Cresson parvispinosus (Reed)

Packer, Laurence, 2021, A Revision of Cresson Pate (Hymenoptera, Apoidea, Bembicidae) with the description of two new species, Journal of Hymenoptera Research 85, pp. 81-117 : 81

Cresson parvispinosus (Reed)

Figures 1-3 , 4 , 5 , 6 , 8 , 9 , 10-11 , 12-14 , 15-16 , 17-19 , 20 , 21 , 34

Nysson parvispinosus Reed, 1894:641, ♀ Lectotype (here designated): ♀, Chile, Colchagua Province; no specific locality (MCZ); Dalla Torre 1897: 573, catalog; Pate 1938: 155, description of genus; Maidl and Klima 1939: 149, catalog; Fritz 1955: 14, redefinition of genus; Bohart and Menke 1976: 476, generic key, diagnosis, range, systematic position, checklist; Sielfeld 1980: 74, catalog; Amarante 2002: 20, catalog; Chiappa 2012: 9, catalog.

Material examined.

55 ♀, 47 ♂: Lectotype ♀; Chile, Colchagua Province [Region VI]; 1890; E.C. Reed; MCZ-ENT-17200 ; Additional material: 1 ♂; • Chile [Region IX], 20 km E. of Temuco ; [-38.7 -72.35]; 7.i.1951; Ross and Michelbacher; CAS ; • 1 ♀: [Region VII] Curicó Prov., Fundo La Montaña, Estero La Palma at Rio Teno , 6 km E. of Los Quenes ; [-35.00 -70.75]; 4.i.1967; M.E. Irwin; CAS ; • 1 ♀; Valparaiso Province [Region V], Valparaiso; [-33 -71.5]; 26.xi.1919; P. Herbst; MCZ; MCZ-ENT 00731885 ; • 1 ♀; identical data as previous; CAS ; • 1 ♀; identical data as previous; 12.i.1921; MCZ (MCZ-ENT 00731886) ; • 2 ♀, 3 ♂; identical data to MCZ-ENT 00721886; CAS; • 1 ♀; Valparaiso [Region V], Concon ; [-32.9 -71.5]; 74. xii.1910; P. Herbst; MCZ; MCZ-ENT 00731884 ; • 1 ♂; identical data to MCZ-ENT 00731884; CAS; • 1 ♂; [Region V], Rio Blanco ; 7.xii.1917; P. Herbst; CAS ; • 1 ♀; Valparaiso Province, [Region V] Olmué; [-33.0 -71.2]; 4.ii.1920; P. Herbst; MCZ; MCZ-ENT 00731883 ; • 1 ♂ (dissection code 65-xi-250); [Region V] Perales, Quilpué; [-33.05 -71.4]; 4.ii.1925; P. Herbst; CAS ; • 1 ♀; Valparaiso Province [Region V]; Marga-Marga ; 9.i.1919; P. Herbst; MCZ; MCZ-ENT 00731880 ; • 1 ♂; Santiago Province [Region Metropolitana], Cerros de Tiltil ; [-33.1 -70.9]; 18.i.1919; P. Herbst; MCZ; MCZ-ENT 00731881 ; • 1 ♂ identical data as previous; 2000m; i.1920; MCZ; MCZ-ENT 00731882 ; • 1 ♂ ( “homotype” A.R. Menke); [Region V], Valparaiso; 19.i.1921; P. Herbst; UCDC ; • 1 ♀; [Region V], Altos de Lliu Lliu ; [-33.1 -70.9]; 20.i.1919; P. Herbst; UCDC ; • 1 ♂; [Region Metropolitana], Santiago; 1922; F. Jaffuel; UCDC ; • 1 ♀; [Region Metropolitana], Santiago, Maipu, Quebrada de La Plata ; 26.xii.1966; L. Stange; UCDC ; • 1 ♀; [Region IV], 10 km E. of Fray Jorge Nat [iona]l P[ar]k; [-30.6 -71.6]; 28.xii.1966; dry wash; M.E. Irwin; CAS ; • 2 ♂, 1 ♀; Region IV, El Pangue ; -30.164 -70.664; 1700m; A Ugarte; PCYU ; • 33 ♂, 40 ♀; Region III, 13.5 km W. of Los Sapos ; -28.019 -70.554; 500m; 22-25.x.2010; pan traps; L. Packer; CAS, MNHN, PCYU, UCDC and ZMBH ; • 1♂; Region III, Rd. to Pastos Largos ; -28.164 -69.791; 2100m; 6.xi.-11.xii.2013; S. Monckton and J. Postlethwaite; pan trap; PCYU ; • 1 ♀; Chile; UCDC.

