SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff7db1e855e42f33ddde6157907275278edcd8e0f89d5040684ef26e22ae0c8f' 
  AND token = '+mDj+CrcomPUS1CuAgx5ixOvSUh69HQSzn+eI/6DBYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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