SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d073d2e37143f79baa3d798651f6a192bde17c7496a6152c0b77760b91f29cf' 
  AND token = 'NBNIAQKFORk0DrHseYvqwc7HagKoFv6DwGVCmUAd0OM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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