SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'db98062e58e93d2910b405fdef9dfff895f0b6198838c58acadaade382c3bb09' 
  AND token = 'BG0lrYBgx4948PYdEUKA4Da3H0ygS4gYxITTnrxk4Wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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