SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5380beaf25d36a157033b320b35c3fbb9d80106944fe5d0ad55a0428b1bed87' 
  AND token = 'V22e9GS9v8CjhHSgp3syMyISj2vYgDtvDjW7gCYyFrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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