SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27b25c7fc3b8418959ce0ea02ebe96ae9b8e8b8095a3fb9c61752a4fbf436007' 
  AND token = 'izCLskfazyv/D0Mim6GjBqFyrwV9tVqVJrKnCBR70Fk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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