Diagnosis.

The type species of the genus can be differentiated from the new species most easily by the more extensive red colouration of the metasoma in both sexes with T1-T2 entirely red (except for the extreme anterior margin and one male has a small posteromedial dark mark on T2) (Figs 12-14 ). Females usually also have T3 entirely red. The other species have T1 and T2 black at least medially, although T1 is usually almost entirely black (see Figs 24 , 31 ). The pronotal collar is relatively longer, at least two-thirds as long as MOD, whereas in the two other species it is approximately ½ as long as MOD (compare Figs 34 and 35 ).

Redescription.

Lectotype Female (Fig. 10 )

Dimensions: Body length 6.1 mm, head width 2.05 mm, forewing length 4.4 mm, ITW 1.15 mm.

Colouration: Black except as follows: cream to pale yellow on labrum, basal half of mandible (rest orange to red-brown), clypeus lateral one-third (entire apical bevelled region and lip orange-brown), small semicircular-triangular mark on upper paraocular area adjacent to compound eye, small spot on genal area above adjacent to compound eye; large lateral marks on pronotal collar almost twice as wide as the space that separates them, pronotal lobe, lateral spot on scutellum, narrow oblique mark in front of mesocoxa, small apicolateral mark on meso- and metacoxae, apicoventral two-thirds of profemur, narrow stripe on anterior surface of pro- and mesotibiae (suffused with orange on protibia), narrow dorsal stripe on metatibia (rest of legs dark brown, except metatibia posterior surface and all tarsi orange to orange-brown), medially interrupted narrow subapical bands on T1-T5. Most of ventral surface of scape yellow brown. Following parts orange-red: T1 and T2, T3 laterally; S1 and S2 (both suffused with red-brown medially), S3 narrowly subapically, S4 narrowly apicolaterally. Apical tergal and sternal depressions pale translucent brown to straw; T6 teeth pale brown.

Pubescence: [described from female from Valparaiso, MCZ-ENT 00731886]: Silver, appressed, obscuring integument only on lower paraocular area, genal area close to compound eye, most of mesopleuron and dorsolateral area of propodeum; sparser on clypeus, sparser and suberect on genal area posteriorly. Face with erect to suberect pale setae <1.2 MOD, those of lower frontal area curved ventrally; pronotal collar and mesoscutum anteriorly with sparse, posteriorly oriented appressed setae; mesoscutum, scutellum, metanotum and mesopleuron with sparse erect setae <MOD. Metasomal terga and sterna with sparse short subappressed posteriorly oriented setae ≤ 0.4 MOD; suberect setae intermixed on terga <0.5 MOD, these longer and denser on more posterior sterna, <MOD on S6.]

Surface sculpture [described from female from Valparaiso MCZ-ENT 00731886: Head, mesoscutum and mesoscutellum with minute punctures scattered in interspaces among large dense (mostly i ≤ d) areolate-punctate background; frontal area punctures denser, in rows with interspaces almost absent; upper paraocular area punctures smaller, irregularly spaced i <d; vertexal area punctate-reticulate; genal area with small punctures dense i <d sparser below, larger punctures scattered. Mesoscutum densely punctate i ≤ d except for a few larger interspaces posteriorly on disc, scutellum densely punctate i <d except punctures sparse on pale lateral portion. Mesopleural punctures coarse i <d except posterior glabrous portion with few scattered punctures restricted to ventral half and a subvertical row anterior to meso-metapleural suture; metapleuron with few short horizontal carinae posterodorsally; side of propodeum posterodorsally with irregularly sized shallow punctures among costae; metapostnotum horizontal portion longitudinally carinate-rugose with numerous faint transverse striae between carinae, areolate posterodorsally. Metasomal terga doubly punctate, minute punctures abundant; large coarse punctures dense i ≤ 2d on T1, i ≤ 4d on T2; T3-T6 punctures increasingly dense, i <1.5d on T5, T6 areolate-punctate; S2 minute punctures sparse and obscure, larger punctures i = 0.5-2d; S3-S5 minute punctures distinct, larger punctures mostly i ≤ 1.5d; S6 i <d somewhat sparser along midline.]

