Convolvulus virgatus Boiss. ?, Diagn. Fl. Or., Nov. 1(7):24. 1846. Boiss., Fl. Or. 4:88.1879, Rech. f., Fl. Iran. 2:11.1963, Sa’ad, l.c. 86. (Fig. 2, B). (Syn: Convolvulus muscatensis Boiss.; Convolvulus virgatus var. subaphyllus Boiss.);
Gulf States, Iran, Oman, Pakistan as per POWO;

Ipomoea for ID : 280111 : AK-2: Again taken at Muscat, Oman.

First picture taken in May, 06 and the other in Feb,07. These are very common here.

… simply guessing: some species of Calystegia

… has a worthy guess.

     My impression is that the plant in question is likely in the genus Convolvulus as the stigma is within the structural type for a Convolvulus and the corolla with a relatively short tube and wide relatively flat limb is much more typical of Convolvulus than a Calystegia , although some overlap of corolla features between Calystegia and Convolvulus does exist…
  The majority of Calystegia species are native to California with relatively few species in the Old World, whereas by comparison there are many species of Convolvulus in the Old World.

  The Convolvulus are known to cross species naturally as compared to Ipomoea which rarely ever crosses the species barrier naturally.
There are some botanists who have proposed that all Convolvulus represent geographic variations of a single species with no absolute division , because inter-grades of Convolvulus species are to be found inhabiting what is proposed to be the geographic limits for a particular species; inter-grades of Convolvulus species blend in with
the ‘different’ neighboring Convolvulus species / sharing features with geographic neighbors of supposedly ‘different’ species…therefor Convolvulus has so many subspecies , subsubspecies , varieties and forma…likely ad infinitum…
Perhaps the wrong time for me to share regarding such a departure from the traditional / accepted lassifications…
The plant is some Convolvulus but more than that I can not offer at this point.

I have an after-thought and that is the closet I can come to an ID on the plant in question at this point is Convolvulus virgatus.

I have an after-thought and that is the plant seems to match Convolvulus virgatus in many aspects.

Convolvulus virgatus Boiss. is correct ID .