SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72ca343b885d1310270b2a06c5f62c76eb07289c7fb3c22cdddad06f26e3f5dc' 
  AND token = 'EUDyeLdhuRJlNeL8+cPTYT55ryxTmRHsJCpdIG51X38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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