Ceratina (Zadontomerus) mikmaqi Rehan & Sheffield

Rehan, Sandra M. & Sheffield, Cory S., 2011, Morphological and molecular delineation of a new species in the Ceratina dupla species-group (Hymenoptera: Apidae: Xylocopinae) of eastern North America, Zootaxa 2873, pp. 35-50 : 39-43

Ceratina (Zadontomerus) mikmaqi Rehan & Sheffield , new species

Diagnosis. Males of C. mikmaqi can be recognized by the combination of the metallic greenish blue colour, T3 with punctures separated by> 1 puncture diameter, and the hind femur which is only slightly dilated toward base, the lower margin carinate only in the apical half. They are very similar to C. floridana and C. dupla . Males of C. floridana have T3 densely punctate, with interspaces ≤ 1 puncture diameter, and the carina of T7 is more truncate. Males of C. dupla have a complete carina running the length of the hind femur.

Females of C. mikmaqi are recognized by the combination of the metallic greenish colour, the small basal ivory spot on the front tibia, the largely impunctate surface in the posterior half of the mesoscutum, and the clypeus which has an elongate, median maculation, and sinuate lateral edges. They are very similar to C. dupla and C. calcarata . Females of C. dupla have distinct rows of punctures medially on the posterior half of the mesoscutum. Females of C. calcarata have the lateral edges of the clypeus more angulate, and often have the clypeal maculation greatly reduced or absent.

Description. FEMALE. Length 6–8 mm; head length 1.67–2.22 mm; head width 1.75–2.04 mm; forewing length 4.63–5.3 mm.

Colouration. Body mostly bluish green. Mesoscutum often black with violet reflections centrally. T1 largely black. Apical half of clypeus, malar area, basal half of mandible, lower paraocular area, and genal area adjacent to eye margin black. Antenna dark brown to black, flagellum with ventral surface reddish brown. Tegula reddish brown. Wing membrane subhyaline, venation and pterostigma dark brown. Legs bluish green, tibia and tarsi dark brown to black, distitarsus and tarsal claw reddish, all spurs yellowish brown. Clypeus with a pale, vertically elongate, median maculation. Posterior half of pronotal lobe with pale maculation. All tibia with a small, pale basal maculation.

Pubescence. Dull white. Very sparse and mostly short (≤1 OD). More elongate (1.5–2 OD) on vertex, frons, labrum, metanotum and mesopleuron, on legs, and basal sterna, with a few very long (>3 OD) hairs on the apical sternum.

Surface sculpture. Body in large part polished and shiny. Clypeus polished, with large, well spaced (i=1–3d), elongate punctures in apical half, punctures becoming rounded and smaller basally. Supraclypeal area with large, well spaced (i=1–2d) punctures apically, becoming much finer and dense (i≤d) between antennal sockets. Lower paraocular and antennocular area punctation rather dense (i=1–1.5d). Upper paraocular and ocellocular areas with punctation sparser (i=2–3d), becoming closer (i=1–1.5d) on vertex. Frons with swellings largely impunctate, punctures fine and close (i≤d) adjacent to median ocellus. Gena above with punctation close (i=1–1.5d), punctures elongate, becoming sparse (i>3d) to virtually impunctate below and adjacent to eye. Mesoscutum polished, punctation coarse, moderately dense (i=d) anteriorly and along lateral and posterior margins, largely impunctate medially, with irregularly spaced punctures along medial line and parapsidal lines. Mesoscutellum similar to mesoscutum, submedial punctation moderately sparse (i=1–3d). Axilla and metanotum with punctation fine and close (i=d). Tegula largely impunctate, with very fine, close (i<d) punctures on inside margin. Pronotum with punctation fine and close (i=d), with small impunctate area anterior to pronotal lobe. Pleural punctation course and close (i=d) throughout, punctures becoming slightly sparser (i=1.5d) below. Metapostnotum largely tessellate apically, with strong, well spaced striae basally. Propodeum finely and densely punctate throughout (i≤d). T1 largely shiny and impunctate, often with a few fine, sparse (i=2–3d) punctures at apicolateral edge, and with with a triangular area of coarser, closer (i=d) punctures apicomedially, T2–T4 punctation more coarse, quite deep and distinct, close laterally (i≤ 1d), becoming well separated (i=2–3d) medially, punctures on apical edge of T2 and T3 becoming finer (i≤ 1.5d), T4 becoming irregularly roughened in apical half, though with punctures visable to apical edge, T5 rugose, without distinct punctures except on apical edge, T6 entirely rugose; all sterna coarsely and closely punctate (i<d), punctures becoming slightly separated (i≤d) laterally on S2–S4.

Structure. Head width varying (length/width ratio = 0.95–1.09). Eyes with inner margins subparallel to slightly converging below. Clypeus inverted T-shaped, 1/3 below suborbital tangent, apicolateral margins broadly rounded. Antennal sockets evenly spaced (IAD=AOD). Gena narrower than eye (0.54–0.8). Hypostomal carinae parallel, reflexed distally. Mandibles 3-dentate, with median tooth larger and longer than 1st and inner teeth. F1 longer than broad (1.5:1), nearly as long as F2+F3, F2–F5 broader than long, F6 quadrate, remaining flagellomeres slightly longer than broad. T6 apical margin coming to a fine triangular point.

