SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd33f5a7b12fdff11de1acde277537c085f9fede8d97eb0de0515fa6b10cf903' 
  AND token = 'L4//N463eRG/I/lXYxBVDdMXR59TM157Z/Zu4+ofXMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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