EXTERNAL MORPHOLOGY OF GRASSHOPPER ABSTRACT Morphology is inherent to an understanding of how insects live and function. Orthopteroid insects are good choices for this study because gross morphological features are readily observed. Like most other insects, the grasshopper (or other Orthopteroid) consists of three general body regions: the head, thorax and abdomen. For morphological studies, antennae were detached from the specimen. Then, the antenna was mounted in a glass slide. The prepared slides were then examined under magnoscope for studying the anatomical features. The grasshopper was illustrated and each part was properly identified. The most obvious and distinctive features of grasshoppers are their enlarged hind legs and their relatively short, thick antennae. The morphology of insects enables the phenomenal success of this class of arthropods. The high rates of speciation, short generations, and long lineage have caused insects to evolve in many ways, resulting in very large variations in morphology. Keywords: morphology, Orthopteroid, speciation, lineage, variations
INTRODUCTION Morphology is inherent to an understanding of how insects live and function. In contrast to anatomy which is the naming and description of the structural features of an animal, morphology includes the manner in which the parts have been derived, how they function and how they interrelate with similar structures in closelyrelated animals. Orthopteroid insects are good choices for this study because gross morphological features are readily observed. Orthopteroids are considered primitive and demonstrate the basic body plan of most insects. Like most other insects, the grasshopper (or other Orthopteroid) consists of three general body regions: the head, thorax and abdomen. The abdomen is further subdivided into numerous somites and segments which are readily observed in the Orthopteroids but are often obscured in other insects. (Hariri, et al., 2001) This study aims to observe and identify the different morphogical features of
grasshopper collected from PUP – Sta. Mesa, Manila Oval.
METHODOLOGY The grasshoppers were collected from the PUP – Sta. Mesa, Manila Oval by using hand net. The specimens were killed using sacrificing agent in a wide mouth bottle. For morphological studies, antennae were detached from the specimen. Then, the antenna was mounted in a glass slide. The prepared slides were then examined under magnoscope for studying the anatomical features. The grasshopper was illustrated and each part was properly identified.
RESULTS AND DISCUSSION
Figure 1. Grasshopper
The most obvious and distinctive features of grasshoppers are their enlarged hind legs and their relatively short, thick
antennae. The tegmina are another distinctive feature, but only in winged species.
Figure 2. Filiform-type of antenna of the grasshopper
Based from the observation under the microscope, it only shows that it has a filiform type of antennae. The appendages found on the head are the antennae and their mouthparts. Antennae functions in sensory reception while their mouthparts consist of mandible (jaws) and maxilla which is located behind the mandibles to cut and hold the food. Thoracic appendages are composed of wings (forewings have a leathery appearance that protects the hind wing) and legs (wherein the first two legs are for walking and its last two pairs are for jumping). Male grasshoppers have thinner tail, smaller size and their abdomen is rounded and dips into subtle curve before tapering at a slightly raised angle. While female grasshoppers have bigger tail, bigger in size and their abdomen is straight with no curves and its legs are long by a few millimeters.
CONCLUSION AND RECOMMENDATION The morphology of insects enables the phenomenal success of this class of arthropods. The sheer quantity and diversity of its taxa are matched by a large variation of modifications in its body structure. The high rates of speciation, short generations, and long lineage have caused insects to evolve in many ways, resulting in very large variations in morphology. These modifications allow insects to occupy almost every ecological niche, use a staggering variety of food sources, and possess diverse lifestyles. After conducting this descriptive study, it is recommended to use grasshoppers as a good choice for this
study because gross morphological features are readily observed. Furthermore, organisms found in the area of observation must further described anatomically and identified to assemble and arrived to an accurate conclusion regarding their physical adaptation and the effect of these environmental condition to them.
LITERATURES CITED Hariri, M., Suhail A., et al. 2001. Description of Morphological Variation in Three Species of the Genus Oxya (Serville). Online Journal of Biological Sciences.