Cresson mariastea Packer, 2021

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 mariastea Packer sp.nov.

Figs 21 , 22-24 , 25 , 27 , 29

Material examined.

9 ♀, 9 ♂ (several males missing apical metasomal segments): Holotype: ♀; Chile, Region I, 73 km E. Pozo Almonte; -20.312 -69.129; 3150m; 16.-21.iv.2012; pan trap; L. Packer ; MNHN . Paratypes: • 6 ♂, 7 ♀ paratypes identical data to previous; CAS, MNHN, PCYU, UCDC; • 1 ♂, 1 ♀ paratype; identical data to previous; 10.v.2012; net; PCYU; • 1 ♂ paratype; identical data to previous; 21.iv.-10.v.2012; PCYU.

Diagnosis.

This species, as well as the following new species, is most readily distinguished from C. parvispinosus by the reduced areas of red on the metasomal terga (Figs 22-24 ); T2 with at least a broad medial black band for the entire length of the tergum (Figs 23-24 ) and usually mostly black, sometimes entirely so other than for the subapical cream band, most of T1 is also black whereas C. parvispinosus has T1 and T2 entirely red (Figs 12-14 ), with at most the extreme base of the anterior declivitous surface of T1 black and T2 with at most a small apicomedial dark mark (in one male). Females can be differentiated from those of C. salitrera Packer sp.nov described below by the structure of T6. In C. mariastea the apicomedial spines are relatively long, subequal to, to longer than, the space that separates them (compare Figs 25 and 26 ), the lateral spines are usually less numerous, most commonly with 4 in C. mariastea (range 2 to 6) and 6 in C. salitrera (range 4 to 7) and they are also relatively shorter, less sharp and extend less than half the way up the side of the postgradular portion of the tergum as opposed to ~three-fifths the distance in C. salitrera . In males, the easiest distinguishing feature is the degree of curvature of the apical flagellomere. In C. mariastea the ventral surface towards the apex is at an angle of ~40° to the long axis of the flagellum, while this is ~80° in C. salitrera (compare Figs 27 and 28 ). There are also differences in surface sculpture between the two species, most clearly shown in the basal depressed area of T2 in both sexes which has large, distinct, deep and dense (i <d) punctures in C. mariastea (Fig. 29 ) but minute, sparse (i> 5d) punctures in C. salitrera (Fig. 30 ) which are largely imperceptible with the light microscope.

Description.

Holotype Female (Fig. 22 )

Dimensions: Body length 7.3 mm, forewing length 5.1 mm, head width 2.15 mm, ITW 1.3 mm.

Colouration: Black, following parts white to pale yellowish: mandible (except apical half increasingly dark towards apex, yellowish at midlength, red-brown at apex), labrum, lateral one-quarter of clypeus, narrow club-shaped mark on upper paraocular area adjacent to inner margin of compound eye extending from above upper tangent of antennal socket to below level of lower tangent of median ocellus, small mark on genal area above adjacent to posterior margin of compound eye, small mark towards side of pronotal collar separated by more than twice the width of the mark, pronotal lobe (margined with black above), small anterolateral mark on scutellum, triangular mark on mesopleuron anterior to mesocoxa, apical mark on all coxae (most extensive on mesocoxa where it occupies the outer third of the ventral surface), apicoventralless than two-thirds of profemur, anterodorsal surface of all tibiae (mostly pale yellow on pro- and mesotibiae, mostly white on metatibia), transverse subapical bands on T1-T5, entire only on T5, most broadly interrupted on T2, the interruptions are orange to orange-brown and narrower than the adjacent white bands. Scape yellow-orange apicoventrally. Following parts orange to orange-brown: torulus, all tarsi (probasitarsus suffused with yellowish, successive tarsomeres increasingly darker), posterior surface of metatibia entirely towards base, narrowing apically to absent at extreme apex; T1 and T3 narrow anterior margin to subapical pale transverse band, substantially broadened laterally on T1; T2 broadly towards side. Apical tergal and sternal depressions translucent straw laterally, orange-brown medially; T6 spines translucent orange-brown. S2 red brown, orange-brown towards margins; S3-S5 dark brown except red-brown towards apices.

