SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f28e2ff84221f15417a4a526078ae3964e43f4dad3f51e5a0ac747f8a86eb7ff' 
  AND token = 'rUluDoc+nAJrFIyhnX+OLG4AJuyqK5DqZWLDsSdBmSg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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