SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce8dc64ed5bfcf5334230b7da70c42f5e7709f931a0ddb61b0b8e41027090885' 
  AND token = 'q3JoXczMxzUiWNbjvEwoYynOIH0vT2bSaeVwFBYI6uY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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