SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73280109aae3f6ad8b268429bdaac6345cbd0b575732ba136c52d3029f71f770' 
  AND token = '5IRHVa+l5/R/vlcVSPKdYxmt6GDpIBEz3sggkJLjfiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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