. Head black, except for mandible with subapical ferruginous-red band and dark ferruginous-red antennal tubercle; mandible basally covered with white pubescence; frons with white pubescence. Antenna dark-brown, the flagellum orange brown ventrally, and the scape apically, pedicel and F1 paler reddish-orange; scape with yellowish-white pubescence. Mesosoma ferruginous-red with sternum and propleura black; tegula ferruginous-red; mesoscutum with black pubescence. Wings slightly infuscate, darker apically outside the cells; veins dark-brown, basally yellowish. Legs yellowish-red with black coxae, covered with white pubescence; tibial spurs yellowish. Metasoma black, with silvery-white appressed pubescence forming medially enlarged apical band on T2 and full band over T3, and more sparsely over T7; S2–3 with fringe of sparse white pubescence; felt-line on T2 long and narrow, short on S2, composed of golden brown setae. Shape, structure and punctation. Head transverse, subrectangular with rounded posterior angles, slightly broader than pronotum; clypeus basally with very low medial carina, absent from the apical half, with medial apical triangle concave margined by two curved carinae ending in two weakly-defined tubercles with straight or slightly concave anterior margin; eye with weak internal notch; ocelli small, width of anterior ocellus similar to diameter of F1, POL = OOL; mandible apically tridentate, with external tooth absent but low tubercle present basoventrally. Antenna with pedicel ca. two-thirds of F1, F2 ca. twice as long as F1 and subequal to F3. Wings with veins notably thinner apically; radial cell apically sub-truncate; second tranverso-cubital vein “L” shaped with short spurious vein; pterostigma sub-celluliform with thickened vein and paler centre. Tibiae unarmed. T1 short and broad, ca. half as wide as T2. T2 maximum width 1.4 × T2 medial length. Genitalia ( Figs 12K–M ). Apex of penial valve projects beyond inner protuberance of gonostylus, reaching ca. 45% of distance of inner protuberance to apex (dorsal view); volsella basally approximately aligned (slightly posterior) with inner protuberance of gonostylus, apically longer than apex of penial valve; volsella basally subparallel sided, elongated, apicad narrowed and curved inwards, with very apex bent inwards (forming minute tubercle); volsella with dorsal margin asetose.

