SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd295ae1c9678b7e6966e4adf4657fefa1b204f1fd64f5e37f0eaaed0e5062131' 
  AND token = 'pCCtL5ji86NNmxLwp8tluMYPi/7NDzOX7rAgsf13rCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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