SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e09d966add6949239003333172aceb4bd76e16990a97a0b61b2503f2011127e' 
  AND token = 'tXFHdt8CzOeVIvSel+WmVi9GmgRIYUr83kcM8U2Hfck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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