Among different type of polymorphism, color polymorphism provides one of the best characterized examples of functionally and ecologically important polymorphisms. In many animal groups, color polymorphism differentially affects the adaptations of the individuals in the populations. Warning coloration is considered as an important factor against natural enemies in many animals [1].

Some color morphs in species may be more cryptic than other morphs and therefore becoming harder for predators to locate them visually. Examples of these cryptic morphs to reduce the risk of predators have been reported in vertebrates and invertebrates [2,3].

Polymorphism have been reported in different groups of insect such as dragonflies [4,5], aphids [6,7], Diptera [8-10], Lepidoptera [11], ants [12], bees [13], coccinellids [14-17].

Lady bird beetles are voracious familiar predators of aphids, scale insects, and many other pests in orchards, farmlands and pastures [18,19]. Some of lady bird beetles have brightly colored and these colors are a warning signal to their natural enemies. This signal is addressed to optically orienting predators [20]. The lady beetles have dotted patterns, which these patterns are differently in different individuals. Most common colors used by insects to discourage predators from attacking them are bright red, orange, and yellow [21]. Dolenska [22] suggested that lady bird beetles with a spotted pattern were attacked less frequently than unspotted ones and when they had removed elytra.

Hippodamia variegata Goeze has a wide distribution range in the Palearctic and extends to Nearctic areas [23]. This species is widespread in Iran and usually undergo 2-3 generations per year [24-30]. This predator is associated with diverse herbaceous plants [31]. Under suitable conditions of temperature and food supply this predator is active year around and otherwise overwinters as adult [32]. Hence, H. variegata has important role in control of crop pests such as aphids. The purpose of the present study was to investigate the color polymorphism of H. variegate in Chegini regions, Lorestan province, Iran.

The Collection of specimens was conducted from various regions of Chegini region, Lorestan province, Iran. Different morphs of H. variegate were collected from five localities including: Shorab, Sarab Doreh, Kashkan and Viesian (Situated between 31° 32’ to 31° 40’ N and 48° 02’ to 54° 26’ E).

Each locality was repeatedly sampled throughout 16 month (from April, 2012 to August, 2013). Specimens were collected from agricultural and non-agricultural landscapes. Adult specimens were collected with a standard sweeping net and by hand. Insects were killed in a cyanide bottle. In order to preserve quality including appearance and color as well as image quality samples were kept inside the closed bottles at sub-zero temperatures. Specimens were identified to species level with the help of available literature and characteristics of male genitalia (Figure 1).

Figure 1: Distinctive characters of Hippodamia vareigata Goeze: 1. maxillary palpus securiform, 2. Antenna long (11-segmented), 3. mandible bifid at apex, 4. Tarsus cryptotetramerous and each tarsal claw cleft near apica, 5. Tegmen in ventral view 6. Sipho, 7. Ist abdominal sternum.

Different morphs were identified based on morphological characteristics including color and spots on dorsal surface of the elytra and pronotum.

Results showed that H. variegata was found at all five sampling localities in Chegini region (Lorestan province, Iran). A total of 500 specimens were collected from five sites and 18 morphs of H. variegata were identified. Results showed that in all 18 collected morphs a blfiack spot is located in the middle of scutellum.

Different morphs of H. variegata are as follows:

Elytra red, with 11 black spots (Figure 2A); Elytra red, with 13 black spots (Figure 2A and 2B); Elytra red with 7 black spots (Figure 2A and 2C); Elytra red, with 11 black spots (Figure 2D); Elytra are red with 9 black spots (Figure 2E); Elytra are red with 5 black spots (Figure 2F); Elytra are orange with 9 black spots (Figure 2G); Elytra are red with 9 black spots (Figure 2H); Elytra orange, 7 black spots (Figure 2I); Elytra are red with 7 black spots (Figure 2J); Elytra are red with 15 black spots (Figure 2K); Elytra are red with one black spot (Figure 2L); Elytra are red with 11 black spots (Figure 2M); Elytra are red with 13 black spots (Figure 2N); Elytra red to orange, 9 black spots (Figure 2O); Elytra are red with 9 Black-spotted (Figure 2P); Elytra are red with 13 black spots (Figure 2Q); 3.18. Elytra are red with 9 black spots and 1 black stripe (Figure 2R).

Figure 2: Different morphs of H. variegata in Chegeni region, Lorestan province, Iran.

The color pattern of the elytra and of the pronotum is very widely variable in many species of lady bird beetles. Morphs of lady bird beetles have different appearance such as number, size, color and pattern of spots on elytra and pronotum. In most cases the occurrence of morphs appears to be associated with climatic factors, industrial pollution and, possibly, visual predation [33]. Polymorphism of several coccinellids, such as Adalia bipunctata (L.) and A. decempunctata (L.) has been studied [34,35]. Zare [17] reported that 17 different morphs of A. bipunctata in Mehriz region of Yazd province, Iran.

The variegated lady birde beetle, H. variegata has been reported as an important natural enemy to at least 12 different aphid species. This species is widespread in the world and can be used as an important biological agent for control of pests. The present study is an attempt to identify different morphs of H. variegata in Lorestan province, Iran. Although genetic studies can provide important information for identify different morphs of one species.