This alien, which bore bluish skin and facial bone plates, was among the residents of Deep Space 9 at the beginning of its Bajoran administration. She visited Quark's when it reopened after Commander Sisko and Quark made an agreement.
When the station was under attack by the Cardassians, she was running across the Promenade with dozens of other residents in order to find safe shelter. (DS9: "Emissary")
This alien was played by regular background actress Tyana Parr, who received no on-screen credit for her appearance. According to Parr this alien was titled "elegant alien".
This species was originally conceived by Michael Westmore, who described it simply as a "humanoid" on his concept art (see left). Westmore's ideas for this design were for it to have, "Skin over skin," "top skin smooth," "2nd skin textured," and "light eyes." (The Making of Star Trek: Deep Space Nine, p. 14)
More members of this species were present on the Promenade shortly before Federation forces retook Deep Space 9. (DS9: "Favor the Bold")
A female member of this species visited Deep Space 9 in 2375. She was talking to residents in front of Quark's and later joined others and had a drink at the bar where she was among the patrons Elim Garak shouted at because of his claustrophobia. (DS9: "Afterimage")
This alien, with tendrils protruding the top of his head with a bony jaw and brow line and facial spines, visited Deep Space 9 in 2374.
During his visit he passed Doctor Bashir on the Promenade shortly after he submitted his proposal to surrender to the Dominion.
Later, he was sitting at the bar in Quark's when Bashir yelled at Quark.
He was then playing dabo along with Bashir at Quark's shortly before the genetically enhanced Humans boarded a transport departing Deep Space 9. (DS9: "Statistical Probabilities")
This "Westmore alien" was played by regular background actor Bill Blair who received no credit for this appearance. A headshot of Blair made up as this alien can be found on his website.
Alien with head tentacles
This alien had tentacle-like appendages on its forehead, and on the back of its head. Another tentacle was placed right under the mouth. The forehead had several ridges and no ears were visible.
A member of this species was on DS9 shortly after Miles O'Brien's correction period with the Agrathi. He passed Keiko and Bashir shortly after O'Brien was returned to the station. He was in Quark's when O'Brien and Worf were playing darts and later when O'Brien ordered a synthale and threatened Quark. (DS9: "Hard Time")
One member of this species watched a Dominion convoy passing the station through the wormhole from one of the large windows on the Promenade. (DS9: "Call to Arms")
A member of this species was among the many civilians and Bajorans on the Promenade when the Federation gained back control over Deep Space 9 in 2374. (DS9: "Sacrifice of Angels")
One member of this species visited Quark's bar in 2374 while Quark, in disguise as "Lumba", shared a drink with Nilva. (DS9: "Profit and Lace")
A member of this species visited Quark's in 2375 while Sarina Douglas was aboard the station. It was talking to other guests of the bar and sitting on the bar next to Morn. Later it was passing Bashir and Miles O'Brien at the Replimat. (DS9: "Chrysalis")
A headshot of Blair make up as this alien can be found here as well as on his website.
This individual visited the station in mid-2371. He was present on the upper level of the Promenade talking with another individual when Julian Bashir and Jadzia Dax walked past him while discussing Bashir's Carrington Award nomination. When the individual finished his conversation, he took the crossover bridge to the other side of the upper level.
Later, he was walking on the lower level of the Promenade, passing Quark's around the time Grand NagusZek decided to buy the entire bar a round of drinks.
This alien, who was better seen in Quark's vision, was played by an unknown actor.
Alien with no neck and heavy folds over eyes
This alien, with no apparent neck and heavy folds over its eyes, was among the residents of Deep Space 9 shortly after the Cardassians withdrew from the station. It was dressed completely in blue and wore a hood. (DS9: "Emissary")
This alien was played by extra Robert Jodlowski, who received no credit for his appearance.
