SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '303d413ee751151eb24df48d1d605b099bcf7a66b0c5cf1263c78c2fe4b1c783' 
  AND token = '8PwHOaq2UNt4kJgN2+6n2hY5hsN7zmKPDV8h2eHRvBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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