SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dae25cd3eaa5a360c557e94a936fc6aa7de465f369398780cf1e24dbd143cd8c' 
  AND token = 'avAnVp+rtC33iOCCTRn1/ephCUHBcEhTfalEHkItLrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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