SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41dcfc5e225ceb690c480361965240399eb9208f7aaa42d21c7943a096db9640' 
  AND token = 'LXW88cbEalUK7GggU8dz/aHgDmRI2ZPzWsIe461H++U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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