Whitespotted Guitarfish

The Whitespotted Guitarfish (Rhinobatos punctifer) is a key species inhabiting marine benthopelagic environments, with a depth range spanning from 70 to 150 meters. It is known to reach a maximum length of 89 cm. Predominantly demersal, it is found inshore on the continental shelf up to a depth of 70 meters, where it primarily feeds on small crustaceans and fish.

This species undergoes ovoviviparous (aplacental viviparous) reproduction, wherein embryos initially subsist on yolk, subsequently obtaining additional nutrients from uterine fluid enriched with mucus, fat, or protein through specialized maternal structures. It produces litters of up to seven pups, maturing at an approximate length of 62 cm and measuring about 25 cm at birth.

The Whitespotted Guitarfish can be identified by the following morphological characteristics: a wedge-shaped disc with a width constituting 29-34% of the total length (TL) and a length 1.2-1.3 times the width. The snout is relatively short, with a length 2.2-2.6 times the inter-spiracular distance, and 3.6-3.9 times the interorbital width in males (2.9-3.4 times in females). The orbit diameter is 1.2-1.7 times the spiracle length, and the nostrils are weakly oblique, their length being 1.3-1.9 times the interna nasalis distance. The mouth, narrow in structure, has a width that is 5.4-5.6% of TL in large males (5.8-6.2% in females). The posterior nasal flaps are broad, with two spiracular folds where the outer fold is slightly taller.

Additional distinguishing features include almost parallel ridges of the rostral cartilage, a subtriangular to sickle-shaped anterior cartilage that is relatively blunt, and a discernible prebranchial sensory pore patch extending to the first gill slit. The postscapular sensory canal is typically notched with visible lateral pores, and there are inconspicuous thorn patches on the supraorbit and scapular region. Denticles are primarily located on the anterior portion of the dorsal fins, with the posterior two-thirds remaining bare. The dorsal fins are relatively tall, with the height of the first being 7.6-9.5% of TL. Notably, the pelvic-fin inner margin is shorter than its base, with an interdorsal distance of 2.1-2.7 times the first dorsal-fin base length.

The coloration of the Whitespotted Guitarfish varies widely, with a dorsal side ranging from plain brownish to greenish-brown, sometimes faintly or strongly marked with small white spots or ocelli, or exhibiting a combination of reticulations and ocelli. The posterior half of the dorsal and caudal fins is usually dusky or blackish, while the snout may display a pale or dusky tip without long teardrop-shaped markings.

The natural habitat of this species includes the Western 🌊 Indian Ocean, specifically the Gulf of Aqaba, Gulf of Suez, the 🌊 Red Sea, and regions extending from Muscat (🇴🇲 Oman) to 🇵🇰 Pakistan.