SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f620233bd45fce359ab74bbc543015b0b2a30538653d72a280aa75f926a7a577' 
  AND token = 'B0xBOF5njKjlwP18rGjiHgRM7J9YizOcVPYs3BmcsCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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