SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0bc519134adccd72e450f5f8107b8e1041fb75e9eb086faede48a60c4439284c' 
  AND token = '0jMSYMqeNDL3AgHRXWCaBTCT3iVSEke9kijPhSlNbqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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