SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '588f01a3fd3552d7f575b3ac6facc4f6550ec5e62faff9dd77c6aa54dd84676c' 
  AND token = 'Pd56VcGwzFN4qKdzIqQ+eqg4/c2YFpQAKh0gzJcxpn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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