SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9455a7610cb6b49782deb6a7f6ffd05d11dd9dfcf8ce62005567a968a313d053' 
  AND token = '+6CuzWX0HK+/iqxxOUHMGQipZozFxANQ1A3oYPfXPfw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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