SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd1bb53c472b6696da54c1fcc1fd1a83aa1a005cfec1ab809a72ad1f6d5782e0' 
  AND token = '6tZqDesGIDC1SUFp5OzTP0LVFRf7sSCEBQDu3MX84ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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