SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0ae2c211af1722a64288d5ade77fd3b3ca213294838283acbcaa29b976de4b46' 
  AND token = 'n+mLACVyCwRPB+YeyFDDqOuPLY+HBQz+Z0Fqh36CCsQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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