Pubescence: Silver appressed and obscuring, or almost obscuring, underlying integument on lower paraocular area, genal area adjacent to compound eye, mesopleuron (sparser anteriorly and ventrally, absent posteriorly), scutellum posteriorly and dorsolateral portion of propodeum; somewhat less dense on clypeus, pronotal collar, anterior half of horizontal portion of T1; suberect longer setae ~0.7 MOD on most of genal area; sparse erect long whitish setae ≤ MOD on upper face, posterolaterally on pronotum, mesopleuron; similar setae somewhat shorter on mesoscutum and scutellum. Metasomal terga with short subappressed posteriorly oriented setae with sparse suberect setae intermixed, longest on T6, 0.3 MOD; short setae

Surface sculpture: Micropunctures very sparse on head and thorax except on vertexal and genal areas, abundant on metasomal terga and sterna; punctation mostly coarse and dense, almost crowded on face with interspaces raised among linear groups of punctures; genal area with dense small punctures i <d among irregularly spaced large ones, surface uneven somewhat rugose posteriorly. Mesoscutum densely punctate i <d except posteriorly on disc i ≤ 2d; punctures of scutellum as on upper face except sparser laterally; metapostnotum longitudinally rugoso-striate on horizontal portion, areolate posteriorly. Larger punctures of terga mostly dense i <d with some sparser areas laterally on T1 and towards apex of T2 and T3; basal depressed area of T2 deeply, coarsely and densely punctate i <d; sculpture of T6 similar to that of face; sterna punctures dense towards sides i <d, less regularly spaced medially, i = 1-4d on S2, mostly i <2d on S3-S5, i <d on S6 except midline largely impunctate.

Structure: Head almost 1.5 × as wide as long, 89:61; [labrum transverse, narrowly oval, three times as wide as medial length, W:L 36:12 apical margin transverse]; clypeus almost 3 × as wide as medial length, 61:21, lip almost half as wide as clypeus, 28; supraclypeal area minute, median length third as long as clypeus; AOD 1.7 × maximum width of F1 (17:10); supra-antennal area longer than maximum width 27:20, shorter than scape 32; frontal depression poorly defined dorsally; UOD:LOD:MINOD 66:47:35; IOD:OOD 27:25; scape twice as long as greatest width 32:16; pedicel shorter than wide 11:13; F1 more than twice as long as greatest width 22:10; F2 less than twice as long as greatest width 22:12, remaining flagellomeres decreasing in length from F3 to F9 (F9 L = W), F10 18:12; pronotal collar approximately 0.5 MOD medially, 10:19; [admedian line distinct anteriorly for less than half medial length of mesoscutum], scutellum with faint medial line with large shallow depression posteromedially; length of scutellum:metanotum:metapostnotum 39:15:30. T6 triangular, sides forming an angle of ~60°, with three acute teeth on each side, restricted to less than apical one-third of side of tergum, two apicomedial teeth longer than their basal width 7:5, separated by a distance subequal to their basal width. S2-S5 apical depressions ~0.3 MOD, narrowed medially, abruptly so on S4-S5.

Male. Dimensions: Body length 6.6 mm; forewing length 4.1 mm; head width 1.75 mm; intertegular width 1.1 mm.

Colouration: Black, following parts white to pale yellowish: mandible basal third (mid third orange, apical third red-brown), labrum, clypeus, supraclypeal area, paraocular area completely filling space between antennal socket and compound eye below, extending narrowly along eye margin above to just below lower tangent of median ocellus, small oval mark on genal area above behind compound eye, ventral surface of scape, ventral spot on pedicel, pair of small spots on pronotal collar separated by more than 2 MOD and <0.2 × the space that separates them, pronotal lobe (margined with black), large mark anterior to mesocoxa approximately equal in area to ventral surface of mesocoxa, ventral surface of all coxae except at base, ventral surface of profemur except basal fifth, apicodorsal mark on pro- and mesofemora, dorsal and most of posterior surfaces of pro- and mesotibiae, most of anterior surface of metatibia (posterior surface orange basally, orange-brown apically, blackish ventrally), anterior surface of all basitarsi and most of anterior surface of all second tarsomeres (remaining tarsomeres red brown), transverse subapical bands on T1-T6, very narrowly interrupted medially on T1, T4 and T5, more broadly interrupted on T2 and T3, complete on T6; S2 subapical band broad, S3 band narrow, S4 with small faint pale subapical mark. Pale marking on T1 narrowly margined with orange-brown, T2 with lateral orange brown spot anterior to pale band. Apical tergal; depressions translucent, largely colourless except orange-brown medially, apical sternal depressions pale straw except on S5 yellowish.

Pubescence: Silver appressed and obscuring, or almost obscuring, underlying integument on clypeus, lower paraocular area, frontal depressions, mesopleuron, metanotum posterolaterally, dorsolateral area of propodeum; somewhat sparser on genal area, pronotal collar, laterally on pronotum, anteromedially on mesoscutum, posterolaterally on scutellum, metanotum, most of horizontal surface of T1, anterior depressed area of T2. Longer, <1.5 MOD, erect whitish setae on frontal and vertexal areas, mesoscutum and scutellum; similar setae somewhat shorter and sparser on mesopleuron; metasomal terga with sparse suberect setae posteriorly on T4-T7, longest on T7 <0.5 MOD. Mesobasitarsal fringe setae <1.3 × as long as greatest width of mesobasitarsus. S2-S5 apicomedial setal fringe ~0.7 MOD in length medially.

