SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9613d2e47e019497fd3748c5dde1b5eaf78d791b07dda31e52e6ba31d8adb696' 
  AND token = 'ayJiVVLeAGwbDcMBVBbENA4guzZ3uFQQb3ZzeSnxsLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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