SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f031af1d9756d0130d44ea827e133cce801d7da61256ab121916530f0069f31' 
  AND token = 'RyCimlI1kRfWSZKbIvN4C/TUC5KXoMjBb65HN8ukkIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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