SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811102bcf54f89300a647c9baa9ab4e5ac0a81d03b4b434e9889e41da21c6fee' 
  AND token = 'TsVSVPZxsoQOSrs0+DlQblwjDo2mUlQU7cvjs/hl4Ts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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