SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '274e90c8f146807e0ffc46f26eec56c9494ddebf80cc51af88a32dc4d02dce7d' 
  AND token = 'UPbz7UlCTIKeeBog5oSlB6cEVmBpLXGxkigkA7D3Xbw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00057

JSON explain

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