Andrena (Avandrena) juliae Wood, sp. nov.

Wood, Thomas J., 2023, The genus Andrena Fabricius, 1775 in the Iberian Peninsula (Hymenoptera, Andrenidae), Journal of Hymenoptera Research 96, pp. 241-484 : 241

Andrena (Avandrena) juliae Wood, sp. nov.

Type material.

Holotype. Spain: Cádiz, Parque Natural Los Alcornocales, Las Algamitas, Finca Murtas, 36.3273°N, - 5.5986°W, 18.iii.2023, 1♀, leg. T.J. Wood, OÖLM.

Paratypes. Spain: Cádiz, Parque Natural Los Alcornocales, Las Algamitas, Finca Murtas, 18.iii.2023, 1♀, leg. T.J. Wood, TJWC; Cádiz, Tarifa, 1 km N, grazing fields, 23.iii.2023, 1♀, leg. T.J. Wood, OÖLM.

Description.

Female. Body length: 9 mm (Fig. 47A ). Head: Dark, 1.4 times wider than long (Fig. 47B ). Clypeus weakly domed, with fine granular shagreen, dull, overlain by weak raised rugosity, rugosity forming weak, obscure, and interrupted raised latitudinal striations; remaining surface impunctate. Process of labrum rounded rectangular, twice as broad as long, surface smooth and shiny. Gena equalling width of compound eye; ocelloccipital distance equals diameter of lateral ocellus. Foveae moderately broad, occupying half space between compound eye and lateral ocellus, short, ventrally extending to level of antennal insertions; foveae filled with black hairs (Fig. 47C ). Face medially with light brown-white hairs covering clypeus and antennal insertions, intermixing with black hairs, becoming entirely black haired along inner margin of compound eyes and frons; gena and vertex with long light brown hairs, longest hairs equalling length of scape. Antennae dark, A7-12 ventrally slightly lightened grey by presence of scales; A3 equalling A4+5+6. Mesosoma: Scutum and scutellum with fine granular shagreen, very weakly shiny, predominantly dull, underlying surface shallowly and obscurely punctate, punctures separated by 1-2 puncture diameters (Fig. 47D ). Pronotum rounded. Mesepisternum and dorsolateral parts of propodeum with fine granular shagreen, predominantly dull, shagreenation overlain by fine network of raised rugosity, not forming a linked network. Propodeal triangle short and broad, slightly depressed below level of dorsolateral parts of propodeum, with extremely fine granular shagreen, basal 2/3rds covered with raised longitudinal rugae, propodeal triangle thus strongly contrasting dorsolateral parts of propodeum (Fig. 47E ). Mesepisternum with long strongly plumose hairs, hairs predominantly pale with some intermixed black hairs, hairs clearly exceeding length of scape. Scutum and scutellum with strongly plumose light brown hairs, intermixed with black hairs medially. Propodeum with long strongly plumose light brown hairs, propodeal corbicula incomplete, dorsal fringe weak and poorly defined, internal surface with numerous pale simple hairs. Legs dark, tarsi obscurely lightened reddish brown; pubescence light brown. Flocculus complete, strong, composed of strongly plumose light brown hairs; femoral and tibial scopa composed of light brown simple hairs. Hind tibial claws with strong inner tooth. Wings hyaline, stigma and venation dark orange, nervulus interstitial. Metasoma: Terga dark, apical rim of marginal areas narrowly lightened hyaline-yellow (Fig. 47F ). Tergal discs with scattered and small hair-bearing punctures, punctures separated by 3-4 puncture diameters, underlying surface finely shagreened, silky smooth, shiny. Tergal discs with sparse upstanding pale hair, T2-4 with dense apical whitish hair bands that obscure underlying surface. Apical fringe of T5 and hairs flanking pygidial plate dark brown; pygidial plate apically rounded, surface flat and featureless.

Male. Unknown.

Diagnosis.

Andrena juliae can be recognised as belonging to the subgenus Andrena Avandrena due to its moderate to small body size (9 mm), short and wide head (clearly wider than long), and short and wide foveae that are only slightly longer than wide, as well as the behavioural observation that it is strongly associated with Erodium ( Geranicaceae , see Remarks). The posterior face of the hind femora lacks spines, separating the species from A. avara Warncke, 1967 and A. panurgina De Steffani, 1889 and placing it close to A. melacana Warncke, 1967 and A. erodiorum Wood & Ortiz-Sánchez, 2022.

