SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b003df41067250979d2c47faa7eb739284ea5c1f3d5ea81d912bcae0bdd689fd' 
  AND token = 'NXuy0RTyza8PrbwyEFE5uV7WBKLDfWPzP0i32LFlGeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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