SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b9ca2c57e13c4d5aeedd97e72dc68bf8d873564bc758ac1b885786fbffef3a6' 
  AND token = 'NR2wlsyrDyC1DWFfHQG0OTO/+SdC6wR4MqDsclgZvhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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