SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cba68b8534621995785a56442abcc97a3edb54d6f6b8ca9364e00fc71f0dd059' 
  AND token = 'fFQOlzr43ISqv+PDVJN6qNrSV9FSlYn1oATJ8pjxrhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00083

JSON explain

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