SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7834cfed884c6270ae43f187d52ec8805baccfeff7a74341e146f8e9685ed953' 
  AND token = 'RC60iQVVQZjHZGVhCZW6GdAazBPMXbJIP6XaEcAz548=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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