SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af69484aab9b4526329cd46a29791ab43f28d602e7f15cc2ce96897d11a414fa' 
  AND token = 'UtEO6qgisJZ8j4ZKMld/LNfqq5XjN+8wf0QoVeFChYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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