SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f45d69a4f891081adb02cb9090a86fc0f1bc68c92a53f825fe978aa603ca13f' 
  AND token = 'jdG/LwluH69wRVtglnw9CnpdDfFZ0ofJCTX21t5d9Mc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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