SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '169240661e1154b9630c4b15dd365ee04981f482325a9cd90c71c83b94a19696' 
  AND token = 'jKXR+DBsQLkAxo2SP6cPAqCNdYqJ9y4yKzqQhVsL1qQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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