SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f5ccdc32c04415ee8515d07c4c1f2ab5e2d073d08e3cae02fe9fb4de489f1e9' 
  AND token = 'ljTaNUrquwIu5t+k3F56LmVKnSaHwNDNsFhdpEIppL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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