SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25d951e910187cbf9cc6e138fde29ebf8b44a42c85feb1d0ffafd0ad90d20f31' 
  AND token = 'NefUCiwc3nHRAOPYylDMj7/pk/jtVkbTH5yCawSJMow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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