SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '438d85df64b228b045a4ca79e6e299d4cb913c342ee87ccad209041545e3b358' 
  AND token = 'QPo8YBxsZhUarKNMaP9193TbuQII7GDKhugJkQGLGCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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