SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '187573f7322f565d84ddb88cfdda81056077c95865860a830a3f1b012cd3930d' 
  AND token = '/Up4QxND+7LYD5+dqSsYqqjt9H6XBqy5XEqWFovOlrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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