SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a883195383412d8e1dcf29cf567f2a79189190fa83f1f26eab13ebbbcd6594b' 
  AND token = 'rHchV1WOdcp5fGW7d6v/2hAdJf/le/XCi8a/eymKNUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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