SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85583170b57a37d143bd02c17d784c8d6f83ac81726d0822987545363468b4fa' 
  AND token = '/PNNlDD5YU+/dqFgunbnfGdvxpMZKDLpg/vLoD0w1V4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}