SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5acb9b98c12abad8a0da23191e9c395615aaf1cd301b8249f28915e8519186c' 
  AND token = 'L/Jr2ODTYx2CeDIzksJgVRPzXEf3CrTHHYw576fL0dE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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