Description. FEMALE (hitherto unknown; Figs 13A–L ). Body length 6.5 mm. Colouration. Head black, except for dark reddish-brown antennal tubercle, ferruginous-yellow basal two thirds of mandible; mandible externo-basally with few pale brownish erect setae; vertex with well defined roundish spot of short (as long as over mesosomal dorsum), sparse, recumbent golden pubescence, posteriorly rounded and anteriorly weakly acute over frons; sparse black recumbent pubescence on frons, above the antennal scrobe carina and on rear vertex; vertex with sparse erect dark-brown setae, as long as the smaller eye diametre; clypeus with long pale yellowish-brown setae; lower gena and malar space with sparse silvery-white pubescence, denser towards mandible base; postgena glabrous. Antenna dark-brown, except for apically orange-brown scape, pedicel and F1, ventrally orange-brown pedicel and F1–5; scape with yellowish-white sparse pubescence, with minute setae over pedicel and F1. Palpi pale brown. Mesosoma dark ferruginous-red (including scutellar scale), except for black pronotal band (narrower laterad, not covering anterior angle dorsally) and spot on propodeal posterior face, and blackish-brown propleuron; mesosomal dorsum sparsely covered with golden recumbent pubescence (few black setae admixed posterolaterally), with finer sparse recumbent black pubescence on pronotum; short erect dark setae (as on head) sparsely over dorsum, somewhat longer on propodeum, and sparse longer yellowish-white erect setae laterally and on propodeum (where more numerous); sparse whitish recumbent pubescence on mesopleuron. Legs dark ferruginous-red, except procoxa blackish-brown, meso and metacoxa chestnut-brown basally, and profemur, meso and metafemora, meso and metatibiae distally weakly darker; legs with sparse long yellowish-white pubescence, shorter on tarsi; meso and metatibial external spines yellowish-brown, apically darker; meso and metatibial spurs translucent, pale yellowish-brown. Metasoma black except for dark ferruginous-red T1 (except narrow apical margin) and S1, and chestnut-brown T3–6 laterally and S3–6 basally; pubescence black and sparse (punctation visible), except for the following areas covered with dense silvery-golden appressed pubescence: T2 basally with three oval spots (one medial, two lateral, conspicuous in dorsal view), and apically with narrow dense band medially enlarged triangularly; T3 with full dense band weakly narrowed apicomedially; T4 with small tuft laterally; T6 with sparse long silvery-golden setae lateral to the pygidium; S2 covered with moderately sparse pale recumbent pubescence, which also forms apical fringes on S2–6; felt-line on T2 composed of tightly set short yellowish-brown to blackish setae (some silvery anteriorly), overlapped anteriorly by sparse whitish pubescence part of the basolateral spots; erect setae distributed sparsely over mesosomal dorsum, short and black over areas with black pubescence, paler brown and yellowish-white (both longer) over areas with silvery pubescence, denser and paler over T1. Shape, structure and punctation. Head. Head proportionately small, dorsally subrounded, with weakly convergent sides behind the eyes, poorly marked posterior angles, weakly convex posterior border, measured behind the eyes approximately as broad as pronotum. Eyes dorsally weakly prominent, head 1.05 × broader over the eyes than behind eyes. Frons and vertex densely punctate-reticulate, weakly shiny, punctures small round to suboval (smaller than on mesosomal dorsum), smaller on vertex; frons with weakly punctate medial line; narrow interspaces, some obliterate; gena densely, deeply punctate, punctures as large as on frons, narrow interspaces (some obliterate), lower gena with larger, flatter bottom, punctures; short occipital carina anteriorly. Sides of oral fossa almost straight, form angle of ca. 90º, with low hypostomal carina. Clypeus ( Fig. 13I ) short, subtruncate (dorsal view), microsculptured (dull), with sinuate medial transverse carina, anterolaterally with one small tubercle on each side of its margin; notable longitudinally elongate tubercle medially on upper half, projecting beyond clypeus edge in dorsal view; lower half short, bend posterad, weakly concave.Antennal scrobe densely, shallowly punctate, with weakly undulate dorsal carina. Mandible apically abraded in this specimen; apex short, internally with subapical denticle, and weakly developed low obtuse denticle approximately at half length of distal element, both denticles separated by distance longer than apical tooth; distal element externally straight. Antenna ( Fig. 13E ): pedicel 0.81 × F1, F1 subequal to F2 and 0.87 × F3. Mesosoma. Dorsally subrectangular; length of pronotal anterior border to scutellar scale ca. 0.95 × maximum mesosomal width; pronotal anterior border weakly convex, with subparallel pronotal sides, weakly narrowed behind pronotal spiracle and weakly convex propodeal sides; humeral angle well marked; propodeum with short dorsal face and subtruncate posterior face; mesosomal ratios (pronotal angle: pronotal spiracles: narrowest point: propodeum at scutellar scale level) are 89: 100: 90: 96. Humeral carina sharp, forming denticle apically at humeral angle. Dorsum and upper propodeal posterior face punctate to foveate-reticulate; interspaces narrow, some weakly raised and some obliterate; cell just posterior to scutellar scale enlarged. Scutellar scale ( Fig. 13L ) inconspicuous, notably small, basally less than one puncture wide, approximately as long as wide, protruding at an angle of ca. 50º, apically weakly rounded. Legs. Meso and metatibia externally with ca. nine short spines in two rows, and ca. three finer apical spines. Coxae punctate. Metasoma. T1 short, dorsal length ca. 0.17 × apical width. T2 basally narrow, with weak step from T1, maximum width ca. 2.3 × T1 apical width, and ca. 1.01 ×T2 medial length; densely punctate-reticulate, punctures small and most elongate (length up to ca. 2 × width), sparser between the basomedial spot of pale pubescence and the apical band; interspaces narrower than one puncture wide, not shiny. S1 with longitudinal medial carina. S2 densely punctate, punctures large over disc (small, dense apically), round to weakly elongate, interspaces weakly shiny ca. 2–3 punctures wide over disc and narrower elsewhere. S6 apically weakly bidentate. Pygidium elongate ovate, covered in divergent well marked parallel striae (also parallel to pygidium sides) defining concentrical arches, with poorly marked apex; laterally low carinate over the apical two thirds. Felt-line ca. 0.3 × T2 lateral length. Ratios of head width over eyes: head width behind eyes: pronotal anterior border: pronotal spiracles: mesosomal narrowest point: propodeum at scutellar scale level: T1 apical width: T2 maximum width are 69: 66: 65: 72: 66: 70: 46: 100.

