SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0948a038ee673f0861e8dd22c3b44c87ceecc2fae55ca1159023a901a9e7230' 
  AND token = 'YFePpoTDpBzqkr9Z5klthHRDqfGPrfX5dpd98qIx98k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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