SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '53e4d6ab291f8fea44c1bb79d4d18752c6ee853d7f1ffd01bcb7067aeb830e13' 
  AND token = 'UIVjxjxY5ehjXaGqoQ6BYuDoeWtvCJqfVLSwPaf6lNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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