SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '187819edcd3c0a71b638488a123233607e99ff33a40e8da037b407d965aa095b' 
  AND token = 'D6ANJeEGgQE0+eIY/2qY/KHpZ4kwEy61vOwKIlRKHMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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