SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2fa5ebefe31f044eb25fa029e503139df8b2b7f73c2a7e92afc55db5d8df0beb' 
  AND token = 'mjFXx+C8+JtGxLzQRFkT5aBlFl4W+JMb/gRRGCEwtmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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