SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df679af4612a00fdb6415071a87245bfa0ee48ec94bfd011e54b15e2ff8b6a19' 
  AND token = 'znTdjbx8LM1rbXHahbSSBUfBQzFkM3UlPDKGEcBJl7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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