SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f43846a258dee5b88a901c05e370b57acb57c3224e20c785e13abb0a09d1373e' 
  AND token = 'GseAXWFREFcmpjlN/fle/S9HR3imr5r7c4+RVVKwKDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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