SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bb4fa14b9c06b0d28e40230a42b5ccf1d261591d7b39b1bd248876a0b8b17a8' 
  AND token = 'B5uVEqa0HdLGerlTMw60BfBnuk1rgArDrzaixrS1q8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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