SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '006a42fcf85b3664d811bfdfee17adc8571877d3cb1d9fd51cd9c39898675428' 
  AND token = 'ijTQOtUkF77zgZ7Li3dJsg3fi1bQXeJnqdrugqSbdfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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