MALE. Similar to female except for the usual secondary sexual characters and as follows. Length. 5–7 mm; head length 1.3–1.48 mm; head width 1.38–1.57 mm; forewing length 3.7–4.1 mm.

Colouration. As in female except tibia typically dark blue; labrum with a large, pale central maculation; clypeal maculation inverted T-shaped, large, filling most of surface.

Pubescence. Generally as in female, except long hairs (2 OD) present laterally on T4–T7, on apical margin of S2– S5. T6 with apex of process with a tuft of dense, short, yellowish pubescence. Carina of T7 laterally with elongate (2 OD) yellowish hairs.

Surface sculpture. Generally as in female. T6 entirely rugose; T7 more distinctly punctate basally, surface of carina smooth and sparsely punctate; all sterna coarsely and closely punctate.

Structure. Head round to slightly elongate (length/width ratio = 0.94). Eyes strongly convergent below (UOD/LOD ratio = 1.2–1.3). Clypeus inverted T-shaped, 1/3 below suborbital tangent, apicolateral margins broadly rounded. Antennal sockets slightly separated (IAD/OAD=1.2). Gena narrower than eye (2:3) in smaller specimens, to wider than eye (4:3) in larger ones. Hypostomal carinae parallel, reflexed distally. Mandibles 2-dentate, with upper tooth larger and longer than 1st tooth. F1 quadrate to very slightly longer than broad, F2–F5 broader than long, F6 quadrate, remaining flagellomeres slightly longer than broad. Hind femur somewhat dilated toward base but not angulate, the length more than twice the width, the lower margin carinate only in the apical half. T6 with a prominant rounded medial process overhanging the apical margin of T7. T7 with a wide, broadly rounded to subtruncate carina. Apical margin of S6 with a deep median cleft, lateral margins bent ventrally. S7 and genital armature as in C. dupla and C. calcarata (see Mitchell 1962).

Etymology. Ceratina mikmaqi is named in honour of the Mi’kmaq, the First Nations People of Nova Scotia where this species was first discovered with DNA barcoding (Sheffield et al. 2009).

Type material. The male holotype of C. mikmaqi was collected in Middleton, N44.9665, W65.5755, Annapolis Co., Nova Scotia, Canada on 20.vi.2002, col. Cory Sheffield [ DNA barcode sample ID “02-NS-1619”]; the specimen is in good condition, but missing the right antenna and middle leg. The female allotype was collected in Forest Home, N44.9117, W64.5288, Kings Co., Nova Scotia, Canada on 2.vii.2003, cols. C. Sheffield, S. Rigby, and K. Jansen [ DNA barcode sample ID “sheffT-58”]; the specimen is in excellent condition, but missing the right hind leg. Both holotype and allotype are in the Packer Collection at York University ( PCYU).

Paratypes were designated from the following locations: CANADA: NS; Avonport, N45.119, W64.273, Kings Co., 21.vi.2001 [3; “01-NS-1622”], col. Cory Sheffield; East Torbrook, N44.927, W64.93, Kings Co., 20.vi.2002 [3; “02- NS-1618”], col. Cory Sheffield; Somerset, N45.0836, W64.7322, Kings Co., 22.vi.2001 [3; “sheffT-62”], col. Cory Sheffield; West Black Rock, N45.13, W64.74, Kings Co., 5.vi.2002 [3, “02-NS-1621”], col. Cory Sheffield; ON; Cambridge, Shade`s Mills Conservation Area, N43.38, W80.284, 12.vii.2007 [Ƥ, “G5S-20070712-002”], 30.viii.2007 [Ƥ, “G5B-20070830-001”], 23.vii.2007 [3, “ O 1Y-20070723-006”], col. M. Horn; Waterloo, Chesapeake Drive, N43.508, W80.505, 01.vii.2008 [3, “N3Y-20080701-005”; Ƥ, “N3Y-20080701-006”]; St. Catharines, Brock University Campus, N43.119, W79.249, 1.viii.2008 [Ƥ, “08-ON-2151”]; 3.viii.2008 [Ƥ, “08-ON-2146”]; 14.viii.2008 [2Ƥ, “08-ON-2150”, “08-ON-2147”], col. J. Vickruck; UNITED STATES: MD; N38.909, W76.683, Pr. George’s Co., 18.vi.2009 [Ƥ, “CCDB-01570 D03’], col. S.W. Droege; NE; N41.2774, W95.9116, Douglas Co., 10.v.2007 [3, “CCDB-01570 F11”], col. S.W. Droege; NY; N41.029, W72.138, Suffolk Co., 07.ix.2005 [Ƥ, “CCDB-01570 E03”], col. S.W. Droege; KY; N36.924, W84.872, Wayne Co., 27.vii.2007 [Ƥ, “CCDB-01570 B06”], col. S.W. Droege; WI; N43.338, W89.949, Sauk Co., 5.ix.2007 [4Ƥ, “CCDB-01570 D08 – D11”], col. M. Mossman. Paratypes are in the Packer Collection at York University ( PCYU).

Distribution. Ceratina mikmaqi ranges in Canada from Nova Scotia to southern Ontario, and south into the northeastern United States, as far west as Nebraska, and south to Kentucky. Its range overlaps that of C. dupla and C. calcarata (see Mitchell [1962] and Daly [1973]).