SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '469cbc35716f32d684ce89604803607822bb214a64b104e4659d3c61a7990d18' 
  AND token = '7aaOIofgCk8FysB1sQJkElXfahWHzk0f9lJYF1iCISY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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