SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e09f1aca10c119d2dc82cdffaa4ea2d84a698d5baf2f4d0fdca4e257998fef45' 
  AND token = 'vi6JDAz3PIuZMfEhzzoYIEA+T5qbOSfhSbVcKM+qwnc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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