SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a54ed8144c78f76cb3d31e816f1d6e091d443c3b97291687ed5581dd8ac3b8e1' 
  AND token = 'VmbLnmxZVZCjjAooZ/HptL16VMa4hwnDpRqGjmdGSYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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