SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '664bfba4085ffb62ce0b10000748f13e243373babca142c0aba12f6cac63e232' 
  AND token = 'avEG8q5x34Ui/WcQdI+LmkI1DsadLjJg4WGb0Dfm314=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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