Structure. Head ~1.3 × as wide as long, 83:60; [labrum transverse, narrowly oval, ~3 × as wide as medial length, W:L 41:14, aboral surface somewhat and apical margin conspicuously concave;] clypeus more than 2.5 × as wide as medial length, 63:24, lip ~half as wide as maximum width of clypeus 32:64; supraclypeal area median length one-quarter that of clypeus, 6; AOD 1.5 × maximum width of F1 (18:12); supra-antennal area with a complete somewhat dorsolaterally oriented lamella at lower third and several similarly oriented carinae above it and a few smaller ones below, area longer than maximum width 35:26, shorter than scape 37; frontal depression continuing above to somewhat below lower tangent of median ocellus; inner margin of compound eyes markedly convergent below UOD:LOD:MINOD 64:45:33; IOD = OOD; scape less than twice as long as greatest width (37:20); pedicel length = width; F1 ~2 × as long as greatest width 25:12; F2 ~1.5 × as long as greatest width 24:14, [remaining flagellomeres longer than wide, decreasing in length from F3 to F9, F10 longer L:W 22:16]; pronotal collar shorter medially than MOD, 15:19; [admedian line more than half medial length of mesoscutum], scutellum not depressed medially but with large posteromedial pit; length of scutellum:metanotum:metapostnotum 40:18:23. T6 somewhat triangular, sides slightly less than right angular to each other, with five teeth on each side, two apicomedial teeth the longest with length and basal width subequal, separated by somewhat more than their length. S2-S4 apical sternal depressions <0.25 MOD, narrower medially, absent medially on S5.

Male: based upon the specimen from Cerros de Tiltil (MCZ-ENT 00731881), this specimen bears a minute red label devoid of script. (Fig. 11 ).

Dimensions Body length 4.93 mm, head width 1.47 mm, forewing length 3.45 mm, ITW 0.8 mm.

Colouration: Black except as follows: cream to pale yellow on basal two-thirds of mandible (rest orange to red-brown), clypeus (except lip orange-brown), supraclypeal area, lower paraocular area mark narrowly extending along inner eye margin to 1 MOD below lower tangent of median ocellus, small spot on genal area above adjacent to compound eye, ventral half of scape, small spot on pedicel, large lateral marks on pronotal collar twice as wide as space that separates them, pronotal lobe (margined with orange-brown dorsally), large lateral spot on scutellum, most of propodeal spine, mark in front of mesocoxa as large as ventral surface of mesocoxa, most of ventral surfaces of all coxae, most of ventral surface of profemur, dorsal surface of pro- and mesotibiae extending onto posterior surfaces apically, narrow ventral stripe on apical half of mesofemur, most of anterior surface of metatibia, anterior surfaces of all basitarsi (rest of metatibia and maining tarsomeres orange to pale orange-brown), medially interrupted narrow subapical bands on T1-T6, most widely separated on T2 and most narrowly on T6. Following parts orange-red: T1 and T2, T3 apicolaterally; S2 (suffused with red-brown medially), S3-S5 subapical markings increasingly narrow on more apical sterna. Apical tergal and sternal depressions pale translucent orange-brown.

Pubescence: As in female except for S2-S5 with dense apicomedial setal fringes, setae long, medially 0.75 MOD.

Surface sculpture: As in female except as follows: micropunctures almost absent on face and mesoscutum; upper paraocular area more sparsely punctate i> d; vertexal area punctures variable in size; lateral surface of propodeum punctures among carinae deeper.

