SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8204b716f1db968280250f9f02085d3089a33cabdcaa96f42ecb130b0f693bd3' 
  AND token = 'SbB3J27ufgD33BstFRnU8VlgTWd9t8xDaRjklZGQCN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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