SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '863ff0e1b34f7e6dd08621773a403ecad8ed9985c65b6786df08062d446b77df' 
  AND token = 'pgCAdZvUXtABOWKn72+iwLuoYBbSqnytZWi/npzIorw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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