SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ae6295d1bfd7f6cdeb25b42aed75666636de8396f757be6d956c7970397d3edd' 
  AND token = 'GUs6bGEHk2s5bhryRZd5JmuXoV2PeJjCuekuHTul0Yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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