SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48bd732fd1ca4b9cbdb8b2099e48b204f602f4c92d5c32bd0043354bb9a2b160' 
  AND token = 'oos0/Dpou4YT0ie78IjULZjxr9MlW5kvd+WvAoYs0WE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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