This species was originally conceived by Michael Westmore, who described it simply as an "alien" on his concept art (see left). Westmore's ideas for this design were for it to have, "No neck", "Mouth allows speaking", "Heavy folds cover his eyes", "Skin cragy [sic]", "Back of costume built out bend forward." (The Making of Star Trek: Deep Space Nine, p. 15)
Alien with rippled skin
Waiting tables in Quark's
Talking on the Promenade
This alien, who had rippled skin on head and no visible ears, was a waiter in Quark's. He was later seen on the Promenade. (DS9: "By Inferno's Light")
This individual, who had a vertical ridge along his head and neck with two holes in the ridge around his forehead, visited Quark's in 2374 and witnessed Molly's attack on Madrat. (DS9: "Time's Orphan")
This female – of a species characterized by a series of widely-spaced horizontal nose-ridges, a deep vertical furrow on the bridge of her nose and small indentations on the forehead – worked as a dabo girl at Quark's. One was working on the dabo table when several Cardassians from the Prakesh played dabo, (DS9: "Emissary") and a short time later when Ibudan played the game. (DS9: "A Man Alone")
In order to "persuade" Fallit Kot not to kill him, Quark sent two dabo girls, one of them a member of this species, to his table for him to enjoy himself. The girls were to teach him how to play dabo and Quark told Kot to be sure to ask them about their "double down" betting strategy. (DS9: "Melora")
After this appearance, dabo girls of this species were not seen again.
Alien with upturned nose
An alien with a huge snail-like skull, deep set eyes and a large pig-like nose was a resident of Deep Space 9 at the beginning of its Bajoran administration. This alien took part in a Ferengi game in Quark's and played against a Bajoran officer while Broik headed the game. (DS9: "A Man Alone")
Another member of this species left Quark's while Quark and Broik were waiting for Major Kira at the bar. Later, he stood in the second level of Quark's, watching the ground level, when Kira and Odo approached Quark and his holo-imager. (DS9: "Meridian")
A member of this species joined a drink in Quark's after the strike of the employees. He stood near the door. (DS9: "Bar Association")
When Keiko O'Brien and her daughter Molly returned to Deep Space 9 after a lengthy stay on Bajor, a member of this race was traveling on the same transport. (DS9: "Accession")
A member of this species was shopping on the Promenade in 2372, when Onaya arrived on the station. (DS9: "The Muse")
All appearances of this species were played by unknown performers. They only appeared in the first four seasons of Deep Space Nine
The Star Trek - Master Series I trading cards by SkyBox International referred to these aliens by the name "Batwing" (card #80), and lists them as appearing in Star Trek IV: The Voyage Home rather than Deep Space Nine with a quote from the artist, Miro, reading, "I nicknamed this creature 'Batwing' because of his ears. His mysterious alien face made him an interesting figure to capture on canvas." StarTrek.com also refers to the creature as 'Batwing'. 
This dabo player accidentally dropped his beverage while in Quark's in 2369, and Nog replaced it for him, free of charge. Quark criticized Nog's generosity the next day, saying he had warned Nog about acquiring Rom's bad habits. Nog assured him it wouldn't happen again. (DS9: "Progress")
This dabo player was only mentioned in dialogue.
This alien was a customer of Quark's in 2369. Its head and face featured long hair while the skin seemed to be grey/green.
It joined a Bajoran woman when visiting the establishment. (DS9: "Dax")
He was later among the panicked crowd of non-Bajorans at the airlock attempting to evacuate DS9 during the Bajoran coup d'état in early 2370. After Commander Sisko told the crowd, containing a high number of Bajorans, that it was best to get the children and families and non-Bajorans off the station, this individual was seen gaining access to the runabout. (DS9: "The Siege")
He exited the turbolift, cautiously carrying a gold-colored box, with two Starfleet security officers escorting him through the Promenade. He later walked among the crowd of Skrreeanrefugees as they began filling the Promenade. (DS9: "Sanctuary")
He was talking to a vendor at the Promenade near the Replimat when Tiron approached Major Kira and Odo. Later, he was standing outside of Quark's at the bar and was having a drink when Tiron told Quark about his "special holo-program". (DS9: "Meridian")
This alien species, identified on the "Second Sight" call sheet as "Beakface", was only seen in the first three seasons of Star Trek: Deep Space Nine. Over that time, the make-up was modified slightly. The alien seen in "Q-Less" had white hair and a light green, mottled make-up. The one seen in "The Forsaken" had green hair and his face was nearly completely green. Beginning with "The Siege", the appearance always had dark multicolored hair and a dark green complexion.
