SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8efe61dde642240a08044a7793fa12b209ddc156b6334d514565ef47adcfca09' 
  AND token = 'rQxy5AWZkuo4/NGlVStkjJLf0Ed6NfI1Dx46yVZAxYg=' 
  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"
    }
  }
}