SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e469a010c8ff3d9a4da981c61d65d1fcaceb6d00d5894a1e51aee359ff8a99b3' 
  AND token = 'pXcdTk4LOR0JkijjT9R7RZqscCRV3A1i6CIuUVB2OKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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