Material examined (1♂, 4♀; all specimens R. Matias leg., det. & coll.). PORTUGAL. VILA REAL: Montalegre, Pitões das Júnias (41º51'47.07''N, 7º57'22.83''W), 1171 m, 24.v.2017, 1♀ . VISEU: Sernancelhe, Lamosa (40º52'53.49''N, 7º38'40.19''W), 783 m, 11.vi.2017, 1♀ . BEJA: Odemira, valey of ribeira do Torgal (37º38'20.51''N, 8º37'12.14''W), 14 m, 15.vii.2019, 1♂, 1♀ (allotype) . SPAIN. GALICIA: ORENSE, Baja Limia, Muiños, serra do Xurés: serra do Pisco (41º52'45.60''N, 7º56'18.10''W), 1245 m, 14.v.2019, 1♀ .

Intraspecific variation ( Figs 14–16 ). FEMALE (N = 3). Body length 6.2–7.0 mm. The three females collected in Northern Portugal and Spain ( Fig. 14 ) are broadly similar to the specimen from Southern Portugal (female allotype), described above, though notably lighter coloured on some structures. Differences are as follows, always compared with the allotype. Colouration. Antenna paler, reddish-brown. Mesosoma paler, light ferruginous-red; thin black pronotum band thus more contrasting; in the specimen from Galicia ( Fig. 14C ), spot of pale pubescence on vertex smaller ( Fig. 15A ) and narrow black pronotal band does not extend to humeral angle ( Fig. 15B ). Propleuron lighter, ferruginous-red. Legs paler, ferruginous-yellow, with femora and trochantera slightly darker reddish (distally darker); coxae darker ferruginous, with procoxa blackish; apical lobes of pro and metafemora articulations yellow. Metasoma darker, without brown tinge; S1 darker, blackish-brown. Shape and structure. Specimen from Galicia ( Figs 14C , 15 ) more robust than allotype and the other two specimens. Mandible not visibly abraded on two specimens, retaining full shape: apical tooth short and somewhat broad, the two internal denticles acute, separated by wide gap longer than apical tooth length (see Discussion for illustrated comparison of this feature with other Iberian Smicromyrmini : Fig. 21 ). Clypeus: anterolateral tubercles on medial transverse carina less noticeable on one specimen. Mesosomal length to scutellar scale 1.00–1.01 × maximum mesosomal width. Scutellar scale with similar structure and very small size, and even less conspicuous on the specimen from Pitões das Júnias. T2 with denser punctation over disc; T2 width ca. 0.92–0.98 × T2 medial length. Pygidium ( Fig. 16 ) with similar structure on all specimens, striations noticeable also over apex, except apicomedial weakly marked elongated area .

Distribution ( Figs 11C , 17 ). Iberian Peninsula: from central Spain (Madrid), northwest to southern Galicia and northern Portugal, south to southwest Portugal. See also ‘Additional data’, below.

Remarks. A) Sex-association. Both male and female were collected on the same dirt bank, within two minutes from each other; no other mutillids were recorded at this site. The male was first observed prospecting insistently, flying low, over an area of loose soil covered with dry grasses, before it was collected at 17:44 GMT; the female was found exactly two minutes later within the same section of the bank (within less than one metre from where the male was collected). Given the male was the first find of S. matritensis for Portugal (otherwise almost unknown) and the female represents an undescribed form, the simplest explanation seems the female to be the hitherto unknown female of the species; this association is further supported by structural features that place both insects in the same subgenus (see Discussion).

B) Behaviour. Period of activity: the specimen from Pitões das Júnias was collected during the morning, at 09:40 GMT, while the other specimens were found at 17:40 GMT (Galicia), 17:45 GMT (Lamosa) and 17:44/17:46 GMT (♂ / ♀, Ribeira do Torgal); this agrees with the behaviour of other mutillid wasps. The few records are comprehended between the 14 th May and the 24 th August.

