SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99d3bb0b9a3f3843e92a904cf71c7d95e9fb8602ab4b79a65031ccae12b0ab5e' 
  AND token = 'o/v/ejr7Zx3Pb5uSsVqRKW+doFRkIE1mEXif+sEn88c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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