SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47cd5cbf5674a1a0f8ce4bc85368ddd6acdce42daf01e06cb72cf5782e4d045e' 
  AND token = 'qUBWSdzL1iOfrYAfdyWo3EEpZKvwsEeJROdsnWyysz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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