SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ed62ad0a5e0e09a7c0d6f95ba61f143525caee0f1f8bc99a498686307184730' 
  AND token = 'Xa14fzyPRyTquSPPbdmoumMZwV0EEw9oVPh9tyFaLe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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