SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdaeb48c099e3981bbc5d6a589449372c5b3fb5fbed86eac1d8965f724a46954' 
  AND token = 'ChPOe1+39ZtB3kTspu++Gy2uPMk6w3oc4An2OKQq7oo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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