SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e001df310ee331e75f64caad7bcf9627d49fd3bc26d68fe0a6055cd1968c32be' 
  AND token = 'eSUJs3WMz6LsL6GUe8DfyM7mb8R64svwcafNdzYgm2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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