SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '772ffca8ce7574694f5725da12d91fc77faa4a64cf0fb5f3dd293900a9638f07' 
  AND token = 'QfBw3a6Mt8LuXsTcl2K750kdV41a+kwoBxfxPuQNCKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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