SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '81fc221b197674cf65490039efb9bfff2b2d590f679578f7c0993d550d5196fc' 
  AND token = '23iYGNuGuk3o+mP3Wkldu4/QXL/j0Q/bxJhvVDiQjWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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