SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ba81b070a711558ac1308b93ca209b09a68603ac67784b9c574e85468176932' 
  AND token = 'EK4Vv/GqqNeDCQ/baHCJQEnGtc8Nc7Z9ba5LUADlK64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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