C) Additional data. Further to the holotype, another S. matritensis specimen (not examined by the author) is deposited in the collection of the Museo Nacional de Ciencias Naturales ( MNCN), Madrid (D. Parejo-Pulido, pers. comm.): Sequeros , Salamanca / 24-VIII-1959 / F. Verges leg./ J. Suárez det. 1962 [ MNCN _ Ent 63065] .

One female of what seems to be this species has been photographed in Southern Spain: Parque Natural de Los Alcornocales, Cádiz (Andaluzia) , 29.iv.2016 (Gail Hamphire); these images are publicly available at an Internet (www) photography website (see Hampshire 2017); due to the unconfirmed nature of this record, it is not included in the distributional map.

Habitat. Diverse and broad, from mountainous areas under Atlantic influence (to 1245 m asl), including forested areas, to coastal lowlands with Mediterranean climate (14 m asl). The four localities are as follows, from north to south. 1) Galicia: westwards facing bank of mountain path, on granitic rocky ground; loose soil composed of turf mixed with granitic sand. Vegetation: dominated by low dense bushy cover of prickled broom Pterospartum tridentatum , mixed with dwarf gorse Ulex minor , white Spanish broom Cytisus multiflorus, Portuguese broom Cytisus striatus, Spanish heath Erica australis , tree heath E. arborea and dwarf Spanish heath E. umbellata , with scattered Scotch pine Pinus sylvestris ; partially grazed by cattle. Locality 2 km north of the border with Portugal. 2) Pitões das Júnias: footpath crossing dense Pyrenean oak Quercus pyrenaica woodland; soil loose, mixed of turf and coarse granitic sand, over granitic rock. Vegetation: shrub layer lateral to the path composed of dense dwarf gorse, wooly rock rose Halimium lasianthum , heather Erica sp. , common bracken Pteridium aquilinum , asphodel Asphodelus lusitanicus , Simethis mattiazzi and grasses. 3) Lamosa: sun exposed forest sandy road; granitic sandy soil over exposed granitic rock, with scattered boulders on higher areas. Vegetation: sparse mixed Pyrenean oak and maritime pine Pinus pinaster woodland, with shrub layer composed of white Spanish broom, heather Erica sp. , gorse Ulex sp. , dock Rumex sp. and dry grasses. 4) Ribeira do Torgal: low bank of dirt path along a thermophilic riverine valley, parallel to Ribeira do Torgal (Torgal creek); loose and deep somewhat sandy to silty soil overlaying pink shale rock. Vegetation: dense dry grasses with shrub layer composed of Mediterranean buckthorn Rhamnus alaternus , common hawthorn Crataegus monogyna, French lavender Lavandula stoechas , sage-leaved rock-rose Cistus salviifolius, common gum cistus C. ladanifer and strawberry tree Arbutus unedo ; hill sides with cork oak Quercus suber, Portuguese oak Q. faginea and wild olive tree Olea europaea var. sylvestris .

Comparison of the newly described female with other Iberian species in the genus Smicromyrme . The new form keys to ‘ Smicromyrme pusilla Klug’ using the key from Giner Marí (1944). The metasomal pattern parallels that of S. sulcisius Invrea, 1955 , and of S. suarezi Matias, 2024 , and like those species presents a spot of pale pubescence on vertex (see Matias 2024); however, S. matritensis can be easily distinguished by the very small scutellar scale, mandible structure, pygidial shape and mesosomal shape, among other features. It is most similar to S. pusillus , with which it shares numerous general structural features, including mandible and pygidium; it is a more robust and larger species, presenting a pale spot of pale pubescence on vertex, denser pale pubescence on metasoma (thus pattern better defined, though with weak medial notch apically on the T3 band, as S. suarezi ), and darkened pronotum (at least medially); see Discussion for further details.

