SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '46f0a2bc17991f75d6b87de3c0b879e9bf991ee79585ca6cf089794a82e9b284' 
  AND token = 'yJudI4l564ywVgP+ey7VavYqBhq1Glxy55QSuMkXOQM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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