Structure: Head ~1.3 × as wide as long, 81:60; labrum transverse, narrowly oval, less than 2.5 × as wide as medial length, W:L 37:16, apical margin somewhat concave medially; clypeus ~2.5 × as wide as medial length, 69:27, lip almost half as wide as whole clypeus, 33:69; supraclypeal area minute, median length one-quarter as long as clypeus 7:27; AOD equal to maximum width of F1; supra-antennal area much longer than maximum width 31:18, shorter than scape 34; frontal depression poorly demarcated above; UOD:LOD:MINOD 60:40: 29; IOD greater than OOD 28:23; scape almost twice as long as greatest width 34:18; pedicel length subequal to width; F1 more than twice as long as greatest width 23:10; F2 less than twice as long as greatest width 20:12, remaining flagellomeres longer than wide, increasingly shorter from F3 to F10, F11 L:W 18:11, F11 somewhat falcate, ventral surface markedly concave. Pronotal collar shorter medially than MOD, 13:19; [admedian line more than half medial length of mesoscutum], scutellum narrowly impressed medially, with large posteromedial pit; length of scutellum:metanotum:metapostnotum 35:14:18. T7 somewhat semicircular with five apical teeth, median one shortest, submedian ones longest. Apical sternal depressions short; anterior angle of all medial interruptions of apical sternal depressions acute, posterior angles obtuse, less markedly so on more posterior sterna.

Variation.

In both sexes there is variation in the colour of the propodeal spine, ranging from mostly semi-translucent white through cream to partially or entirely black. The extent of the pale subapical cream bands on the metasomal terga also varies: on T1 and T4 in females, T1 and T5 in males, the band may be interrupted medially or entire, it is always interrupted on T2-T3 in females and T2-T4 in males but may also be entire on T5 in females and T6 in males. The number of metasomal terga and sterna that are orange-red varies (Figs 12 - 16 ). For terga, both sexes always have T1 and T2 orange, both sexes sometimes have T3 entirely orange, but only in females does this sometimes extend to the entirety of T4. For the sterna, S2 is sometimes not entirely orange in both sexes, females sometimes have S2-S4 entirely orange, though in males only S2-S3 may be entirely orange (Fig. 16 ). Figures 15 and 16 show the relative frequency of the number of terga or sterna that are red separately for males and females. Clearly females, on average, have more extensive orange markings.

The frontal depressions are often almost obscured by silvery setae and vary somewhat in extent sometimes reduced such that their dorsal margin is 1 MOD below the lower tangent of the medial ocellus. The mesoscutal punctation varies from being fairly uniformly dense i <0.5d, to having quite a few interspaces at least as wide as the adjacent punctures especially on the posterior third.

In males: 1) The supraclypeal area varies from entirely whitish to entirely black with intermediate conditions of brown or dappled pale and dark (Figs 17-19 ). 2) There is variation in the extent of pale colouration on the antenna, pronotum and scutellum. Some individuals have pale spots on the ventral surface of the pedicel and F1 and F2, while others have these lacking or restricted to the pedicel. The colour of these markings also varies from pale cream to orange-brown. The markings on the pronotum and scutellum, while always present, vary somewhat in size.

In females the extent of the pale marking along the inner margin of the compound eye is variable: it is subequal in length to MOD in the lectotype but may extend more narrowly to below the upper tangent of the supra-antennal area. There is minor variation in the extent of yellow-brown on the scape and of pale colouration on the clypeus, pronotum and scutellum.

Two males (MCZ-ENT 00731882) have an additional cross-vein towards the apex of the second discoidal cell. This can be seen in figure 11 as forming a wishbone shaped outline that is almost a mirror image of the second submarginal cell on either side of the median vein. In the second specimen the additional cell is much smaller. There is variation in the size of the second submarginal cell such that the petiole can be almost absent to extending for more than two-thirds the distance between the marginal and second discoidal cells. One female has the right forewing with an additional vein that separates off a small quadrate cell towards the distal extremity of the second submarginal cell. Another has this additional vein incomplete, and on the left wing. One male from El Pangue has the second submarginal cell sufficiently reduced it is almost circular with a diameter of less than three vein widths.

The two sexes average sizes are very similar; for the head width for the large sample from Region III females average 2.32 mm, SD. 0.215, n = 33, maximum 2.77 mm, minimum 1.82 mm; males average 2.33 mm, SD 0.16, n = 28, maximum 2.65 mm, minimum 2.03 mm. The series from the MCZ contains some smaller specimens: the smallest male has a head width of 1.45 mm, and the smallest female 1.48 mm. The smallest of all males available, the individual from El Pangue noted above, has a head width of 1.3mm.