Figures

FIGURE 11. Occurrence of Smicromyrme pusillus (Klug in Waltl) and S. matritensis (Mercet) in Portugal. A Smicromyrme pusillus, males (= S. suberrata Invrea; yellow dots: photographic records; see Remarks: Additional data) B Smicromyrme pusillus, females (= Physetopoda pusilla) C Smicromyrme matritensis (red dot: male). Localities are shown on UTM 10×10 km grid.

FIGURE 12. Smicromyrme matritensis (Mercet), male, Ribeira do Torgal (Odemira, Beja, Portugal), 15.vii.2019 (RMC817). A dorsal habitus B ventral habitus C head, frontal view D clypeus E mandible, dorsal view F mandible, lateral view G lateral habitus H wings, dorsal view I metasoma (T1–T3), dorsal view J metasoma (T2, S2; felt-lines), lateral view K genitalia, dorsal view L genitalia, ventral view M genitalia, lateral view. Scale bar: 1 mm (A–B, G), 0.25 mm (C, I–J), 0.1 mm (D), 0.2 mm (E–F, K–M), 0.5 mm (H).

FIGURE 13. Smicromyrme matritensis (Mercet), female, Ribeira do Torgal, 15.vii.2019 (RMC818). A dorsal habitus B ventral habitus C lateral habitus D pygidium E antenna F mandible, ventral view G head, frontal view H mesosoma, dorsolateral view I clypeus (white arrows indicate anterolateral tubercles) J metasoma, felt-line, lateral view K mesosoma, dorsal view L scutellar scale (white arrow). Scale bar: 1 mm (A–C), 0.1 mm (D, I, L), 0.5 mm (E, J), 0.2 mm (F), 0.25 mm (G–H).

FIGURE 14. Smicromyrme matritensis (Mercet), female, dorsal habitus, variation.A Pitões das Júnias, 24.v.2017 (RMC499) B Lamosa, 11.vi.2017 (RMC529) C Galicia, 14.v.2019 (RMC678). Scale bar: 1 mm (A–C).

FIGURE 15. Smicromyrme matritensis (Mercet), female, Galicia (Spain), 14.v.2019 (RMC678), variation. A head, frontal view B mesosoma. Scale bar: 0.5 mm.

FIGURE 16. Smicromyrme matritensis (Mercet), female, pygidium, variation. A Pitões das Júnias, 24.v.2017 (RMC499) B Lamosa, 11.vi.2017 (RMC529) C Galicia, 14.v.2019 (RMC678). Scale bar: 0.1 mm (A–C).

FIGURE 17. Known distribution of S. matritensis (Mercet). Legend. Black dots: type locality (Madrid; arrow) and MNCN_ Ent 63065. Yellow dots: new records (records of Pitões das Júnias and Galicia are both included in the same northernmost dot).

FIGURE 21. Mandible shape in female Iberian Smicromyrmini. A–D Smicromyrme (Astomyrme) pusillus (Klug in Waltl) [A Casal Sobrigal (Torres Vedras), 5.viii.2021 (RMC1421), lateral view: note second denticle not visible due to angle (compare with Figs 5G, 5I) B Cádiz (Spain), holotype: second denticle obscured; note abraded apical tooth C Mafra-Gare, (Mafra), 31.viii.2020 (RMC1212), dorsal view D Casal Palear—Carvoeira (Torres Vedras), 26.v.2021 (RMC1286), dorsal view] E Smicromyrme (Astomyrme) matritensis, Galicia (Spain), 14.v.2019 (RMC678), dorsal view F Ephutomma montarcense, Casal Sobrigal, 6.viii.2021 (RMC1430), dorsal view G Physetopoda cf. sericeiceps, 29.viii.2019, Fonte da Telha (RMC1039), dorsal view H Physetopoda cf. lucasii, Alfrívida (Castelo Branco), 31.vii.2019 (RMC917), dorsal view I Smicromyrme partitus, Casal Palear—Carvoeira, 25.iv.2022 (RMC1565), dorsal view J Smicromyrme ruficollis, Vila Nova de Milfontes (Beja), 17.vii.2019 (RMC848), dorsal view K Smicromyrme sulcisius, Fonte da Telha (Setúbal), 27.vi.2019 (RMC763), dorsal view. Legend. 1: first denticle; 2: second denticle. Scale bar: 0.1 mm (A–K).