SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa5bd1c378effbdcb73bdb5ef3db7b3309d11eeadca3cda2fb6931f1ca4e1982' 
  AND token = '6eKNIyGH4FJB3ldEdaYCewx645nQJgc++dsJkDg+iHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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