Definition Scolopendromorpha is an order of centipedes within the class Chilopoda, phylum Myriapoda. Commonly known as "tropical centipedes" or "true centipedes," members of this order are characterized by their robust bodies, relatively large size, and distinctive segment counts.
Overview Scolopendromorpha comprises a group of predatory, venomous arthropods found globally, with the greatest diversity in tropical and subtropical regions. They are active hunters, primarily nocturnal, preying on a variety of invertebrates and sometimes small vertebrates. The order includes some of the largest and most well-known centipedes, such as those belonging to the genus Scolopendra. Their ecological role often involves controlling insect populations, though their venomous bites can be medically significant to humans, causing pain and localized reactions.
Etymology/Origin The name "Scolopendromorpha" is derived from Ancient Greek. "Scolopendra" (σκολόπενδρα) refers to a genus of large centipedes within this order, and it was also an ancient Greek name for a type of millipede or centipede. The suffix "-morpha" (μορφή) means "form" or "shape." Thus, Scolopendromorpha literally translates to "Scolopendra-shaped" or "having the form of a Scolopendra." This highlights the genus Scolopendra as a representative and archetypal member of the order.
Characteristics
- Body Plan: Scolopendromorphs typically possess 21 or 23 leg-bearing segments (with 21 or 23 pairs of legs). The body is elongated, flattened dorsally, and generally robust. The last pair of legs (terminal legs) is often modified into thick, spiny, or pincer-like structures, used for defense, prey manipulation, or anchoring.
- Head: The head bears a pair of antennae, which are multi-segmented and serve as primary sensory organs. The mouthparts include mandibles and two pairs of maxillae. A distinguishing feature is the presence of forcipules (also known as toxicognaths or poison claws), which are modified first pair of legs located beneath the head, equipped with venom glands and used to inject venom into prey or for defense.
- Eyes: Ocelli (simple eyes) may be present, often arranged in small clusters, or they may be entirely absent, particularly in subterranean or cave-dwelling species. Vision is generally poor, and they rely more on tactile and chemosensory cues.
- Respiration: Respiration occurs through spiracles, external openings located on the sides of most leg-bearing segments, leading to an internal tracheal system.
- Reproduction: Reproduction is sexual, with males producing spermatophores (sperm packets) that are transferred to females. Fertilization is internal. Females lay eggs, which they often guard until hatching. Some species exhibit parental care, guarding the eggs and newly hatched young. Parthenogenesis has been observed in some species, though it is not widespread.
- Size: They range in size from a few centimeters to over 30 centimeters (e.g., Scolopendra gigantea), making them among the largest centipedes.
- Venom: All scolopendromorphs are venomous. The venom is a complex cocktail of neurotoxins, cytotoxins, enzymes, and other bioactive compounds. While typically not lethal to healthy adult humans, bites can cause severe localized pain, swelling, erythema, numbness, nausea, and in rare cases, systemic effects.
- Families: The order Scolopendromorpha traditionally includes two main families:
- Scolopendridae: Generally larger, with prominent ocelli (simple eyes) and often found above ground. This family contains genera like Scolopendra, Otostigmus, and Ethmostigmus.
- Cryptopidae: Typically smaller, often blind or with reduced ocelli, and frequently found in leaf litter, soil, or under logs. This family includes genera such as Cryptops and Theatops.
Related Topics
- Chilopoda: The class of centipedes to which Scolopendromorpha belongs, distinguished from other myriapods by having one pair of legs per segment.
- Myriapoda: The subphylum of arthropods that includes centipedes, millipedes, pauropods, and symphylans.
- Arthropoda: The phylum of invertebrate animals characterized by an exoskeleton, segmented body, and paired jointed appendages.
- Other Centipede Orders:
- Scutigeromorpha: (e.g., house centipedes) known for their extremely long legs and high speed.
- Lithobiomorpha: (e.g., stone centipedes) common, typically with 15 pairs of legs.
- Geophilomorpha: (e.g., soil centipedes) elongated, worm-like, with many segments and reduced eyes, adapted for burrowing.
- Venomology: The study of venoms and toxins produced by animals, relevant due to the medical significance of scolopendromorph bites.
- Invertebrate Zoology: The broader field covering the study of animals without a backbone, including centipedes.