SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c365567cfcaf74f46a9d9e53a5bf5f1192f614a27a38824b639a5d0a71123db' 
  AND token = 'M9jqIFgoB/CC1vkML+qBB0DH47bpmj1fKuaQvxPVAlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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