SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58fd5575b82ac2aafb1ec92da116db4d788a5215c65c7787d021e202b5949ad1' 
  AND token = 'v1mAaLOoIA47GBJbWf6jbez4T3965MDPUQuiPnjiCvA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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