SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cef70e90824342bc1584f1c0b3dce3dc8cd2554d7075a43e26f4b8ff8471d0f7' 
  AND token = 'rph6EX2PaC88SxwuHG1lb1fMRG+PgFhzPIFBjOYCkks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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