SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dda1ec31d4d3aebdd9efc135c85a1ccf5fb25d9f976a832a3ef90e817080bb74' 
  AND token = 'BRY2qOzglIvdbjuTPZRFOSL110l4hZnt5nKrQXvc+iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}