SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5c9113c59250af1f2982546680e3d37df9582a3b7d57694a175287306ec226c' 
  AND token = 'q53EhA17MZjG7YgbM/0Vka2hTJG+V5gzRpESld56WDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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