SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ab2572a4b366a6d645390b924067b01fbc8c7aba31b67353c3fe5eacc6251acf' 
  AND token = '3KleOKpNDt97Ld5Qm/2bPgRKT19idAlgN680lFdn9zU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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