SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aca23b181a4fdc24d1e722a3ba566ca61f88102df79a00a69d7672e09e4fc7d9' 
  AND token = '7HxbCwH6iT1Auc1iC4J43KjhR0RByejtC6u3T+/2ujU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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