Comparison of Larval Characters of Exotic and Native Stegomyia/Ochlerotatus Mosquitoes in New Jersey

Jamesina Scott, Mosquito Research and Control, Dept Entomology.

(Jamie is now at Placer County Abatement District, California)

 Figures (photos) are shown below table.

Exotic Stegomyia/Ochlerotatus mosquitoes Native Ochlerotatus mosquitoes 

St. albopictus

Oc. japonicus

Oc. atropalpus

Oc. triseriatus

Upper & lower head hairs

Single (upper head hair may be double or triple) and in a box arrangement

Multiple and in a straight line (Fig. 1)

Single and in a box arrangement. (Fig. 2)

Single (upper head hair rarely double) and in a box arrangement

Anal gills

Equal and blunt (sausage-shaped)

Equal and tapering

Equal and tapering

Unequal and blunt

Anal saddle

Smooth

(Fig. 4)

Conspicuously spiculated

(Fig. 3)

Smooth or weakly speculated.

(Fig. 4)

Smooth

(Fig. 4)

Lateral hair
  • Originates on the anal saddle.
  • Usually double (rarely 3-5 forked).
  • About equal to the length of segment X.
  • Originates on the anal saddle.
  • Single (rarely double).
  • Longer than the length of segment X
  • Does not originate on the anal saddle.
  • Single.
  • Shorter than the length of segment X
  • Originates on the anal saddle.
  • Multiple.
  • Shorter than the length of segment X
Comb scales Aligned in a single, neat row In a patch In a patch In a single, or partly double row.  Never aligned in a neat row.
Siphonal tuft
  • Usually 2-4 branched.
  • Inserted beyond row of pecten teeth
  • Tuft (4-7 branched).
  • Inserted within row of pecten teeth
  • Tuft (4-9 branched).
  • Inserted within row of pecten teeth
  • Single, double, or rarely triple.
  • Inserted beyond row of pecten teeth

 

Figure 1. The upper and lower head hairs of Ochlerotatus japonicus larvae are multiple (tufts) and arranged in a straight line.

Ochlerotatus japonicus
Figure 2. The upper and lower head hairs of Ochlerotatus atropalpus larvae are single hairs that are arranged in a "box-like" formation.

Ochlerotatus atropalpus
Figure 3. A spiculated anal saddle.

Ochlerotatus japonicus
Figure 4. A smooth anal saddle.

Ochlerotatus atropalpus