SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01d2c5145e6d6d314c7e5b397c84f8d0bbc5c9837a78496a72ba85ec9194442c' 
  AND token = 'km17ovZdwte6fV1z/q3CfnoayLbV+thORAsErGvY2B4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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