SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '295fd60c0ff89e3d5c49f3e16bbff74d96a4cdbdf6e1d02c741b521263e51ce1' 
  AND token = '8iA/fMj0umVmPv8RFhuTdaJXOgWtNraj7GqI+pFVvNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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