SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a337dd270dd8a2859ffc97c4da18624c4d47326dd299a6697a6eaba97586493' 
  AND token = 'CGuGRm4ap+I7nCfuaLJHMpmw/jYLhJZZDE7S/yh5EeQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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