SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '560bbe9a9be959df7c2a4835b6fde1f11aaaf9bc1697c62aeb748e8cb8dec907' 
  AND token = 'MQZLeeJ4w3dXbxVrSJulQit4JIQsV0MrLILUYfA5A0s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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