SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '207dd7cf06f7cbc8177f40b7756a36a46595488ce77e16c287ac865c7c426acc' 
  AND token = 'KB3fefjm9sqAqzL+q4NcRB6X3jTcO5Oe9TvQpl90NKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}