SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '016b465add591e6b1eb6e0813a126816ddd20abd10fbde0d8881aa07c969d68d' 
  AND token = 'wrg6curUaJamBGjPVmBhh2cIa6JqChY+AO4QzyLhXFg=' 
  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"
    }
  }
}