SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f1820e972108c7772f18b934a50ae27987bdb6bba3758077a0acb68656e01a0' 
  AND token = 'IOCFTm35qAvhXeI08PIH5sEHMPtoSlTHy05Ly+Yknqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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