Species 4a. C. columbiensis Wülker, Sublette, Morath & Martin, 1989

Adult

Male:  (based on South American specimens)
Wing length 2.59 (2.47-2.70) mm; venarum ratio 1,03
Antennal ratio 2.2 (2.1-2.4).
Leg ratios: Ant. - 1.76 (1.73-1.80): Mid - 0.64 (0.61-0.67); Hind- 0.76 (0.75-0.77); Beard ratio: 2.08 (2.0-2.2).
Whole body yellow-brownish with darker markings, middle and lateral mesonotal vittae separate, scutellum pale.  All femora with a narrow apical dark fascia, the basal third of fore tibiae dark, in middle and hind tibiae bases only slightly infúscate; tarsomeres 1-4 with an apical dark fascia.
Abdominal segment I with broad median fascia, II-IV with saddle-shaped fasciae, V and VI with longitudinal oval dark spot, VII darker than the light segment VIII.
Head:  Palpal proportions (segs 2-5, µm) 58 : 225 : 228 : 297.  Clypeus with 29 (26-33) setae; frontal tubercles 30 µm long, 9.2 µm wide.
Thoracic setae:  dorsolateral 28.8 (24-35), acrostichal 12.8 (10-19) in double row, prealar 5, scutellar 30.8 (24-40).

Male terminalia of C. columbiensis
with superior volsella variants (center)

Genitalia: Anal point parallel sided, in its middle slightly widened, terminally rounded; upper volsella comparatively long, straight, but dorsally curved, blunt-tipped, basal lobe with remarkably strong bristles; lower volsella parallelsided, reaching to the middle of gonostyle.    Setae of anal tergite 10.4 (8-13), gonostyle inner bristles 4.5 (4-5).

Similar to C. anonymus Williston.  Best distinguished by the lower AR (2.1-2.4 in South America).

Pupa: not described.

Fourth instar larva:  a medium-sized (abt. 9-14 mm) (females 12.04, 11.2-14.0) plumosus-type with well developed lateral (0.4-0.6 mm) and ventral tubules, posterior pair of VTs longer (ant VT 0.32-2.32 mm; post VT 0.48-3.12 mm) with a cline in size from north to south (from 1 mm, constriction in middle in Florida, to less than 200 µm in Guatemala).
Gular region may be slightly darkened only on the posterior edge or pale; dorsal head sometimes with slight darkening paralleling the frontoclypeus near its posterior end, but mostly pale.
Mentum (Fig. c) with 4th laterals reduced to level of 5th laterals, c1 tooth moderately broad with c2 teeth well developed (type II).
Ventromentum (Fig. d) with about 40-42 striae.  Pecten epipharyngis (Fig. a) with about 13-14 teeth.  Premandible with inner tooth broad, about 3.5 times wider than the inner tooth, both coming to relatively broad points (type C).
Antenna (Fig. b) with relatively long narrow basal segment, almost 4.5 times longer than wide; AR about 1.8; ratio of segments (microns) 120 ; 34 ; 9 ; 13 ; 6 .
Mandible (Fig. e) with third inner tooth pale and only partially separated (type IIB); about 22 furrows on outer surface at base; about 12-13 taeniae in PMa; Mdt-Mat about 28, MTR about 0.38.

Cytology:  Four polytene chromosomes with the columbiensis-cytocomplex combination: AG, BF, CD, E.
Nucleolus on arm G near the centromere.  Arm G also with two BRs, one near middle of the arm and another near the distal end.
No polymorphism yet found in North American populations, but heterozygosity of arms A and B was found in a Guatemalan population (Wülker et al., 1989b).
colA1:    1a-e, 6c - 4, 10 - 12, 6d - 9, 2d - 3b, 2c - 1f, 3c-i, 13 - 19 (inv 12-6c from anonymus)
colB1:    Large puff (group 7) near centre of arm with distal dark bands (group 8)
colC1:    The typical dumb-bell (group 4 plus parts of 3 and 5) is about one third from centromere
colD1:    proximal & distal segments identical to anomymus, but intermediate region differs by at least 3 inversions
colE1:    1 - 2, 9 - 10b, 3e-a, 8 - 3f, 10c - 13                                as anonymus E1
colF1:    1, 16 - 19, 6b - 2, 15 - 14, 12 - 13, 6c - 11, 20 - 23            as anonymus F1
colG1: differs by a proximal and a distal inversion from that of anonymus G1

Found: Florida - Grassy Key, Munroe Co. (Hribar et al., 2008)
            Virgin Islands (USA) - Lameshur Bay, St. John Island
            Guatemala - Jocotan, Chiquimula
            This species has also been found at San Fernando (Cali), Colombia (type locality)

            So far found in man-made habitats, in Colombia associated with algae.

The banding sequences of arms A, E and F were described by Wülker & Morath (1989) as C. spec. Cali.    The species was described for adult male, larva and the polytene chromosomes pictured by Wülker et al. (1989b).