SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a313ac59994921bdde1c2d9f0aa7c1cda47a9ba5c10ea25feb480d915d7e9f8e' 
  AND token = 'raWNyvontuTR9EY7wIhOB1OvkH6YzA/VstAqpetZud8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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