SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8328d674e3b4358f5c6564c6ddf0d794fef7ebf8adcc31c4064f19618e4e1585' 
  AND token = 'uS3Dk73qul/WHCvHuWf5jcSTok/vsd5nfTxSmB65NMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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