SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6786144a79fed55df33086ef654aa4cd06f9c265ce03d7488cd6fcb7546031f4' 
  AND token = 'wCE22g6cv+WLWlnqMFHoUvU+/XvL2na9NcSGPooTfFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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