SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c236d494aba5b3dd5cf0f494d0728e5e32cdab508d1bc4c23aa643b9fbb64d97' 
  AND token = '+oowvwsgGeH2hOUnEwrB+t6Hqt3BqUnEKJsZVxERz5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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