This PBS wiki page features Crocus species P-Z that bloom in the fall.
Crocus pallasii photos by Mark McDonough. This autumn blooming crocus is perhaps my favorite of the fall blooming crocus, yet it is rarely encountered. The species is from Turkey, flowering late in the season, being particularly weather-resistant, among the few crocus that are able to keep flowers open on dull overcast days, and it is among the most strongly perfumed. Many silvery lilac flowers open into a bunch, each flower with a deep purple eye and bright yellow and orange promiscuous parts. Typically this is the last crocus to show flowers each autumn, withstanding considerable frosts. Here it is November 13, 2005, and it is still sending up fresh flowers.
Crocus pulchellus This autumn-flowering species is widely distributed in the Balkans and northwestern Turkey. It is a good garden plant in temperate regions, fairly winter-hardy on the North American west coast. Lavender is the usual color, but white forms are common too. It flowers before the leaves emerge. This first photo from Jane McGary? shows the cultivar 'Inspiration' with two deformed flowers, possibly the result of virus, but possibly due to physical injury. The second and third photos were taken by Mary Sue Ittner.
Crocus robertianus is native to central and northern Greece. Brian Mathew believes it is most closely related to spring-flowering C. sieberi, although C. robertianus blooms in late autumn. This is a good-sized, substantial crocus, shown here growing in a bulb frame where it receives some summer watering, flowering in early November. These specimens were grown from seed purchased from Jim and Jenny Archibald. Photo by Jane McGary
Crocus sativus is the source of the mysterious spice saffron which is created from the red style. It is lilac-purple with darker purple veins and no yellow in the throat. It is sterile and only increases by corms; it is not found in the wild and may have been a variant of Crocus cartwrightianus. This species has been a source of frustration for many gardeners because it rarely blooms. Deep planting (12-18 cm.) in well drained rich soil is helpful to stimulate blooming. Photo by Arnold Trachtenberg. This plant was thoroughly discussed by the PBS list in 
October 2005 under the subject Saffron.
Two photos by Mark McDonough highlighting aspects of the plant growing in the garden, a face-on view and a profile view showing the long deep purple tube. Only some of the corms produce flowers, so I would agree that it is shy blooming.
Crocus serotinus ssp. clusii from Portugal flowers with its leaves. It has finely netted corm tunics. Photos by Mary Sue Ittner
Crocus serotinus 'Poseidon' This named variety has deep colored purple blooms on very short stalks, and also rather fragrant. It flowers later than most other autumn crocus.
Crocus speciosus is an autumn blooming species that is native to Turkey, the Caucasus and Iran where it grows in woods and open hillsides. Flowers appear before the leaves and are lilac-purple to deep blue-purple to white with orange styles and yellow anthers. - Photo by Arnold Trachtenberg.
Here are two more photos taken by Mark McDonough on October 21, 2005, showing aspects of the plant growing in the garden. The flowers are relatively huge and showy, making a great show if not beaten down by rain.
On overcast days the flowers remain closed, as shown in this photo by Mark Wilcox, taken in October 2006.
Crocus speciosus 'Artabir' photo by Jane McGary. One of perhaps ten cultivated named clones of C. speciosus, the most widely adapted fall-flowering species for North America. The surrounding magnolia leaves show the large size of the flowers; most cultivars have been selected for large size as well as good color.
Crocus speciosus xantholaimos two photos by Mark McDonough taken on October 21. 2005, showing this fine variant with boldly veined flowers. It seems more prolific than typical C. speciosus, with a long succession of blooms.
Crocus spp. autumn, photographed by Tony Goode including Crocus niveus (tall white left), Crocus tournefortii (lilac front left) Crocus goulimyi (lilac top right), Crocus goulimyi 'Mani White' (white top right) growing in a raised bed in Norwich UK
Crocus spp. autumn, photographed by Tony Goode including left to right Crocus serotinus ssp salzmannii (lilac), Crocus pulchellus white form, Crocus niveus , Crocus hadriaticus
Crocus thomasii is endemic to Apulia and part of Dalmatia. It is an autumn blooming species, with pale to deep lilac honey scented flowers.
Photos taken in habitat by Angelo Porcelli.
These are cultivated plants, which grow larger and more floriferous than wild ones. A good degree of variability is present; some individuals are quite dark, others rather pale, although never white. Photos by Angelo Porcelli.
Crocus tournefortii from southern Greece and the Greek Islands is a species that is unusual in that the flowers remain open at night and in bad weather; thus, it is best grown under glass in less mild climates, although it is cold-hardy to at least 25 degrees F. It flowers after the leaves have emerged. The first photo was taken by Jane McGary. Two additional photos by Mark McDonough showing aspects of this, perhaps the most beautiful, of all autumn crocus. I can attest that it is much hardier than Jane indicates, as mine are planted outdoors and never fail to bloom October - November each year, easily surviving winter temperatures well below 0° F. The flowers too, are weather resilient, surviving freezing temperatures in the mid 20s Fahrenheit. The exquisite flowers are lightly fragrant.
Crocus wattiorum is a recently described species from southwestern Turkey, belonging to the series Biflori. It has large, vivid blue-lavender flowers, black anthers, and deep orange-red style and stigma. It has been found in only a few sites, one of which is illustrated in these photos taken by Jane McGary in early November 2006. The crocuses grow in humus-filled crevices among tumbled limestone boulders on steep slopes covered with primarily coniferous trees, receiving sun part of the day. It is a wonderful place.
General information about this genus and about species that bloom at other times of the year is found in the PBS wiki Crocus page
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