SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b3554548815fd651821c6d9cad80a10fa26796fc5c2b00a66a8a25fad2b8763a' 
  AND token = 'hqdRjJETJPVS6PnbnPGsKmPmfwZ8xgY6lpCQ57IKlfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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