New Jersey Butterfly Club

Spring Azure

Celastrina ladon

Identification: Very small—about 1”. Above: Male FW and HW bright blue, whereas female is duller blue with prominent black FW margin. Below: FW and HW grayish, with darker markings. Three different forms fly at the same time in the spring, differentiated by markings on the HW below: Form "violacea" has scattered dark spots. Form "marginata" has dark gray-brown borders on FW and HW. Form "lucia" has a prominent dark splotch in the middle of the HW as well as dark borders on both wings. Similar species: Spring Azure is actually a complex of many forms, some of which may be subspecies or actual species in their own right. NABA presently recognizes only 'Summer' and 'Atlantic' Azures as subspecies, based on appearance, flight times, and food plants. Both are paler both above and below than Spring Azure, and almost always occur as form "violacea," with very small spots below. Best distinguished by location, flight time, and association with food plant (see below).

Spring Azure form "violacea" is essentially indistinguishable from Appalachian Azure (see account for that species). Eastern Tailed-Blue resembles form "violacea" below, but is slightly smaller, and has orange spots and tiny tails at outer angle of HW. Flight is weak and usually fairly low to the ground, whereas Azures will fly strongly up into shrubs and lower tree branches. Spring Azure can also be confused with the Bluish Spring Moth (Lomographa semiclarata), which flies during the day and often lands on moist soil. This weakly-flying moth is smaller than an azure and paler below, shows no blue above, and has a single black spot in the center of each wing below.

NJ Status and Distribution: Resident. Spring and 'Summer' Azures are common and widespread. 'Atlantic' Azure occurs on the Coastal Plain only, where it is also common and widespread.

Habitat: Spring and 'Summer' Azures inhabit woodland edges and openings, and readily visit garden flowers. 'Atlantic' Azure is found in forested areas, often near bogs and cedar swamps.

Flight Period: Spring Azure: A single brood from mid-March to about early June. Extreme dates: North Jersey 3/14—(late date uncertain owing to overlap with emergence dates of other azures). South Jersey: Spring Azure 1/10—5/17. 'Atlantic' Azure has a single brood, flying between the extreme dates of 3/12—6/23. 'Summer' Azure: Several broods from about late May to late October. Extreme dates: North Jersey (Early date uncertain owing to overlap with end of Spring Azure flight period)—11/27. South Jersey 3/8—11/14 (according to South Jersey butterfly group data).

Caterpillar Food Plants: Spring Azure: Primarily buds of Flowering Dogwood (Cornus florida) but also of blueberries, viburnums, and possibly others. 'Summer' Azure: Mainly flowers of shrub dogwoods, but also reported from many other plants. 'Atlantic' Azure: Hollies—in NJ, Inkberry (Ilex glabra) and American Holly (I. opaca).

Overwintering Stage: Pupa.

Good Locations: Spring and 'Summer' Azures: Anywhere and everywhere. 'Atlantic' Azure: Warren Grove RA.

Comments: All it takes for a spirited argument are 2 taxonomists and 1 azure. Various researchers recognize many species in the "Spring Azure Complex," including 'Summer' Azure, 'Northern' (aka 'Blueberry') Azure, 'Cherry Gall' Azure, and 'Holly' (aka 'Atlantic,' 'Atlantic Holly,' or 'Pine Barrens') Azure. For further information on this complicated topic, see Cech and Tudor, Butterflies of the East Coast; Gochfeld and Burger, Butterflies of New Jersey; and a technical paper by Wright and Pavulaan (1999) describing 'Holly' Azure as a new species.