SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a4cf45d8ca2a6743e460aaebbb82a3f10ae70b7cf0ddb52c4872bc7562ca572' 
  AND token = 'Yk5KtfafXv3tDgT5/Fg4+VJKF6Ir6BpVp+6n4hnIpmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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