SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ce1254c28000fa068ced48a2cd8dffc7250fff81d6d6bf38e5e574c21ee0cfe' 
  AND token = 'bgsHqN/cFWFqtkTOe0qdvY6yZK5wGRGA0Q0ZY/fRWIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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