SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a00d1764320505c0686b69f650e225cebcd979a59a0d19b87bce0b418adda2e7' 
  AND token = 'uR3ktYQ0bNWTbRftqOKfIsVX3xrApE2qULFZ6brQxyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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