Comments.

There has been confusion over the nature of the type material of this species. Reed (1894) described a female specimen: his description starts with the female symbol. This is confirmed by the statement that the clypeus is pale marked on either side "una punta en cada lado del marjin anterior del clípeo …. amarillo blanquizco"; the male, in contrast, has an entirely pale clypeus. However, at the end of the description he implies that he has seen only two males, both from Colchagua "[H]e encontrado dos ejemplares, machos, de esta especie en Colchagua". This is the only statement made about the provenance of any material of this species he studied. In the material from MCZ there is a single specimen from Colchagua and it is the only specimen bearing a red “type” label (Fig. 20 ). Seemingly confirming Reed’s confusion over the gender of the material he described, it bears a label stating that it is a male (Fig. 20 ). Consequently, I designate this specimen, which is a female, as the lectotype. As no other specimen from Colchagua is among the MCZ material, no paralectotype is designated at this time. Indeed, as none of the remaining MCZ material was available to Reed at the time of his publication (1894), they cannot be considered as syntypes. Pate (1938) was correct in noting that the “type” was a female, but implied that Reed had also described a male even though none of the males he listed had been collected prior to 1919, 25 years after Reed’s publication.

The lectotype female (Fig. 10 ) is in reasonably good condition, albeit with some apparent damage from mould with dried mycelia obscuring some features and it is missing the following parts: left antenna, right antenna beyond F4, left tegula, left mesotarsus beyond the 3rd tarsomere, entire left metatarsus, right metatarsus beyond 2nd tarsomere. Its condition necessitated some parts of the redescription to be made from a different specimen; the MCZ specimen from Valparaíso: MCZ-ENT 00731885 being chosen for this purpose.

Additional records for specimens not examined in this study but cited by Pate (1938) are as follows: Chile • 1 ♂; Valparaiso Province [Region V], Valparaiso; 25.xii.1919; P. Herbst; • 1 ♂, 1 ♀; Limache; [-33.0 -71.3]; 31.i.[no year]; A. Faz; AMNH; • 2 ♂ same collector as previous; CUIC.

Pate (1938) listed a female specimen from the MCZ with the locality "VALPARAISO PROVINCE, Concepcion, 4. Dec. 1910", I believe that Pate misread the label, as it actually states “Concon”, with the gender of the specimen and date of its collection being the same, this specimen is listed in the material examined section above. Concon is just north of Valparaiso, there is no location known as “Concepcion” in Chile’s Region V (Ugarte, pers. comm.). The well known Chilean Concepción [ Concepción de la Madre Santissima de la Luz] is the capital of Region VIII.

The type species of the genus is known from low altitudes in Central Chile, from 28°S in Region III in the north to ~38.7°S in Region IX in the south, Santiago to the east and Valparaiso and near Temuco to the west (Fig. 21 ). Despite our having collected extensively around Santiago and in the area between Santiago and Valparaiso, we have found no specimens of C. parvispinosus here. This area has been severely impacted by agricultural intensification since the time of the earlier collections of this species, but there remain large areas of good quality habitat especially in the more rugged areas, such as around Til-til (where we have collected frequently). Instead, most of our material comes from the southern Atacama Desert, over 500 km further north than the previous most northerly record for the species. Despite the distance and more arid habitat, it seems clear that the populations are conspecific, in that extensive study failed to reveal any consistent morphological differences among specimens from Region III and those from Regions V, VI, VII, IX and Metropolitana.

The Los Sapos locality where large numbers of C. parvispinosus were collected was a small, vegetated patch situated within a large area that was very dry and otherwise devoid of greenery over the time the samples were collected. It seems that roadwork immediately adjacent to the site had resulted in concentration of runoff in a small area (see fig. 30 in Mir Sharifi et al. 2018). Considerable numbers of bees and wasps were collected in traps (mostly bright blue) left out here for a few days and these included putative hosts for this cleptoparasitic nyssonine. The most likely hosts are among the following species for which large numbers of individuals were collected in the same traps as C. parvispinosus : two species of Tachysphex , identified using Pulawski (1974) as T. rufitarsis (Spinola) and a species perhaps allied to T. reedi Menke and two undescribed species of Parapiagetia Kohl.

