SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8aca08806de64effb7385cccbe54522904363505c29dafc26998e69a0a841d7' 
  AND token = 'dcp4Dig8kSvSvvv5i9XORL4EJzv585hoq43zDZMOsvE=' 
  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"
    }
  }
}