SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f41ea0a540aa309ff229b7f16601b3452d9dec1c013ef9f22c9832634621d8f1' 
  AND token = '0atLh7phMLcmweGhwnB6fCN7Pgm7mr/sOq4GGhzZTio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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