SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7feaa659c6aa5f49aff7605ca1b0ee7c41e6e4058243bc07503b35ddd8a15e9' 
  AND token = '7unYy2txhlK4CP+2MzvOIEdXJCDOuj+Y/KESNhDKw8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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