SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab8ea5eae2fd0aeb2ea70ce3285d19786ee569416e41fcccf60f67800fbc9108' 
  AND token = 'm1cmtYOX3Acnq8ZC3I+ym9UeEBvj9d204de66qfZrO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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