SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efde7bcba4c423c51fa6fdfc193b323026f91e05a67dc68aa2f26ac8950420c1' 
  AND token = 'pVtIQgYTfcm9GKpu7AsoXCG3pDZjrrZr7BhltouUm9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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