SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9ce6ff08dbefc894f987479b03004844ba534d93c50d8a0a968b9e7a2fe2115' 
  AND token = 'OdJc1nPrSTMaPZj6gSlUDDFGy2pehZp1FOSvnc6QIOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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