A bidder at Vash's auction in 2369 (DS9: "Q-Less")
This male alien with grey skin, who wore a tight black and grey suit and featured a prominent forehead, visited Deep Space 9 in 2369 and was seen on the Promenade before he joined a woman at Quark's Bar. (DS9: "Dax")
An second man, wearing a beard, visited Deep Space 9's Promenade in 2369 where it was chatting with a Human female at Quark's Bar while Jake Sisko and Nog bought jumja sticks. (DS9: "The Nagus")
Grey-skinned alien with large nostrils
This resident was among the people who were evacuated when the Cardassians, under the command of Gul Jasad, attacked the station in 2369. Following several explosions on the Promenade he was hit by debris thrown through the air. (DS9: "Emissary")
A race of aliens with pink, bumpy, reptilian skin and clawed hands. Members of this race were often seen on Deep Space 9's Promenade or in Quark's.
In 2373, two members of this race were customers of Quark's. Arissa alerted Quark that the two aliens were actually cheating at the dabo table. One member of this race was standing on the upper level of the bar and pointing a ring with a hidden graviton emitter at the Dabo table where his accomplice was winning one game after another. (DS9: "A Simple Investigation")
These individuals were described in the script notes simply as "Alien".
A member of this race was also present on the Promenade when Odo finally admitted his love to Kira Nerys and the two kissed on the Promenade and when Grand Nagus Zek visited Quark's Bar to name his successor Rom. (DS9: "His Way", "The Dogs of War")
A female member of this species was played by regular background actress Ivy Borg, who received no credit for her appearances.
Both performers received no credit for their appearance.
It was not entirely clear if this was a unique species or means of attire. The script vaguely mentions the "Celestine" in the performers section of the script, while later in the script, as well as on the call sheet, they were simply listing as "hooded aliens".
These individuals were characterized by a large trunk-like appendage emanating from the back of their head and many horizontal folds across their whole face. Some members of this species were characterized by a dark stripe running down their face vertically. These aliens were often seen walking along Deep Space 9's Promenade or as patrons in Quark's.
Two members of this species visited Deep Space 9 shortly after the discovery of the Bajoran wormhole in 2369, where they visited Quark's and walked along the Promenade. (DS9: "Emissary")
One member of this species visited the Promenade and Quark's Bar while Grand Nagus Zek retired from his position and named Quark as the new Grand Nagus. (DS9: "The Nagus")
In 2369 Nog, in the company of Jake Sisko, was throwing small stones down onto two members of the tailhead species from the second level of the Promenade. (DS9: "The Storyteller")
A member of this species had a conversation with a Markalian, the two were laughing while having a drink in Quark's. (DS9: "The Homecoming")
A female was in Quark's celebrated a bit of good news with several of the station's Bajoran personnel, while Quark, Rom, and Nog, discussed Nog's interest in attending Starfleet Academy. (DS9: "Heart of Stone")
These aliens were nicknamed "tailheads" by Michael Westmore. A still image of two members of this species can be seen in the DS9 Season 1 DVD special feature "Deep Space Nine: A Bold Beginning" and Westmore discussed the make-up of these aliens in the special feature "Michael Westmore's Aliens: Season One". Vincent Niebla worked on sculpting the head. Their make-up was changed slightly between DS9's seasons 2 and 3 and the black vertical stripe was added.
This yellow-skinned female – of a semi-reptilian species with large eye sockets, large slit-shaped nostrils, and a bald, elongated skull – was an employee of Quark's who worked as one of his dabo girls beginning around 2369. She usually wore outfits that exposed the bottom of her breasts, as well as small jewels that were encrusted along the back of her head. (DS9: "Emissary")
She was also working in Quark's when Constable Odo attacked Ibudan and later running the dabo wheel for several other players. (DS9: "A Man Alone")
She later operated a dabo wheel and served drinks to the auction bidders at Quark's first auction for Gamma Quadrantartifacts. When Q created a boxing fight between himself and Commander Sisko, she was one of the bystanders. (DS9: "Q-Less")