SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67b9079758c376e39ea258b96a77088f2dcf1de82b5e74fa43a507f768a257bf' 
  AND token = 'HOKFJ1hj3bUfPdbJdJdBjls9Yafe16NDCYg9DKDxCLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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