SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'da60af6a2fbc5358a8d286520595b13674ad79e4500938cd1ec414fc76b73e74' 
  AND token = 'mRWd/SMEAtnJhxFNDPAXPqjacQpLGQZVnJc1j9oZKcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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