SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6321d9fceb79295d86af8bdf69b8182badba40010d1ebff53c44c1e1b3285590' 
  AND token = 'W3//dXwmb+I5+0zdDiQp8kYLT+STx9Ww4RZkWK3Vm8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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