SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df0ac1510122768bea7b1de778287f2825368721a90cc348ec619361444b1075' 
  AND token = 'aEYTA/apymSf8ujSD25gx/Z9AbNBCrh6vmzr9TFaSZQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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