SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00f1231cbbf90de0edf2ac7180ff64e5b2652de78aa5661123205245f2fca308' 
  AND token = 'uNQhNXOZyfQaCmEosDvXcMfnt3JAtVJuIdxNVKak2xw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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