SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6f54d436c7d0c86be173353d9e2e35afde1dfe57b5524294c21a521de410f33a' 
  AND token = 'A4rIAbFJFjSx4fsMvmVi7VWivODJOmv7scA3bTTjCYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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