SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9d3e37a6db18bc4ede55e96a69542d0fda9540aca641d9168d7d7c47aa6add9' 
  AND token = 'bRg6BpySvAno7xsqXmRv53ZSgE6umLkYyENYrawZvjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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