Andrena juliae can be separated from both species by the structure of the propodeum which has the dorsolateral parts with fine granular shagreenation that is overlain by a fine network of raised rugosity, this rugosity not forming a linked network. The propodeal triangle itself is clearly differentiated, slightly depressed below the level of the surrounding parts of the propodeum and delineated by fine carinae, the surface with fine granular shagreenation and with a network of raised longitudinal carinae covering the basal 2/3rds. In contrast, A. erodiorum has the dorsolateral parts of the propodeum shiny, overlain with a fine network of raised rugosity that joins together to form a clear network (Fig. 73E ). The propodeal triangle is clearly delinated by raised carinae and with the entire surface covered with longitudinal carinae. In A. melacana , the dorsolateral parts of the propodeum are entirely covered with fine granular shagreen, without an overlay of raised rugosity, with the propodeal triangle not depressed and with even finer granular shagreen, not strongly differentiated from the surrounding areas.

The propodeum of A. juliae therefore sits between both comparison species and is distinct from both. It can be further separated by the pubescence of the mesepisternum which is predominantly composed of pale hairs, with approximately 30% of these hairs black (in A. melacana with 50-60% of the hairs of the mesepisternum black; in A. erodiorum with only 10% of these hairs black), by the facial foveae which occupy half of the space between the compound eye and a lateral ocellus (occupying ¾ of this space in A. erodiorum ), by the colour of the hairs of the apical fringe of T5 and those flanking the pygidial plate which are dark brown (golden-brown in A. erodiorum , dark brown in A. melacana ), and by the pubescence of the terga which are covered in sparse erect white hairs, T2-4 with dense apical hair bands of white hairs that obscure the underlying surface (in A. melacana terga with sparse short pubescence, only forming weak apical tergal hair bands that do not obscure the underlying surface; pubescence very similar in A. erodiorum ).

Remarks.

All specimens were collected from Erodium spp. The two females from Las Algamitas were collecting pollen from this genus ( Erodium pollen can be seen in Fig. 47A ). Across sampling locations in Cádiz province during March 2023, four species of Avandrena were active, specifically A. avara sensu stricto, A. juliae , A. melacana , and A. panurgina . All species appear to be narrowly oligolectic on Erodium (see below), and A. juliae could be found in direct sympatry with A. avara sensu stricto, A. melacana , and A. panurgina at the Las Algamitas site and with A. melacana and A. panurgina at the Tarifa site. Andrena erodiorum is currently known only from south-eastern Spain (Albacete). One A. juliae female showed abraded body hairs, and no males were captured, implying that the flight season may begin in early March or even late February, perhaps offering a reason as to why this species has been overlooked until now.

Etymology.

Dedicated to my friend and colleague Julia Jones (University College Dublin, Ireland) who invited me on the University field course during which this new species was discovered.

Distribution.

Spain ( Cádiz province).

Other material examined.

Andrena avara s. str.: Spain: Cádiz, Parque Natural Los Alcornocales , Las Algamitas, Finca Murtas, 18.iii.2023, 1♀, leg. T.J. Wood, TJWC; Cádiz, Bolonia, El Lentiscal, 24.iii.2023, 1♀, leg. T.J. Wood, TJWC .

Andrena melacana : Spain: Cádiz, Parque Natural Los Alcornocales , Las Algamitas, Finca Murtas, 18.iii.2023, 3♂, 2♀, leg. T.J. Wood, TJWC; Cádiz, Tarifa, 1 km N, grazing fields, 19.iii.2023, 4♂, 6♀, leg. T.J. Wood, TJWC .

Andrena panurgina : Spain: Cádiz, Parque Natural Los Alcornocales , Las Algamitas, Finca Murtas, 18.iii.2023, 4♂, 3♀, leg. T.J. Wood, TJWC; Cádiz, Tarifa, 1 km N, grazing fields, 19-23.iii.2023, 6♂, 2♀, leg. T.J. Wood, TJWC .

Figures

Figure 47. Andrena (Avandrena) juliae sp. nov. female A profile B face, frontal view C head, dorsal view D scutum, dorsal view E propodeum, dorsal view F terga, dorsal view.

Figure 73. Andrena (Andrena) fulva (Mueller, 1776), female A terga, dorsal view; Andrena (Andrena) helvola (Linnaeus, 1758), female B terga, dorsal view; Andrena (? Euandrena) Andrena ramosa Wood, 2022, female C propodeal corbicula, profile view; Andrena (Didonia) mucida Kriechbaumer, 1873, female D process of the labrum, ventral view; Andrena (Avandrena) erodiorum Wood & Ortiz-Sanchez, 2022, female E propodeum, dorsal view; Andrena (Avandrena) melacana Warncke, 1967, female F propodeum, dorsal view; Andrena (Nobandrena) funerea Warncke, 1975, female G propodeum, dorsal view; Andrena (Truncandrena) ferrugineicrus Dours, 1872, female H propodeum, dorsal view.