SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '32c0acd61335ecea770033695adb3afa333f5bc6e319edf3796492a0ab87eac4' 
  AND token = '5Gf+gNnSgSMbYvRZGTPejbfUGry5rYBUITwMr9JL7N8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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