SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0def98ebc83acfad5c887be8a9888b183dcc7fd4888cda13e0d05f9d6390fef' 
  AND token = 'WAMARz2LHoRbB9OT2onLSTP1fKqYpGRvopPbOpYVaaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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