Surface sculpture: As in female except as follows: Micropunctures absent on head and thorax, abundant on metasomal terga and sterna; genal area densely punctate, vertexal area and scutellum rugoso-punctate, mesoscutum more sparsely punctate posteriorly on disc, i ≤ 3d; lateral surface of propodeum somewhat rugulose below propodeal spine. Larger punctures of S2 denser i ≤ 2d; S6 sparsely punctate except anterolaterally i ≤ d.

Stucture: Head ~1.4 × as wide as long, 86:62: labrum transverse, narrowly oval, almost 3 × as wide as medial length, W:L 35:13, apical margin transverse; clypeus less than 3 × as wide as medial length, 61:22, supraclypeal area almost entirely obscured by frontal crest in frontal view, only extreme lower margin visible medially; AOD slightly greater than maximum width of F1, 12:10; supra-antennal area longer than maximum width 28:20, shorter than scape 31; frontal depression extending to <0.5 MOD below lower tangent of median ocellus; UOD:LOD:MINOD 55:38:26; IOD greater than OOD 23:16; scape more than 1.5 × as long as greatest width (31:18); pedicel length subequal to width; F1 twice as long as greatest width 20:10; F2 ~1.5 × as long as greatest width 19:12, remaining flagellomeres longer than wide, increasingly shorter from F3 to F10, F11 L:W 23:11, F11 somewhat falcate, ventral surface concave, apicoventral surface at ~40° to longitudinal axis of flagellum; pronotal collar approximately 0.5 MOD, 11:20; admedian line distinct anteriorly, obscure posteriorly, posteromedial scutellar pit obscure; length of scutellum:metanotum:metapostnotum 33:13:23. T7 somewhat semicircular with five narrow apical teeth, the median one shortest, the others subequal in length. Apical sternal depressions long, on S2 longer than the diameter of the largest punctures on the sternum; anterior and posterior medial angles of apical sternal depressions acute and obtuse, respectively on S2-S3, both approximately right angular on S4-S5.

Variation.

The extent of red colouration on the metasoma varies, four males have the red restricted to a narrow line immediately anterior to the apical whitish tergal bands on T1 and T2 (as in Fig. 24 ), four have the mark on T2 expanded into a lateral patch and one has even more extensive red marks quite similar to the male imaged for the following species (Fig. 33 ). Five females have an expanded lateral red mark on T2 and the anterior edge of the white mark on T1 margined with red while four have large lateral marks on T1 and T2 (as in Fig. 23 ). Some specimens have more broadly interrupted tergal bands on T2-T4. Two female paratypes have whitish subapical transverse bands on S2 and one has such marks also on S3. Females vary in the size of the lateral pale mark on the scutellum from absent to extending for approximately half the length of the lateral margin. One male paratype has the pale spots on the pronotal collar extensive, almost as wide as the space that separates them, while three of them have these marks entirely absent. One male has a small pale lateral mark on the scutellum. One male lacks the pale mark on the pedicel while two also have pale marks ventrally on F1 and F2. The larger males have the lateral surface of the propodeum with dorsolaterally oriented carinae above as in the female. One male has the petiole of the second submarginal cell duplicated on one side, forming an additional, small, quadrate cell anterior to the normal second submarginal cell. One female has the petiole on the right forewing second submarginal cell almost absent.

Males vary in size from a head with of 1.6 to 2.02 mm; females vary in head width from 1.65 to 2.15 mm.

Etymology.

This species is named in honour of the late Maria Stea. During her too-short time at York University she was tireless in her efforts to assist the hymenopterists in the Biology Department.

Comments.

All specimens of Cresson mariastea are from the mountainous area Northeast of the oasis town of Pica, and almost due South of Mamiña (less than 30 km from either) in an area known as the Pica Highlands (Fig. 21 ). This area has yielded many interesting species of Apoidea in recent years, including a new genus of fideliine ( Praz and Packer 2017) and a new species of Colletes ( Ferrari 2017) as well as its presumptive cleptoparasite, a recently described species of Isepeolus ( Packer and Graham 2020).

An undescribed species of Parapiagetia and a species of Tachysphex I have not been able to identify were found simultaneously with C. mariastea and are its potential hosts.

Figures

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 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 25 - 30. Characters used to differentiate C. mariastea and C. salitrera 25 T 6 of female C. mariastea, 26 T 6 of female C. salitrera. Scale bars: 0.5 mm. 27 F 11 of male C. mariastea 28 F 11 of male C. salitrera. Scale bars: 0.25 mm. 29 base of T 2 C. mariastea 30 base of T 2 of C. salitrera. Scale bars: 100 µm.

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.

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