SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '81b43a32620ed4dd8a5112a1c0ac5958c54354e9456311ca8e726cbb6d8f0eb2' 
  AND token = 'Ge/B6afI/gzVMPtBxAjXjWJ+lzaYy89Hb7NF3s4m5cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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