SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e817d70496700dbea772c54f937185f7a7bef06bae84844141e5abbb52046b59' 
  AND token = '+IBMMcYtv7C14+jje4KBhRGogctdQmR/q2jvdJz3+dM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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