SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a5472a13ccb30f235990312e3b5afd09c54c76b06ac7f5cf52389e19257a11e' 
  AND token = '4ets3KBNNph7eQ9FtBGSrBNSpAGvfkNjtm9jUldwkfw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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