crossvein

crossvein

[′krȯs‚vān]
(mining engineering)
A vein that intersects an older or larger vein.
References in periodicals archive ?
Ptecticus aurifer group: Upper frons, median occipital sclerites and vertex yellow; wings bicolored or more or less darkened; scutum uniformly yellow to brown; M3 slightly sinuated, CuP (postcubitus) well developed, pigmented; vein R2+3 slightly sinuate, shorter than Rs, radial triangle (r2+3) higher than crossvein R-M, crossvein M-Cu well developed.
It is characterized by the stalked ocelli and compound eyes, pronotum with umbelliform process dorsally, not concealing the scutellum or the forewings in repose; the forewing and hindwing with one r-m and one m-cu crossvein; tibiae not foliaceous; metatibiae with cucullate setae in row II, first tarsomere has one cucullate setae apically and the abdomen without conspicuous punctuation (Deitz, 1975; Flynn, 2014).
Wings light brown hyaline, posterior crossvein slightly infuscate, length 4.6 mm (3.9), length to width ratio = 2.5 (2.4).
Forewing with crossveins absent in costal area; basal cell large; ScP+RA (branch ScP+RA forked from RP in proximal third of wing), RP 3; 2 r-m crossveins; MP 7-9 branched (1st M fork just distad of 1st R fork), following a proximal nodal cell C3, postnodal media cells divided into distal and proximal cells by 6 or 7 im crossveins in a post-nodal line; 1 m-cu crossvein; CuA and CuP usually simple; C5 absent or very distally and open; clavus long, open; Pcu reaching A1 past distal third of wing in apical portion of clavus; 1-4 transverse veins CuP and Pcu near apex of clavus; A1 arched to follow contour of postclaval margin, creating narrow (and usually darkened) cell between A1 and trailing margin of wing.
Wing: Length is measured from the humeral crossvein to tip, breadth at the level of the r-m crossvein.
The genus can be recognized mainly by all femora with spine-like antero- and posteroventral setae; setae on fore femur distinctly stronger than those on mid and hind femora; mid and hind legs longer and more slender than fore leg; vein [R.sub.2+3] sinuous just before margin; crossvein r-m at distal three-fourths of cell dm; metastemum bare; and postcoxal metathoracic bridge completed (Carvalho et al.
According to this author "the differences [of bintoniellidaeans with respect to vitimiidaeans] are only that the base of CuA1 [CuPa[alpha]] disappeared [....] and became a crossvein so that the stem of MP + CuA1 [CuA + CuPa[alpha]] branches from M".
Wing length was taken from the intersection of the wing margin and vein III to the intersection between this vein and the anterior crossvein. Finally, the length of the posterior crossvein was measured.