SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87620ec853f13856a8befa7cc8ace304bedd48c677804c6b77befcb8694e487a' 
  AND token = 'TXDC+NHVPR0QZvnjnlUrw09yyGJ7a0S/Din5CPnWdwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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