SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3df0b07e162c8b4ec93ac9495ef5932c0e68eb3308fb30000d6d8ebc817c4736' 
  AND token = 'ASir0q6mA0dI42rS78jfbGtyy8A5GLRPxS+kYC9sOhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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