SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2904e22b37808e5685a733a3d6db22bf5afcd181a55ce5fd58eebd6fdafa0c26' 
  AND token = '1g/faeWU2N1HCMDnlwtYkYTCipedTkzGSBiFQZlWM14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}