SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8e7190041157074bcc2261cd96c70f2dd7a976b2ea37f7fdf713b90c4616c89' 
  AND token = 'q1ZItJfLBgj9xIVvOnV/XV5QAsSFFYNR9mv5l7T/YtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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