SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6855321955fd5b10d89ea9d03f0da20fccdec5e8e9dccba6877e45d01db7b007' 
  AND token = 'X3HIxcEaqo3HSUoQTTro3P+/NHXh/xqQllneaMuWOlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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