SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8e2203392cb93210b27a753411fec6140ffd482bbacef20948f0fbdbb5d59cc' 
  AND token = 'HxPM0H8gbK/OWmBMjhbSLzSDVsoqW8c6pNsR+ahtU2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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