SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aa0395d2bbc86d455195e598205886b2e592b5c98c6dc2ce07072cc08fcac0c' 
  AND token = '2SU5PKGJbhoOP4dU3dc7QQnaDPyXannpDy+nHZUj6as=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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