SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da565ad35c2814002ce60cf94344c70ccf17b1727cf8f93165eb1178433e6c99' 
  AND token = 'iuPUFpuO0ckmhG+8vg7iehVCt7XoPEn2bvWoXj2iqro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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