Andrena nimigracilis, a new species (Hymenoptera: Andrenidae) from México Author Zabinski, Wyatt J. Department of Ecology and Evolutionary Biology, 1200 Sunnyside Avenue, University of Kansas, Lawrence, KS 66045, USA (zabinski @ ku. edu) text Journal of Melittology 2024 2024-09-18 2024 118 1 9 journal article 10.17161/jom.i117.22244 2325-4467 14670010 urn:lsid:zoobank.org:pub:4CA64A4D-CEF7-4409-AFC4-415D414815D7 Andrena nimigracilis Zabinski , new species ZooBank: urn:lsid:zoobank.org:act: DE02888C-C4C0-4F92-81D2-C8702B6DDFCD ( Figs. 1–6 ) Figures 1–3 . Main features of the holotype of Andrena nimigracilis , new species . 1. Lateral view of head showing narrow gena, as indicated by the arrow. 2. Lateral view of declivitous propodeum, as indicated by the arrow. 3. Dorsal view of thin abdomen. Figures 4–6. Holotype of Andrena nimigracilis , new species . 4. Facial view. 5. Dorsal habitus. 6. Lateral habitus. DIAGNOSIS: The new species, known only from the male, most closely resembles the male of Andrena ( Celetlandrena ) vinnula LaBerge & Hurd, 1965 . Both species share a declivitous propodeum, forewing with 1 st m-cu vein meeting second submarginal cell at about two thirds distance from base of cell, maxillary palpus exceeding galea by at least last three segments, clypeus protruding beyond eyes, pronotum with humeral angle, first flagellar segment slightly longer than segment 2, long antennae extending past tegula, pale yellow/cream colored clypeus, and sternum 6 not reflexed. Andrena nimigracilis differs from that species in having an extremely weak humeral angle, a gena narrow (0.53 ˟ width of compound eye), an abdomen extremely narrow (narrower than thorax, with T1 longer than broad), compound eyes wide compared to length (width=0.5 ˟ length), propodeum coarse, labial palpus segment 1 flattened, as long as succeeding segments combined, and vertex ≤ 1.5 ˟ lateral ocellar diameter. DESCRIPTION: Male. Measurements: Orientation dorsal: total length, 6.58 mm ; greatest width (of entire specimen is head), 1.85 mm ; intertegular distance, 1.12 mm ; thorax length, 2.23 mm ; thorax width, 1.54 mm ; abdomen length, 3.95 mm ; abdomen greatest width, 1.28 mm ; forewing length, 4.42 mm . Orientation front of face: head width, 1.97 mm ; head length, 1.62 mm . orientation lateral-dorsal: antennae length, 2.92 mm Integument Color: Black except as follows, abdomen and legs brown rufescence; wing membranes hyaline to very lightly infumate; ocelli brown, eyes brown; clypeus pale yellowish to cream; tibial spurs same color as wing membranes. Structure: Antenna long, extending past tegula posteriorly; scape subequal to flagellar segments 1, 2, plus half of 3; flagellar segment 1 slightly longer than segment 2, subequal in length to all but apical segment, which is slightly longer. Compound eye twice as long as broad in lateral view; inner eye margins converging slightly inferiorly, interocular distance greatest in upper half. Malar space linear, about 5 times as long as broad. Mandibles edentate, without ventrobasal lamella, and two strong lateral carina from base to apex. Galea short, shorter than clypeus; shiny with fine micro reticular shagreening. Maxillary palpus exceeds galeae by about last 3 segments; segments 1, 3, 4, and 6 subequal; segment 2 longest, 5 shortest, and 4 much thinner proximally. Labial palpus segment 1 curved, flattened, and subequal to 2–4 combined; segment 4 subequal to 2 and 3 combined; segments 2 and 3 subequal. Labral process small and obcordate. Clypeus with idents on margins medially, shortest at apex, and widest at base, protruding beyond eye in lateral view; shiny, with dense reticular shagreening, and sparce scattered punctures from base of setae. Supraclypeal area shiny, raised, and faintly rugose. Eyes distinctly broader than genal area, about twice as broad in lateral view; genal area with light scattered punctures and shiny. Vertex ≤ 1.5 ˟ lateral ocellar diameter; vertex and frons with dense strong shagreening. Facial fovea thin and shallow. Strong carina from apex of supraclypeal area to base of median