About Gasteracantha clavigera Giebel, 1863
Gasteracantha clavigera, first described by Giebel in 1863, has a distinct female morphology. Female individuals of this species have two prominent, unusually long spines, each measuring 17–19 mm in length, which is approximately twice the 8 mm width of the abdomen. The tips of these two long spines are curved, covered in hairs, and shaped like clubs. Just below each club-shaped tip, the spine shaft bears a ring of white hairs. Two pairs of much smaller spines are positioned on the front and rear edges of the abdomen. The hardened, shell-like abdomen is yellow or white on its upper surface, marked with dark sigilla. This spider species is distributed exclusively in the Philippines. Dahl (1914 recorded specimens from Manila and Samar, and modern studies and observations confirm the species is found on several different islands across the country. The original specimens Giebel used for his description were labeled as originating from Siam (modern Thailand). However, Giebel himself noticed that the beetles in the same collection were characteristic of Philippine beetle fauna, and expressed doubt that the spider specimens truly came from Thailand. Dahl echoed this doubt, and also noted the existence of two additional specimens labeled only "Ostindien"—an old, broad German term that covered all lands ranging from India to the Philippines and Indonesia.
