SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bcad48ecc3541d525ba7d77d69a3ea3524b021fb689b4c7f03f4684bc82f351' 
  AND token = 'N5ctvawFLWAVeD7gwvDaEOvpexPmmGmU6zBDNtwKt/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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