SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '452dbcc2e2bf31bab5fe78fdb07f359d75dddfe688b25ffc69fe00972538b1b3' 
  AND token = 'Bh0JjfdIRZ5VGkrIgMOH26jOCovRr6y7EcolIQMKw3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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