SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4118565bbaf89ed03366c882c210bc07d13ea4308ce0c0233bfa690e7c394935' 
  AND token = 'LtHNkB+n2YeRuPtMzWMCz+sFv46phKMMTZNqKujuON0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}