SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b484c925805263bb6f37e26ddc731ec55ed0545708f53535a32d6f2c4fb4bee1' 
  AND token = 'XvIKpu/TpgMS6kro4g6LL0A0nISG8hNeaFm+YTjRMGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}