SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d60607a23b2b813d44b0881a80bf32b1ce222d8aa87d9a48e3ac58002af948d' 
  AND token = 'SGmCL7iKKz2VdQG4wfNBgNVKufnWZqhnHre+P/FKLGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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