SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4b86cdeccce7db88eeb4bf48e22d799ce6c170127304befbc03d9f1a885da9d' 
  AND token = '0Jh8drsbqzALlLqdgJEkaVJLPRCmEFNVmyAlSF71OJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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