SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28383705bf2bb91fcb44486a0598dd0b6010954ddc118af12df07d09e224c0b4' 
  AND token = 'DVnqvRWjIUbCr2CrKvTUc7UgJshnHbSPDShUC9ROfPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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