SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '949e7bc2faa8beff343813db13040e5e117716cc0bd4a582356b8dd94bb955a5' 
  AND token = 'BPLIB4Svv6PXqOv9GenEWm/nBlaz7hKp58su6NkzXwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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