ocellus; carina starts progressively weakening at upper third distance to apex. Pronotum with extremely weak humeral angle and dorsoventral ridge; covered by coarse dense reticular shagreening. Mesoscutum with dense shallow punctures, separated by less than 1 puncture width, weakly rugose at none separated punctures. Tegulae shiny with sparce punctures. Mesoscutellum same as mesoscutum but with punctures less dense medially and at apex. Metanotum same as mesoscutum but more rugose with oval shaped punctures. Propodeum coarsely sculpted, coarsest within propodeum triangle; propodeum triangle strongly rugose anteriorly, anterior and medial rugose are long, diagonal and horizontal, and posteriorly fades to shorter rugose; rest of propodeum with dense finely rugose punctures forming ridges throughout. Mesepisternum same as propodeum covered in dense connected or nearly always connected finely rugose punctures throughout. Metepisternum like mesepisternum and propodeum but with shallow less dense oval punctures and less rugose. Middle basitarsus thin, same width throughout; slightly thinner than hind basitarsus; hind tibia much wider distally, at least 2–3 times wider; middle tibia wider distally but not as extreme. Hind tibial spurs straight, middle tibia spur nearly straight, and fore tibial spur slightly bent medially with lamella extending from near base to medial bend. Pretarsal claws with tooth on all legs. Wings stigma broadest medially; prestigma about half width of stigma; stigma 3 times or more length of prestigma; 3 submarginal cells; 1st m-cu vein reaches second submarginal cell at about two thirds distance from base of cell or closer to 2 rd transcubital vein than to 1 st . Metasomal tergum 1–5 all shiny. Terga 1 with extremely sparce minute punctures, separated by puncture diameter of 3 or more. Terga 2–4 apically with dense long honeycomb surface, medially with fine tessellation, and punctures separated by 2–3 puncture diameters. Terga 5 same as 2–4 but lacking apical honeycomb textured surface. Sternum shiny; sternum 1–4 covered in fine tessellation, strongest apically, and sparce punctures separated by 3 or more punctures diameters; sternum 5 same as 1–4 but tessellation weak, not strongest apically; sternum 6 not reflexed. Genitalia was not examined to avoid damage to other parts of the specimen. Vestiture: White throughout, hairs on head, thorax, and femur of foreleg long and highly plumose. Rest of body, hairs are generally short and simple, with an occasional long and plumose hair. Terga without apical fasciae and sterna without distinct apical bands of long hair. HOLOTYPE : Male, México , Michoacán , San Juan Nuevo, 31-X-1987 , 1800m , Col. L Godinez , LG-259. SM0295750 KUNHM-ENT . Deposited at the Snow Entomological Museum Collection ( SEMC ) at University of Kansas in Lawrence, Kansas. DISTRIBUTION: Only known from type locality. FEMALE: Unknown. ETYMOLOGY: The name of this species is derived from the two Latin words Nimis , meaning too, too much, or excessively, and Gracilis , meaning thin or slender, emphasizing the uniquely narrow abdomen of this species. Addition of Andrena nimigracilis to the key to the subgenera of Andrena of North and Central America (Males) ( LaBerge, 1985 ; Michener, 2007: 248–251 ). 18(17). Propodeum with lateral surface separated from lower posterior surface by short lateral carina; antennae short, female-like, usually not extending past tegulae ...............................................................................................( Hesperandrena ) − Propodeum with lateral surface not at all separated from lower posterior surface by a carina; antennae long, extending past tegulae................................68 68(18). Genal area narrower than eye in lateral view; abdomen abnormally narrow, 3 times as long as wide.............................................................( Andrena nimigracilis ) − Genal area broader than eye in lateral view; abdomen narrow but not abnormal, less than 2.5 times as long as wide.....................................................( Celetandrena )