SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5162d4de09848dd30b45a0d54829dcb50abbb127385b6c64ed03572ad783fcc4' 
  AND token = 'G8YrJuy8/7PO+mKJgLHV94uta+vCxopcpwBjr/Zt9Ks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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