SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd7c998fe76c10bf320c34030a64c1b9efac002dac3736ece6084c8a7a612097' 
  AND token = 'kUMoT+4fsQCIYxlZhv5/xiC2pIilsi+rQ4DtKOrAj+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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