SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '103445972070e9a06a5ac07128057a458208e0f9de8ba4ee170ded6201075525' 
  AND token = 'Cy6hG/+q3tzD85x9fBwGRwzs0Fpk0YeqZ2k4hYao7I4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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