SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4a41c70fb214cfdffd0440b6393e250bc4c885b307b69b967f0ea4e31f40b2d' 
  AND token = 'aVN1wxMa9Jhzzy8fQjm1Rb8X7YQkyXJajc87ZzKQN24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}