SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49e3d5e2749c9b42c80e13efbd2bfa378a090618c14633aaa3c584fa0ed6a0f8' 
  AND token = 'h1e0NrDtXza+TFgBIyDx1RXsi/Uuvr5+SQ4sl5ZJWnM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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