SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd7af2ff2b87cd938c7324ee188ee813d7cd54a3f20bc4f4a976b88a0be669786' 
  AND token = 'pCiobU5g6jhUOKRLaUFKjOyNKpuzWies/F6ZaJ4+Oks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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