SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13c0893cbe57c39ab8b16038adaa8ac7cc3f6f8214eb5dc6c7cd19b1a8e566f3' 
  AND token = 'yi3owchsH2IoUfYRVCrVc3m1F9aDxWi6n9GwTAcbhxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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