SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6997c27ef5c5fa1f509b1464d6801771a5875df78176517a4c495c70ec932c77' 
  AND token = 'Z4yKnw5rvBXXrJj6QEwGPTaT83obW3HUkaicJF3UyKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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