SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc1eeb4aa1817d46b63b1c72b29ab11f44876ab428ee6a01de0af3c7ec2785ca' 
  AND token = 'BxjxHIVNrpII8FWrlFm4yB4JJgGnFXL4mKrsSgusydM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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