SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4c424fa0c4bf82fb2c153c893fcecd5169dada31e1ef51af0f2bffb8f473dcf5' 
  AND token = '6yQwUHhUmnZKp0umKEVCnwLQkYmRTMPZ4P9s5EUGPVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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