SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80ff0146e538d1e889bdf8b9f9093155a019d76e67ff48da1984a8ce4c473b18' 
  AND token = 'YgRdWuGnFUmnputSg+14QKkTWgZXW9cwexYMJwYxnBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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