Figures

Figure 4. Apex of T 1 and base of T 2 of female C. parvispinosus to show measurement of puncture spacing (diameter (d) - blue line, interspace length (i) red line (here i ~ 2 d as indicated to the bottom right) and the double-edged nature of the apex of the tergum, indicated by the yellow curly bracket. Scale bar: 100 µm.

Figure 5. Oblique ventral view of metasoma of male C. parvispinosus to show apicomedial setal fringes situated within the medial gap in apical sternal depressions along with the angles formed at the margin of the gap (inset). The angle formed by the red and blue lines indicates the anterior angle, that formed by the blue and yellow lines the posterior angle. Scale bar: 0.5 mm.

Figure 6. Part of face and parts of antenna of male C. parvispinosus to show landmarks used in some measurements. Red line: AOD; blue line: scape length; yellow line: scape width; green line: pedicel length (note only the swollen part contributes to this measurement); purple line: pedicel width; pink line: F 1 length; white line: F 1 width; inset red dashed line: F 11 length; blue dashed line: F 11 width. Scale bars: 0.25 mm.

Figure 8. Face of C. parvispinosus to show landmarks used in some measurements. Red line: head length; pink line: head width; yellow line: UOD; purple line: MINOD; blue line: LOD; green curly bracket shows extent of frontal depression. Scale bar: 0.5 mm.

Figure 9. Dorsal view of mesosoma of C. parvispinosus to show landmarks for some measurements. Black line: length of pronotal collar; blue line: length of mesoscutum; red line: ITW; green line: length of scutellum; purple line length of metanotum; yellow line: length of dorsal surface of metapostnotum (note that the latter is taken from the metanotal-metapostnotal suture to the transverse carina closest to the change in angulation from approximately horizontal to approximately vertical surfaces of the metapostnotum). Scale bar: 0.5 mm.

Figure 20. Labels from the lectotype of C. parvispinosus.

Figure 21. Distribution map of all records of Cresson spp. Red symbols: C. parvispinosus, star: the type locality for C. parvispinosus; blue: C. mariastea; green: C. salitrera. Scale bar: 500 km.

Figures 1 - 3. Supra-antennal areas of C. parvispinosus 1 standard light photomicrograph of male, red line indicates measurement of length of the area, the blue line indicates its width. Scale bar: 0.5 mm. 2 ESEM of female, the white arrow indicates the lamella. Scale bar: 300 µm. 3 ESEM of another female showing different number of carinae to that in figure 2. Scale bar: 200 µm.

Figures 10 - 11. Cresson parvispinosus specimens used in the redescription of the species 10 lectotype female 11 male from Cerros de Tiltil (MCZ-ENT 00731881). Scale bars: 1.0 mm.

Figures 12 - 14. Metasomas of C. parvispinosus to show variation in colour 12 male with T 1 - T 2 red 13 female with T 1 - T 3 and sides of T 4 red 14 female with T 1 - T 2 and sides of T 3 red. Scale bars: 1.0 mm.

Figure 15 - 16. Frequency histograms of different colour patterns of C. parvispinosus 15 for metasomal terga 16 for metasomal sterna. Females in grey, males in black.

Figures 17 - 19. Heads of male C. parvispinosus to show variation in colour of supraclypeal area 17 area entirely white 18 area entirely black 19 area dappled with asymmetrical white mark (white arrow). Scale bars: 1.0 mm.

Figures 34 - 35. Relative dimensions of MOD and pronotal collar medial length for couplet 1 of identification key of Cresson species 34 C. parvispinosus and 35 C. salitrera. Red lines MOD, blue lines medial length of pronotal collar. Scale bars: 1.0 mm.

Figures 22 - 24. Cresson mariastea 22 a paratype female, lateral view 23 holotype female, dorsal metasoma 24 male, dorsal metasoma. Scale bars: 1.0 mm.

Figures 31 - 33. Cresson salitrera 31 male, lateral view 32 holotype female, dorsal metasoma 33 male, dorsal metasoma. Scale bars: 1.0 mm.