SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a85cad9fa4b61fd270fa7b2f557f44d9ae0bbf78f53fb94b1eec05a100c946e4' 
  AND token = 'lisuTqtH5ztta87cxO5N7aS+M6fLVQWscdlNrMJDHIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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