SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c775d7ced9b63b6a0efdccb7eab50016630dbe95ccddeb604d7efb37d79a345' 
  AND token = 'ihRUOkfwJGQizsdwB1cnq2kX2RarhfLgERap6KqWOzk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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