SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd9762ad183e24c3f39b37d3609d33c8e85646da8646b6c10c23b4a30515343fe' 
  AND token = '1CG4Fyul8JUSShYWXO+NKyR848ibEPB8e32ghCkiW0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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